Supplement

Cocoa Extract

Cocoa extract is a concentrated source of cacao flavanols, plant compounds that help blood vessel walls make nitric oxide so the vessels relax and widen. Most people look at it for high blood pressure, where the evidence is strong and a Cochrane review found pressure came down. Beyond that the evidence is thinner, and one small study of 20 people found no clear difference in adiponectin.

Sources: PMID 22301923

Updated 30 September 2026
How we grade
56 studies cited

Best evidence: Grade B
Conditions studied: 26
Outcomes: 269
Graded outcomes: 011112

Evidence by condition

Strong
Moderate
Limited
Very limited

26 conditions

Obesity

Obesity: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	Blood Flow Moderate Increase	Improves (the measure goes up)	Moderate effect	2 studies	69 people
Studies that measured blood flow NOX2-mediated arterial dysfunction in smokers: acute effect of dark chocolateHeart · PMID 21807659 Long-term ingestion of high flavanol cocoa provides photoprotection against UV-induced erythema and improves skin condition in womenJ Nutr · PMID 16702322
	High-density lipoprotein (HDL)	Improves (the measure goes up)		13 studies	84 people
Studies that measured high-density lipoprotein (hdl) Effects of cocoa products/dark chocolate on serum lipids: a meta-analysisEur J Clin Nutr · PMID 21559039 Regular consumption of a flavanol-rich chocolate can improve oxidant stress in young soccer playersClin Dev Immunol · PMID 15712594 Effect of cocoa flavanols and exercise on cardiometabolic risk factors in overweight and obese subjectsInt J Obes · PMID 18504447 Short-term administration of dark chocolate is followed by a significant increase in insulin sensitivity and a decrease in blood pressure in healthy personsAm J Clin Nutr · PMID 15755830 Cocoa consumption for 2 wk enhances insulin-mediated vasodilatation without improving blood pressure or insulin resistance in essential hypertensionAm J Clin Nutr · PMID 19064532 Blood pressure is reduced and insulin sensitivity increased in glucose-intolerant, hypertensive subjects after 15 days of consuming high-polyphenol dark chocolateJ Nutr · PMID 18716168 Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adultsJ Am Coll Nutr · PMID 15190043 A double-blind, placebo-controlled, randomized trial of the effects of dark chocolate and cocoa on variables associated with neuropsychological functioning and cardiovascular health: clinical findings from a sample of healthy, cognitively intact older adultsAm J Clin Nutr · PMID 18400709 Dark chocolate effect on platelet activity, C-reactive protein and lipid profile: a pilot studySouth Med J · PMID 19005437 Effects of dark chocolate and cocoa consumption on endothelial function and arterial stiffness in overweight adultsBr J Nutr · PMID 24274771 and 3 more in the citations list
	Blood Pressure	Improves (the measure goes down)		10 studies	69 people
Studies that measured blood pressure Safety and efficacy of cocoa flavanol intake in healthy adults: a randomized, controlled, double-masked trialAm J Clin Nutr · PMID 26537937 Characterisation of hypertensive patients with improved endothelial function after dark chocolate consumptionInt J Hypertens · PMID 23533716 Blood pressure and endothelial function in healthy, pregnant women after acute and daily consumption of flavanol-rich chocolate: a pilot, randomized controlled trialNutr J · PMID 23565841 Effect of dark chocolate on nitric oxide serum levels and blood pressure in prehypertension subjectsActa Med Indones · PMID 22156352 Effect of cocoa on blood pressureCochrane Database Syst Rev · PMID 28439881 Dark chocolate or tomato extract for prehypertension: a randomised controlled trialBMC Complement Altern Med · PMID 19583878 Dark chocolate for children's blood pressure: randomised trialArch Dis Child · PMID 22685047 Effect of cocoa products on blood pressure: systematic review and meta-analysis.Am J Hypertens · PMID 19910929 Postprandial effects of dark chocolate on portal hypertension in patients with cirrhosis: results of a phase 2, double-blind, randomized controlled trialAm J Clin Nutr · PMID 22811444 The short-term effect of flavonoid-rich dark chocolate on retinal vessel diameter in glaucoma patients and age-matched controlsActa Ophthalmol · PMID 24628966
	Blood glucose	Improves (the measure goes down)		5 studies	35 people
Studies that measured blood glucose The effect of polyphenol-rich dark chocolate on fasting capillary whole blood glucose, total cholesterol, blood pressure and glucocorticoids in healthy overweight and obese subjectsBr J Nutr · PMID 19825207 Protective effects of flavanol-rich dark chocolate on endothelial function and wave reflection during acute hyperglycemiaHypertension · PMID 22851734 Dose-dependent increases in flow-mediated dilation following acute cocoa ingestion in healthy older adultsJ Appl Physiol · PMID 21903881 Cocoa reduces blood pressure and insulin resistance and improves endothelium-dependent vasodilation in hypertensivesHypertension · PMID 16027246 Consumption of high-polyphenol dark chocolate improves endothelial function in individuals with stage 1 hypertension and excess body weightInt J Hypertens · PMID 23209885
	Triglycerides	Improves (the measure goes down)		3 studies	69 people
Studies that measured triglycerides Prebiotic evaluation of cocoa-derived flavanols in healthy humans by using a randomized, controlled, double-blind, crossover intervention studyAm J Clin Nutr · PMID 21068351 Acute effect of oral flavonoid-rich dark chocolate intake on coronary circulation, as compared with non-flavonoid white chocolate, by transthoracic Doppler echocardiography in healthy adultsInt J Cardiol · PMID 18045712 Dark chocolate consumption improves leukocyte adhesion factors and vascular function in overweight menFASEB J · PMID 24302679
	C-Reactive Protein (CRP)	Improves (the measure goes down)		1 study	35 people
	Fat Oxidation	Improves (the measure goes up)		1 study	49 people
	Body Fat	Improves (the measure goes down)			20 people
	Cell Adhesion Factors	Improves (the measure goes down)			20 people
	Fibrinogen	Improves (the measure goes up)			15 people
	Glycemic Control	Improves (the measure goes up)			84 people
	Heart Rate	Improves (the measure goes down)			49 people
	IL-1Ra	Improves (the measure goes down)			15 people
	Insulin	Changes; see studies			35 people
	Interleukin 1-alpha	Improves (the measure goes up)			15 people
	Interleukin 1-beta	Improves (the measure goes down)			15 people
	Interleukin 6	Improves (the measure goes down)			35 people
	Kidney Function	Improves (the measure goes up)			15 people
	LDL Oxidation	Improves (the measure goes down)			20 people
	Liver Enzymes	Changes; see studies			15 people
	Low-density lipoprotein (LDL)	Improves (the measure goes down)			84 people
	Muscle Mass	Improves (the measure goes up)			20 people
	TNF-Alpha	Improves (the measure goes down)			35 people
	Total cholesterol	Improves (the measure goes down)			84 people
	Weight	Improves (the measure goes down)			84 people

Glaucoma

Glaucoma: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	Blood Pressure Small Improvement	Improves (the measure goes down)	Small effect	10 studies	60 people
Studies that measured blood pressure Safety and efficacy of cocoa flavanol intake in healthy adults: a randomized, controlled, double-masked trialAm J Clin Nutr · PMID 26537937 Characterisation of hypertensive patients with improved endothelial function after dark chocolate consumptionInt J Hypertens · PMID 23533716 Blood pressure and endothelial function in healthy, pregnant women after acute and daily consumption of flavanol-rich chocolate: a pilot, randomized controlled trialNutr J · PMID 23565841 Effect of dark chocolate on nitric oxide serum levels and blood pressure in prehypertension subjectsActa Med Indones · PMID 22156352 Effect of cocoa on blood pressureCochrane Database Syst Rev · PMID 28439881 Dark chocolate or tomato extract for prehypertension: a randomised controlled trialBMC Complement Altern Med · PMID 19583878 Dark chocolate for children's blood pressure: randomised trialArch Dis Child · PMID 22685047 Effect of cocoa products on blood pressure: systematic review and meta-analysis.Am J Hypertens · PMID 19910929 Postprandial effects of dark chocolate on portal hypertension in patients with cirrhosis: results of a phase 2, double-blind, randomized controlled trialAm J Clin Nutr · PMID 22811444 The short-term effect of flavonoid-rich dark chocolate on retinal vessel diameter in glaucoma patients and age-matched controlsActa Ophthalmol · PMID 24628966
	Intraocular Pressure	Improves (the measure goes up)			60 people

Cirrhosis

Blood Pressure: improves
Heart Rate: improves
Hepatic Venous Pressure Gradient: improves

Cirrhosis: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	Blood Pressure Small Improvement	Improves (the measure goes down)	Small effect	10 studies	22 people
Studies that measured blood pressure Safety and efficacy of cocoa flavanol intake in healthy adults: a randomized, controlled, double-masked trialAm J Clin Nutr · PMID 26537937 Characterisation of hypertensive patients with improved endothelial function after dark chocolate consumptionInt J Hypertens · PMID 23533716 Blood pressure and endothelial function in healthy, pregnant women after acute and daily consumption of flavanol-rich chocolate: a pilot, randomized controlled trialNutr J · PMID 23565841 Effect of dark chocolate on nitric oxide serum levels and blood pressure in prehypertension subjectsActa Med Indones · PMID 22156352 Effect of cocoa on blood pressureCochrane Database Syst Rev · PMID 28439881 Dark chocolate or tomato extract for prehypertension: a randomised controlled trialBMC Complement Altern Med · PMID 19583878 Dark chocolate for children's blood pressure: randomised trialArch Dis Child · PMID 22685047 Effect of cocoa products on blood pressure: systematic review and meta-analysis.Am J Hypertens · PMID 19910929 Postprandial effects of dark chocolate on portal hypertension in patients with cirrhosis: results of a phase 2, double-blind, randomized controlled trialAm J Clin Nutr · PMID 22811444 The short-term effect of flavonoid-rich dark chocolate on retinal vessel diameter in glaucoma patients and age-matched controlsActa Ophthalmol · PMID 24628966
	Heart Rate	Improves (the measure goes down)			22 people
	Hepatic Venous Pressure Gradient	Improves (the measure goes up)			22 people
	Portal Hypertension Signs	Improves (the measure goes down)			22 people

Eye Health

Blood Pressure: improves
Intraocular Pressure: improves

Eye Health: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	Blood Pressure Small Improvement	Improves (the measure goes down)	Small effect	10 studies	60 people
Studies that measured blood pressure Safety and efficacy of cocoa flavanol intake in healthy adults: a randomized, controlled, double-masked trialAm J Clin Nutr · PMID 26537937 Characterisation of hypertensive patients with improved endothelial function after dark chocolate consumptionInt J Hypertens · PMID 23533716 Blood pressure and endothelial function in healthy, pregnant women after acute and daily consumption of flavanol-rich chocolate: a pilot, randomized controlled trialNutr J · PMID 23565841 Effect of dark chocolate on nitric oxide serum levels and blood pressure in prehypertension subjectsActa Med Indones · PMID 22156352 Effect of cocoa on blood pressureCochrane Database Syst Rev · PMID 28439881 Dark chocolate or tomato extract for prehypertension: a randomised controlled trialBMC Complement Altern Med · PMID 19583878 Dark chocolate for children's blood pressure: randomised trialArch Dis Child · PMID 22685047 Effect of cocoa products on blood pressure: systematic review and meta-analysis.Am J Hypertens · PMID 19910929 Postprandial effects of dark chocolate on portal hypertension in patients with cirrhosis: results of a phase 2, double-blind, randomized controlled trialAm J Clin Nutr · PMID 22811444 The short-term effect of flavonoid-rich dark chocolate on retinal vessel diameter in glaucoma patients and age-matched controlsActa Ophthalmol · PMID 24628966
	Intraocular Pressure	Improves (the measure goes up)			60 people

General Cardiovascular Health

Adrenaline: worsens
Adiponectin
High-density lipoprotein (HDL): improves

General Cardiovascular Health: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	Adrenaline Small Decrease	Worsens (the measure goes down)	Small effect	2 studies	31 people
Studies that measured adrenaline Dark chocolate intake buffers stress reactivity in humansJ Am Coll Cardiol · PMID 24681134 Effects of dark chocolate consumption on the prothrombotic response to acute psychosocial stress in healthy menThromb Haemost · PMID 25208561
	Adiponectin No effect		NoneNo effect		20 people
	High-density lipoprotein (HDL)	Improves (the measure goes up)		13 studies	2,218 people
Studies that measured high-density lipoprotein (hdl) Effects of cocoa products/dark chocolate on serum lipids: a meta-analysisEur J Clin Nutr · PMID 21559039 Regular consumption of a flavanol-rich chocolate can improve oxidant stress in young soccer playersClin Dev Immunol · PMID 15712594 Effect of cocoa flavanols and exercise on cardiometabolic risk factors in overweight and obese subjectsInt J Obes · PMID 18504447 Short-term administration of dark chocolate is followed by a significant increase in insulin sensitivity and a decrease in blood pressure in healthy personsAm J Clin Nutr · PMID 15755830 Cocoa consumption for 2 wk enhances insulin-mediated vasodilatation without improving blood pressure or insulin resistance in essential hypertensionAm J Clin Nutr · PMID 19064532 Blood pressure is reduced and insulin sensitivity increased in glucose-intolerant, hypertensive subjects after 15 days of consuming high-polyphenol dark chocolateJ Nutr · PMID 18716168 Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adultsJ Am Coll Nutr · PMID 15190043 A double-blind, placebo-controlled, randomized trial of the effects of dark chocolate and cocoa on variables associated with neuropsychological functioning and cardiovascular health: clinical findings from a sample of healthy, cognitively intact older adultsAm J Clin Nutr · PMID 18400709 Dark chocolate effect on platelet activity, C-reactive protein and lipid profile: a pilot studySouth Med J · PMID 19005437 Effects of dark chocolate and cocoa consumption on endothelial function and arterial stiffness in overweight adultsBr J Nutr · PMID 24274771 and 3 more in the citations list
	Blood Pressure	Improves (the measure goes down)		10 studies	2,499 people
Studies that measured blood pressure Safety and efficacy of cocoa flavanol intake in healthy adults: a randomized, controlled, double-masked trialAm J Clin Nutr · PMID 26537937 Characterisation of hypertensive patients with improved endothelial function after dark chocolate consumptionInt J Hypertens · PMID 23533716 Blood pressure and endothelial function in healthy, pregnant women after acute and daily consumption of flavanol-rich chocolate: a pilot, randomized controlled trialNutr J · PMID 23565841 Effect of dark chocolate on nitric oxide serum levels and blood pressure in prehypertension subjectsActa Med Indones · PMID 22156352 Effect of cocoa on blood pressureCochrane Database Syst Rev · PMID 28439881 Dark chocolate or tomato extract for prehypertension: a randomised controlled trialBMC Complement Altern Med · PMID 19583878 Dark chocolate for children's blood pressure: randomised trialArch Dis Child · PMID 22685047 Effect of cocoa products on blood pressure: systematic review and meta-analysis.Am J Hypertens · PMID 19910929 Postprandial effects of dark chocolate on portal hypertension in patients with cirrhosis: results of a phase 2, double-blind, randomized controlled trialAm J Clin Nutr · PMID 22811444 The short-term effect of flavonoid-rich dark chocolate on retinal vessel diameter in glaucoma patients and age-matched controlsActa Ophthalmol · PMID 24628966
	Blood glucose	Improves (the measure goes down)		5 studies	2,070 people
Studies that measured blood glucose The effect of polyphenol-rich dark chocolate on fasting capillary whole blood glucose, total cholesterol, blood pressure and glucocorticoids in healthy overweight and obese subjectsBr J Nutr · PMID 19825207 Protective effects of flavanol-rich dark chocolate on endothelial function and wave reflection during acute hyperglycemiaHypertension · PMID 22851734 Dose-dependent increases in flow-mediated dilation following acute cocoa ingestion in healthy older adultsJ Appl Physiol · PMID 21903881 Cocoa reduces blood pressure and insulin resistance and improves endothelium-dependent vasodilation in hypertensivesHypertension · PMID 16027246 Consumption of high-polyphenol dark chocolate improves endothelial function in individuals with stage 1 hypertension and excess body weightInt J Hypertens · PMID 23209885
	Triglycerides	Improves (the measure goes down)		3 studies	2,229 people
	Blood Flow	Improves (the measure goes up)		2 studies	307 people
	Oxidative Stress Biomarkers	Improves (the measure goes down)		2 studies	145 people
	Platelet Aggregation	Changes; see studies		2 studies	234 people
	Arterial Stiffness	Improves (the measure goes down)		1 study	47 people
	C-Reactive Protein (CRP)	Improves (the measure goes down)		1 study	118 people
	HbA1c	Improves (the measure goes down)		1 study	1,986 people
	Adrenocorticotropic Hormone	Improves (the measure goes up)			31 people
	Aerobic Exercise Metrics	Improves (the measure goes up)			28 people
	Body Mass Index (BMI)	Improves (the measure goes down)			1,986 people
	Cell Adhesion Factors	Improves (the measure goes down)			20 people
	Cognition	Improves (the measure goes up)			90 people
	Cortisol	Improves (the measure goes down)			31 people
	Food Intake	Changes; see studies			30 people
	Glycemic Control	Improves (the measure goes up)			77 people
	Heart Rate	Improves (the measure goes down)			167 people
	Insulin	Changes; see studies			77 people
	LDL Oxidation	Improves (the measure goes down)			83 people
	Leptin	Improves (the measure goes up)			20 people
	Low-density lipoprotein (LDL)	Improves (the measure goes down)			2,218 people
	Memory	Improves (the measure goes up)			90 people
	Nitric Oxide	Improves (the measure goes up)			110 people
	Noradrenaline	Improves (the measure goes up)			54 people
	Plasma Vitamin E	Improves (the measure goes up)			28 people
	TNF-Alpha	Improves (the measure goes down)			20 people
	Total cholesterol	Improves (the measure goes down)			2,190 people
	vLDL-C	Improves (the measure goes down)			90 people
	Waist circumference	Improves (the measure goes down)			1,986 people
	Weight	Improves (the measure goes down)			2,155 people

Skin Health

Blood Flow: improves
Skin Dryness: improves
Photoprotection: improves

Skin Health: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	Blood Flow Moderate Increase	Improves (the measure goes up)	Moderate effect	2 studies	24 people
Studies that measured blood flow NOX2-mediated arterial dysfunction in smokers: acute effect of dark chocolateHeart · PMID 21807659 Long-term ingestion of high flavanol cocoa provides photoprotection against UV-induced erythema and improves skin condition in womenJ Nutr · PMID 16702322
	Skin Dryness	Improves (the measure goes up)		2 studies	141 people
Studies that measured skin dryness Chocolate flavanols and skin photoprotection: a parallel, double-blind, randomized clinical trialNutr J · PMID 24970388 Cocoa Flavanol Supplementation Influences Skin Conditions of Photo-Aged Women: A 24-Week Double-Blind, Randomized, Controlled TrialJ Nutr · PMID 26581682
	Photoprotection	Improves (the measure goes up)			141 people
	Skin Elasticity	Improves (the measure goes up)			117 people

Type 2 Diabetes

Blood Flow: improves
High-density lipoprotein (HDL): improves
Blood Pressure: improves

Type 2 Diabetes: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	Blood Flow Moderate Increase	Improves (the measure goes up)	Moderate effect	2 studies	41 people
Studies that measured blood flow NOX2-mediated arterial dysfunction in smokers: acute effect of dark chocolateHeart · PMID 21807659 Long-term ingestion of high flavanol cocoa provides photoprotection against UV-induced erythema and improves skin condition in womenJ Nutr · PMID 16702322
	High-density lipoprotein (HDL)	Improves (the measure goes up)		13 studies	41 people
Studies that measured high-density lipoprotein (hdl) Effects of cocoa products/dark chocolate on serum lipids: a meta-analysisEur J Clin Nutr · PMID 21559039 Regular consumption of a flavanol-rich chocolate can improve oxidant stress in young soccer playersClin Dev Immunol · PMID 15712594 Effect of cocoa flavanols and exercise on cardiometabolic risk factors in overweight and obese subjectsInt J Obes · PMID 18504447 Short-term administration of dark chocolate is followed by a significant increase in insulin sensitivity and a decrease in blood pressure in healthy personsAm J Clin Nutr · PMID 15755830 Cocoa consumption for 2 wk enhances insulin-mediated vasodilatation without improving blood pressure or insulin resistance in essential hypertensionAm J Clin Nutr · PMID 19064532 Blood pressure is reduced and insulin sensitivity increased in glucose-intolerant, hypertensive subjects after 15 days of consuming high-polyphenol dark chocolateJ Nutr · PMID 18716168 Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adultsJ Am Coll Nutr · PMID 15190043 A double-blind, placebo-controlled, randomized trial of the effects of dark chocolate and cocoa on variables associated with neuropsychological functioning and cardiovascular health: clinical findings from a sample of healthy, cognitively intact older adultsAm J Clin Nutr · PMID 18400709 Dark chocolate effect on platelet activity, C-reactive protein and lipid profile: a pilot studySouth Med J · PMID 19005437 Effects of dark chocolate and cocoa consumption on endothelial function and arterial stiffness in overweight adultsBr J Nutr · PMID 24274771 and 3 more in the citations list
	Blood Pressure	Improves (the measure goes down)		10 studies	41 people
Studies that measured blood pressure Safety and efficacy of cocoa flavanol intake in healthy adults: a randomized, controlled, double-masked trialAm J Clin Nutr · PMID 26537937 Characterisation of hypertensive patients with improved endothelial function after dark chocolate consumptionInt J Hypertens · PMID 23533716 Blood pressure and endothelial function in healthy, pregnant women after acute and daily consumption of flavanol-rich chocolate: a pilot, randomized controlled trialNutr J · PMID 23565841 Effect of dark chocolate on nitric oxide serum levels and blood pressure in prehypertension subjectsActa Med Indones · PMID 22156352 Effect of cocoa on blood pressureCochrane Database Syst Rev · PMID 28439881 Dark chocolate or tomato extract for prehypertension: a randomised controlled trialBMC Complement Altern Med · PMID 19583878 Dark chocolate for children's blood pressure: randomised trialArch Dis Child · PMID 22685047 Effect of cocoa products on blood pressure: systematic review and meta-analysis.Am J Hypertens · PMID 19910929 Postprandial effects of dark chocolate on portal hypertension in patients with cirrhosis: results of a phase 2, double-blind, randomized controlled trialAm J Clin Nutr · PMID 22811444 The short-term effect of flavonoid-rich dark chocolate on retinal vessel diameter in glaucoma patients and age-matched controlsActa Ophthalmol · PMID 24628966
	Blood glucose	Improves (the measure goes down)		5 studies	41 people
Studies that measured blood glucose The effect of polyphenol-rich dark chocolate on fasting capillary whole blood glucose, total cholesterol, blood pressure and glucocorticoids in healthy overweight and obese subjectsBr J Nutr · PMID 19825207 Protective effects of flavanol-rich dark chocolate on endothelial function and wave reflection during acute hyperglycemiaHypertension · PMID 22851734 Dose-dependent increases in flow-mediated dilation following acute cocoa ingestion in healthy older adultsJ Appl Physiol · PMID 21903881 Cocoa reduces blood pressure and insulin resistance and improves endothelium-dependent vasodilation in hypertensivesHypertension · PMID 16027246 Consumption of high-polyphenol dark chocolate improves endothelial function in individuals with stage 1 hypertension and excess body weightInt J Hypertens · PMID 23209885
	Triglycerides	Improves (the measure goes down)		3 studies	41 people
Studies that measured triglycerides Prebiotic evaluation of cocoa-derived flavanols in healthy humans by using a randomized, controlled, double-blind, crossover intervention studyAm J Clin Nutr · PMID 21068351 Acute effect of oral flavonoid-rich dark chocolate intake on coronary circulation, as compared with non-flavonoid white chocolate, by transthoracic Doppler echocardiography in healthy adultsInt J Cardiol · PMID 18045712 Dark chocolate consumption improves leukocyte adhesion factors and vascular function in overweight menFASEB J · PMID 24302679
	C-Reactive Protein (CRP)	Improves (the measure goes down)		1 study	41 people
	HbA1c	Improves (the measure goes down)		1 study	41 people
	Mitochondrial Protection	Improves (the measure goes up)		1 study	5 people
	Heart Rate	Improves (the measure goes down)			41 people
	Kidney Function	Improves (the measure goes up)			41 people
	Low-density lipoprotein (LDL)	Improves (the measure goes down)			41 people
	Total cholesterol	Improves (the measure goes down)			41 people
	Urea	Improves (the measure goes up)			41 people
	Weight	Improves (the measure goes down)			41 people

Peripheral Arterial Disease

Blood Flow: improves
Oxidative Stress Biomarkers: improves
Peripheral Vascular Disease Symptoms: improves

Peripheral Arterial Disease: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	Blood Flow Moderate Increase	Improves (the measure goes up)	Moderate effect	2 studies	43 people
Studies that measured blood flow NOX2-mediated arterial dysfunction in smokers: acute effect of dark chocolateHeart · PMID 21807659 Long-term ingestion of high flavanol cocoa provides photoprotection against UV-induced erythema and improves skin condition in womenJ Nutr · PMID 16702322
	Oxidative Stress Biomarkers	Improves (the measure goes down)		2 studies	22 people
Studies that measured oxidative stress biomarkers Dark chocolate inhibits platelet isoprostanes via NOX2 down-regulation in smokersJ Thromb Haemost · PMID 22066819 Influence of cocoa flavanols and procyanidins on free radical-induced human erythrocyte hemolysisClin Dev Immunol · PMID 15712596
	Peripheral Vascular Disease Symptoms	Improves (the measure goes down)		2 studies	43 people
Studies that measured peripheral vascular disease symptoms Dark chocolate and vascular function in patients with peripheral artery disease: a randomized, controlled cross-over trialClin Hemorheol Microcirc · PMID 24531123 Dark chocolate acutely improves walking autonomy in patients with peripheral artery diseaseJ Am Heart Assoc · PMID 24990275
	Nitric Oxide	Improves (the measure goes up)			43 people

Weight Loss & Maintenance

Blood Flow: improves
High-density lipoprotein (HDL): improves
Blood Pressure: improves

Weight Loss & Maintenance: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	Blood Flow Moderate Increase	Improves (the measure goes up)	Moderate effect	2 studies	49 people
Studies that measured blood flow NOX2-mediated arterial dysfunction in smokers: acute effect of dark chocolateHeart · PMID 21807659 Long-term ingestion of high flavanol cocoa provides photoprotection against UV-induced erythema and improves skin condition in womenJ Nutr · PMID 16702322
	High-density lipoprotein (HDL)	Improves (the measure goes up)		13 studies	49 people
Studies that measured high-density lipoprotein (hdl) Effects of cocoa products/dark chocolate on serum lipids: a meta-analysisEur J Clin Nutr · PMID 21559039 Regular consumption of a flavanol-rich chocolate can improve oxidant stress in young soccer playersClin Dev Immunol · PMID 15712594 Effect of cocoa flavanols and exercise on cardiometabolic risk factors in overweight and obese subjectsInt J Obes · PMID 18504447 Short-term administration of dark chocolate is followed by a significant increase in insulin sensitivity and a decrease in blood pressure in healthy personsAm J Clin Nutr · PMID 15755830 Cocoa consumption for 2 wk enhances insulin-mediated vasodilatation without improving blood pressure or insulin resistance in essential hypertensionAm J Clin Nutr · PMID 19064532 Blood pressure is reduced and insulin sensitivity increased in glucose-intolerant, hypertensive subjects after 15 days of consuming high-polyphenol dark chocolateJ Nutr · PMID 18716168 Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adultsJ Am Coll Nutr · PMID 15190043 A double-blind, placebo-controlled, randomized trial of the effects of dark chocolate and cocoa on variables associated with neuropsychological functioning and cardiovascular health: clinical findings from a sample of healthy, cognitively intact older adultsAm J Clin Nutr · PMID 18400709 Dark chocolate effect on platelet activity, C-reactive protein and lipid profile: a pilot studySouth Med J · PMID 19005437 Effects of dark chocolate and cocoa consumption on endothelial function and arterial stiffness in overweight adultsBr J Nutr · PMID 24274771 and 3 more in the citations list
	Blood Pressure	Improves (the measure goes down)		10 studies	85 people
Studies that measured blood pressure Safety and efficacy of cocoa flavanol intake in healthy adults: a randomized, controlled, double-masked trialAm J Clin Nutr · PMID 26537937 Characterisation of hypertensive patients with improved endothelial function after dark chocolate consumptionInt J Hypertens · PMID 23533716 Blood pressure and endothelial function in healthy, pregnant women after acute and daily consumption of flavanol-rich chocolate: a pilot, randomized controlled trialNutr J · PMID 23565841 Effect of dark chocolate on nitric oxide serum levels and blood pressure in prehypertension subjectsActa Med Indones · PMID 22156352 Effect of cocoa on blood pressureCochrane Database Syst Rev · PMID 28439881 Dark chocolate or tomato extract for prehypertension: a randomised controlled trialBMC Complement Altern Med · PMID 19583878 Dark chocolate for children's blood pressure: randomised trialArch Dis Child · PMID 22685047 Effect of cocoa products on blood pressure: systematic review and meta-analysis.Am J Hypertens · PMID 19910929 Postprandial effects of dark chocolate on portal hypertension in patients with cirrhosis: results of a phase 2, double-blind, randomized controlled trialAm J Clin Nutr · PMID 22811444 The short-term effect of flavonoid-rich dark chocolate on retinal vessel diameter in glaucoma patients and age-matched controlsActa Ophthalmol · PMID 24628966
	Triglycerides	Improves (the measure goes down)		3 studies	49 people
Studies that measured triglycerides Prebiotic evaluation of cocoa-derived flavanols in healthy humans by using a randomized, controlled, double-blind, crossover intervention studyAm J Clin Nutr · PMID 21068351 Acute effect of oral flavonoid-rich dark chocolate intake on coronary circulation, as compared with non-flavonoid white chocolate, by transthoracic Doppler echocardiography in healthy adultsInt J Cardiol · PMID 18045712 Dark chocolate consumption improves leukocyte adhesion factors and vascular function in overweight menFASEB J · PMID 24302679
	Fat Oxidation	Improves (the measure goes up)		1 study	49 people
Studies that measured fat oxidation Regular dark chocolate consumption's reduction of oxidative stress and increase of free-fatty-acid mobilization in response to prolonged cyclingInt J Sport Nutr Exerc Metab · PMID 21558573
	Body Fat	Improves (the measure goes down)			36 people
	Glycemic Control	Improves (the measure goes up)			49 people
	Low-density lipoprotein (LDL)	Improves (the measure goes down)			49 people
	Subjective Well-Being	Improves (the measure goes up)			36 people
	Total cholesterol	Improves (the measure goes down)			49 people
	Weight	Improves (the measure goes down)			85 people

Stress

Adrenaline: worsens
Blood Viscosity: improves
Noradrenaline: improves

Stress: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	Adrenaline Small Decrease	Worsens (the measure goes down)	Small effect	2 studies	65 people
Studies that measured adrenaline Dark chocolate intake buffers stress reactivity in humansJ Am Coll Cardiol · PMID 24681134 Effects of dark chocolate consumption on the prothrombotic response to acute psychosocial stress in healthy menThromb Haemost · PMID 25208561
	Blood Viscosity	Improves (the measure goes up)			65 people
	Noradrenaline	Improves (the measure goes up)			65 people

Cardiovascular Disease

All-Cause Mortality: improves
High-density lipoprotein (HDL): improves
Blood Pressure: improves

Cardiovascular Disease: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	All-Cause Mortality Small Improvement	Improves (the measure goes down)	Small effect	1 study	908,390 people
Studies that measured all-cause mortality Relationship between chocolate consumption and overall and cause-specific mortality, systematic review and updated meta-analysis.Eur J Epidemiol · PMID 35460393
	High-density lipoprotein (HDL)	Improves (the measure goes up)		13 studies	986 people
Studies that measured high-density lipoprotein (hdl) Effects of cocoa products/dark chocolate on serum lipids: a meta-analysisEur J Clin Nutr · PMID 21559039 Regular consumption of a flavanol-rich chocolate can improve oxidant stress in young soccer playersClin Dev Immunol · PMID 15712594 Effect of cocoa flavanols and exercise on cardiometabolic risk factors in overweight and obese subjectsInt J Obes · PMID 18504447 Short-term administration of dark chocolate is followed by a significant increase in insulin sensitivity and a decrease in blood pressure in healthy personsAm J Clin Nutr · PMID 15755830 Cocoa consumption for 2 wk enhances insulin-mediated vasodilatation without improving blood pressure or insulin resistance in essential hypertensionAm J Clin Nutr · PMID 19064532 Blood pressure is reduced and insulin sensitivity increased in glucose-intolerant, hypertensive subjects after 15 days of consuming high-polyphenol dark chocolateJ Nutr · PMID 18716168 Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adultsJ Am Coll Nutr · PMID 15190043 A double-blind, placebo-controlled, randomized trial of the effects of dark chocolate and cocoa on variables associated with neuropsychological functioning and cardiovascular health: clinical findings from a sample of healthy, cognitively intact older adultsAm J Clin Nutr · PMID 18400709 Dark chocolate effect on platelet activity, C-reactive protein and lipid profile: a pilot studySouth Med J · PMID 19005437 Effects of dark chocolate and cocoa consumption on endothelial function and arterial stiffness in overweight adultsBr J Nutr · PMID 24274771 and 3 more in the citations list
	Blood Pressure	Improves (the measure goes down)		10 studies	918 people
Studies that measured blood pressure Safety and efficacy of cocoa flavanol intake in healthy adults: a randomized, controlled, double-masked trialAm J Clin Nutr · PMID 26537937 Characterisation of hypertensive patients with improved endothelial function after dark chocolate consumptionInt J Hypertens · PMID 23533716 Blood pressure and endothelial function in healthy, pregnant women after acute and daily consumption of flavanol-rich chocolate: a pilot, randomized controlled trialNutr J · PMID 23565841 Effect of dark chocolate on nitric oxide serum levels and blood pressure in prehypertension subjectsActa Med Indones · PMID 22156352 Effect of cocoa on blood pressureCochrane Database Syst Rev · PMID 28439881 Dark chocolate or tomato extract for prehypertension: a randomised controlled trialBMC Complement Altern Med · PMID 19583878 Dark chocolate for children's blood pressure: randomised trialArch Dis Child · PMID 22685047 Effect of cocoa products on blood pressure: systematic review and meta-analysis.Am J Hypertens · PMID 19910929 Postprandial effects of dark chocolate on portal hypertension in patients with cirrhosis: results of a phase 2, double-blind, randomized controlled trialAm J Clin Nutr · PMID 22811444 The short-term effect of flavonoid-rich dark chocolate on retinal vessel diameter in glaucoma patients and age-matched controlsActa Ophthalmol · PMID 24628966
	Blood glucose	Improves (the measure goes down)		5 studies	459 people
Studies that measured blood glucose The effect of polyphenol-rich dark chocolate on fasting capillary whole blood glucose, total cholesterol, blood pressure and glucocorticoids in healthy overweight and obese subjectsBr J Nutr · PMID 19825207 Protective effects of flavanol-rich dark chocolate on endothelial function and wave reflection during acute hyperglycemiaHypertension · PMID 22851734 Dose-dependent increases in flow-mediated dilation following acute cocoa ingestion in healthy older adultsJ Appl Physiol · PMID 21903881 Cocoa reduces blood pressure and insulin resistance and improves endothelium-dependent vasodilation in hypertensivesHypertension · PMID 16027246 Consumption of high-polyphenol dark chocolate improves endothelial function in individuals with stage 1 hypertension and excess body weightInt J Hypertens · PMID 23209885
	Triglycerides	Improves (the measure goes down)		3 studies	3,303 people
Studies that measured triglycerides Prebiotic evaluation of cocoa-derived flavanols in healthy humans by using a randomized, controlled, double-blind, crossover intervention studyAm J Clin Nutr · PMID 21068351 Acute effect of oral flavonoid-rich dark chocolate intake on coronary circulation, as compared with non-flavonoid white chocolate, by transthoracic Doppler echocardiography in healthy adultsInt J Cardiol · PMID 18045712 Dark chocolate consumption improves leukocyte adhesion factors and vascular function in overweight menFASEB J · PMID 24302679
	Blood Flow	Improves (the measure goes up)		2 studies	20 people
	C-Reactive Protein (CRP)	Improves (the measure goes down)		1 study	1,317 people
	HbA1c	Improves (the measure goes down)		1 study	1,986 people
	Heart Failure Risk	Changes; see studies		1 study	114,009 people
	Risk Of Cardiovascular Disease	Improves (the measure goes down)		1 study	114,009 people
	Body Mass Index (BMI)	Improves (the measure goes down)			1,986 people
	Cardiovascular Disease Mortality	Improves (the measure goes down)			908,390 people
	Cell Adhesion Factors	Improves (the measure goes down)			20 people
	Glycemic Control	Improves (the measure goes up)			20 people
	Insulin	Changes; see studies			153 people
	Insulin Resistance	Improves (the measure goes down)			181 people
	Low-density lipoprotein (LDL)	Improves (the measure goes down)			986 people
	Stroke Risk	Changes; see studies			114,009 people
	Total cholesterol	Improves (the measure goes down)			3,303 people
	Waist circumference	Improves (the measure goes down)			1,986 people
	Weight	Improves (the measure goes down)			1,986 people

Overweight

Arterial Stiffness: improves
High-density lipoprotein (HDL): improves
Blood Pressure: improves

Overweight: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People
	Arterial Stiffness Small Improvement	Improves (the measure goes down)	Small effect	1 study	30 people
Studies that measured arterial stiffness Effect of dark chocolate on arterial function in healthy individualsAm J Hypertens · PMID 15925737
	High-density lipoprotein (HDL)	Improves (the measure goes up)		13 studies	79 people
Studies that measured high-density lipoprotein (hdl) Effects of cocoa products/dark chocolate on serum lipids: a meta-analysisEur J Clin Nutr · PMID 21559039 Regular consumption of a flavanol-rich chocolate can improve oxidant stress in young soccer playersClin Dev Immunol · PMID 15712594 Effect of cocoa flavanols and exercise on cardiometabolic risk factors in overweight and obese subjectsInt J Obes · PMID 18504447 Short-term administration of dark chocolate is followed by a significant increase in insulin sensitivity and a decrease in blood pressure in healthy personsAm J Clin Nutr · PMID 15755830 Cocoa consumption for 2 wk enhances insulin-mediated vasodilatation without improving blood pressure or insulin resistance in essential hypertensionAm J Clin Nutr · PMID 19064532 Blood pressure is reduced and insulin sensitivity increased in glucose-intolerant, hypertensive subjects after 15 days of consuming high-polyphenol dark chocolateJ Nutr · PMID 18716168 Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adultsJ Am Coll Nutr · PMID 15190043 A double-blind, placebo-controlled, randomized trial of the effects of dark chocolate and cocoa on variables associated with neuropsychological functioning and cardiovascular health: clinical findings from a sample of healthy, cognitively intact older adultsAm J Clin Nutr · PMID 18400709 Dark chocolate effect on platelet activity, C-reactive protein and lipid profile: a pilot studySouth Med J · PMID 19005437 Effects of dark chocolate and cocoa consumption on endothelial function and arterial stiffness in overweight adultsBr J Nutr · PMID 24274771 and 3 more in the citations list
	Blood Pressure	Improves (the measure goes down)		10 studies	109 people
Studies that measured blood pressure Safety and efficacy of cocoa flavanol intake in healthy adults: a randomized, controlled, double-masked trialAm J Clin Nutr · PMID 26537937 Characterisation of hypertensive patients with improved endothelial function after dark chocolate consumptionInt J Hypertens · PMID 23533716 Blood pressure and endothelial function in healthy, pregnant women after acute and daily consumption of flavanol-rich chocolate: a pilot, randomized controlled trialNutr J · PMID 23565841 Effect of dark chocolate on nitric oxide serum levels and blood pressure in prehypertension subjectsActa Med Indones · PMID 22156352 Effect of cocoa on blood pressureCochrane Database Syst Rev · PMID 28439881 Dark chocolate or tomato extract for prehypertension: a randomised controlled trialBMC Complement Altern Med · PMID 19583878 Dark chocolate for children's blood pressure: randomised trialArch Dis Child · PMID 22685047 Effect of cocoa products on blood pressure: systematic review and meta-analysis.Am J Hypertens · PMID 19910929 Postprandial effects of dark chocolate on portal hypertension in patients with cirrhosis: results of a phase 2, double-blind, randomized controlled trialAm J Clin Nutr · PMID 22811444 The short-term effect of flavonoid-rich dark chocolate on retinal vessel diameter in glaucoma patients and age-matched controlsActa Ophthalmol · PMID 24628966
	Blood glucose	Improves (the measure goes down)		5 studies	70 people
Studies that measured blood glucose The effect of polyphenol-rich dark chocolate on fasting capillary whole blood glucose, total cholesterol, blood pressure and glucocorticoids in healthy overweight and obese subjectsBr J Nutr · PMID 19825207 Protective effects of flavanol-rich dark chocolate on endothelial function and wave reflection during acute hyperglycemiaHypertension · PMID 22851734 Dose-dependent increases in flow-mediated dilation following acute cocoa ingestion in healthy older adultsJ Appl Physiol · PMID 21903881 Cocoa reduces blood pressure and insulin resistance and improves endothelium-dependent vasodilation in hypertensivesHypertension · PMID 16027246 Consumption of high-polyphenol dark chocolate improves endothelial function in individuals with stage 1 hypertension and excess body weightInt J Hypertens · PMID 23209885
	Triglycerides	Improves (the measure goes down)		3 studies	149 people
Studies that measured triglycerides Prebiotic evaluation of cocoa-derived flavanols in healthy humans by using a randomized, controlled, double-blind, crossover intervention studyAm J Clin Nutr · PMID 21068351 Acute effect of oral flavonoid-rich dark chocolate intake on coronary circulation, as compared with non-flavonoid white chocolate, by transthoracic Doppler echocardiography in healthy adultsInt J Cardiol · PMID 18045712 Dark chocolate consumption improves leukocyte adhesion factors and vascular function in overweight menFASEB J · PMID 24302679
	Blood Flow	Improves (the measure goes up)		2 studies	149 people
	Fat Oxidation	Improves (the measure goes up)		1 study	49 people
	Cell Adhesion Factors	Improves (the measure goes down)			70 people
	Glycemic Control	Improves (the measure goes up)			79 people
	Heart Rate	Improves (the measure goes down)			49 people
	Insulin	Changes; see studies			100 people
	Interleukin 1-beta	Improves (the measure goes down)			70 people
	Low-density lipoprotein (LDL)	Improves (the measure goes down)			79 people
	Total cholesterol	Improves (the measure goes down)			79 people
	Weight	Improves (the measure goes down)			49 people

Metabolic Syndrome

High-density lipoprotein (HDL)
Triglycerides: improves
Oxidative Stress Biomarkers: improves

Metabolic Syndrome: outcomes studied for Cocoa Extract
Outcome	Effect	Size	Studies	People
High-density lipoprotein (HDL) No effect		NoneNo effect	13 studies	23 people
Triglycerides	Improves (the measure goes down)		3 studies	23 people
Oxidative Stress Biomarkers	Improves (the measure goes down)		2 studies	23 people
LDL Oxidation	Improves (the measure goes down)			23 people
Low-density lipoprotein (LDL)	Improves (the measure goes down)			23 people
Total cholesterol	Improves (the measure goes down)			23 people
vLDL-C	Improves (the measure goes down)			23 people

Cognitive Improvement

Attention
Blood Pressure: improves
C-Reactive Protein (CRP): improves

Cognitive Improvement: outcomes studied for Cocoa Extract
Outcome	Effect	Size	Studies	People
Attention No effect		NoneNo effect	2 studies	178 people
Blood Pressure	Improves (the measure goes down)		10 studies	90 people
C-Reactive Protein (CRP)	Improves (the measure goes down)		1 study	90 people
Cerebral Blood Flow	Improves (the measure goes up)			16 people
Cerebral Oxygenation	Improves (the measure goes up)			16 people
Cognition	Improves (the measure goes up)			90 people
Fatigue Symptoms	Improves (the measure goes down)			16 people
Memory	Improves (the measure goes up)			162 people
Stress Signs and Symptoms	Improves (the measure goes down)			72 people
Subjective Well-Being	Improves (the measure goes up)			162 people
Working Memory	Improves (the measure goes up)			162 people

Mood Improvement

Attention
Memory: improves
Stress Signs and Symptoms: improves

Mood Improvement: outcomes studied for Cocoa Extract
Outcome	Effect	Size	Studies	People
Attention No effect		NoneNo effect	2 studies	72 people
Memory	Improves (the measure goes up)			72 people
Stress Signs and Symptoms	Improves (the measure goes down)			72 people
Subjective Well-Being	Improves (the measure goes up)			72 people
Working Memory	Improves (the measure goes up)			72 people

Heart Failure

Heart Failure Risk
Mitochondrial Protection: improves

Heart Failure: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Heart Failure Risk No effect		NoneNo effect	1 study	106,109 people
	Mitochondrial Protection	Improves (the measure goes up)		1 study	5 people

Coronary Artery Disease (CAD)

C-Reactive Protein (CRP)
High-density lipoprotein (HDL): improves
Platelet Aggregation: changes; see studies

Coronary Artery Disease (CAD): outcomes studied for Cocoa Extract
Outcome	Effect	Size	Studies	People
C-Reactive Protein (CRP) No effect		NoneNo effect	1 study	28 people
High-density lipoprotein (HDL)	Improves (the measure goes up)		13 studies	28 people
Platelet Aggregation	Changes; see studies		2 studies	28 people
Low-density lipoprotein (LDL)	Improves (the measure goes down)			28 people

Metabolic Health

Adiponectin
High-density lipoprotein (HDL): improves
Blood Pressure: improves

Metabolic Health: outcomes studied for Cocoa Extract
Outcome	Effect	Size	Studies	People
Adiponectin No effect		NoneNo effect		20 people
High-density lipoprotein (HDL)	Improves (the measure goes up)		13 studies	439 people
Blood Pressure	Improves (the measure goes down)		10 studies	253 people
Blood glucose	Improves (the measure goes down)		5 studies	61 people
Triglycerides	Improves (the measure goes down)		3 studies	439 people
Blood Flow	Improves (the measure goes up)		2 studies	100 people
Oxidative Stress Biomarkers	Improves (the measure goes down)		2 studies	76 people
Platelet Aggregation	Changes; see studies		2 studies	148 people
Blood Lactate (Exercise)	Changes; see studies		1 study	14 people
C-Reactive Protein (CRP)	Improves (the measure goes down)		1 study	41 people
Fat Oxidation	Improves (the measure goes up)		1 study	83 people
Adrenocorticotropic Hormone	Improves (the measure goes up)			34 people
Aerobic Exercise Metrics	Improves (the measure goes up)			28 people
Anaerobic Capacity	Improves (the measure goes up)			14 people
Cell Adhesion Factors	Improves (the measure goes down)			20 people
Cortisol	Improves (the measure goes down)			34 people
Exercise-Induced Oxidation	Changes; see studies			34 people
Glucagon	Changes; see studies			20 people
Glycemic Control	Improves (the measure goes up)			115 people
Heart Rate	Improves (the measure goes down)			98 people
Homocysteine	Improves (the measure goes down)			19 people
IL-1Ra	Improves (the measure goes down)			20 people
Insulin	Changes; see studies			77 people
Interleukin 10	Improves (the measure goes up)			20 people
Interleukin 6	Improves (the measure goes down)			34 people
Leptin	Improves (the measure goes up)			20 people
Low-density lipoprotein (LDL)	Improves (the measure goes down)			439 people
Neutrophil Count	Improves (the measure goes up)			34 people
Plasma Vitamin E	Improves (the measure goes up)			28 people
Rating of Perceived Exertion	Improves (the measure goes up)			34 people
TNF-Alpha	Improves (the measure goes down)			20 people
Total cholesterol	Improves (the measure goes down)			570 people
Uric Acid	Improves (the measure goes down)			19 people
Weight	Improves (the measure goes down)			84 people

High Blood Pressure

Adiponectin
High-density lipoprotein (HDL): improves
Blood Pressure: improves

High Blood Pressure: outcomes studied for Cocoa Extract
Outcome	Effect	Size	Studies	People
Adiponectin No effect		NoneNo effect		20 people
High-density lipoprotein (HDL)	Improves (the measure goes up)		13 studies	107 people
Blood Pressure	Improves (the measure goes down)		10 studies	1,772 people
Blood glucose	Improves (the measure goes down)		5 studies	60 people
Triglycerides	Improves (the measure goes down)		3 studies	79 people
Blood Flow	Improves (the measure goes up)		2 studies	100 people
Platelet Aggregation	Changes; see studies		2 studies	28 people
C-Reactive Protein (CRP)	Improves (the measure goes down)		1 study	87 people
Body Fat	Improves (the measure goes down)			56 people
Cell Adhesion Factors	Improves (the measure goes down)			60 people
Food Intake	Changes; see studies			30 people
Glycemic Control	Improves (the measure goes up)			79 people
Homocysteine	Improves (the measure goes down)			19 people
Insulin	Changes; see studies			59 people
Interleukin 6	Improves (the measure goes down)			20 people
LDL Oxidation	Improves (the measure goes down)			20 people
Leptin	Improves (the measure goes up)			20 people
Low-density lipoprotein (LDL)	Improves (the measure goes down)			107 people
Muscle Mass	Improves (the measure goes up)			20 people
Nitric Oxide	Improves (the measure goes up)			30 people
TNF-Alpha	Improves (the measure goes down)			40 people
Total cholesterol	Improves (the measure goes down)			79 people
Uric Acid	Improves (the measure goes down)			19 people
Weight	Improves (the measure goes down)			76 people

Aerobic Exercise Performance

Adrenocorticotropic Hormone
Oxidative Stress Biomarkers: improves
Fat Oxidation: improves

Aerobic Exercise Performance: outcomes studied for Cocoa Extract
Outcome	Effect	Size	Studies	People
Adrenocorticotropic Hormone No effect		NoneNo effect		20 people
Oxidative Stress Biomarkers	Improves (the measure goes down)		2 studies	28 people
Fat Oxidation	Improves (the measure goes up)		1 study	20 people
Aerobic Exercise Metrics	Improves (the measure goes up)			28 people
Cortisol	Improves (the measure goes down)			20 people
Exercise-Induced Oxidation	Changes; see studies			20 people
Glucagon	Changes; see studies			20 people
Heart Rate	Improves (the measure goes down)			20 people
Insulin	Changes; see studies			20 people
Interleukin 10	Improves (the measure goes up)			20 people
Interleukin 6	Improves (the measure goes down)			20 people
Neutrophil Count	Improves (the measure goes up)			20 people
Plasma Vitamin E	Improves (the measure goes up)			28 people
Rating of Perceived Exertion	Improves (the measure goes up)			20 people

General Athletic Performance

Adrenocorticotropic Hormone
Blood Lactate (Exercise): changes; see studies
Fat Oxidation: improves

General Athletic Performance: outcomes studied for Cocoa Extract
Outcome	Effect	Size	Studies	People
Adrenocorticotropic Hormone No effect		NoneNo effect		34 people
Blood Lactate (Exercise)	Changes; see studies		1 study	14 people
Fat Oxidation	Improves (the measure goes up)		1 study	34 people
Anaerobic Capacity	Improves (the measure goes up)			14 people
Cortisol	Improves (the measure goes down)			34 people
Exercise-Induced Oxidation	Changes; see studies			34 people
Glucagon	Changes; see studies			20 people
Heart Rate	Improves (the measure goes down)			34 people
IL-1Ra	Improves (the measure goes down)			20 people
Insulin	Changes; see studies			34 people
Interleukin 10	Improves (the measure goes up)			20 people
Interleukin 6	Improves (the measure goes down)			34 people
Neutrophil Activity	Improves (the measure goes up)			14 people
Neutrophil Count	Improves (the measure goes up)			34 people
Rating of Perceived Exertion	Improves (the measure goes up)			34 people

Immune Health

Adrenocorticotropic Hormone
Fat Oxidation: improves
Cortisol: improves

Immune Health: outcomes studied for Cocoa Extract
Outcome	Effect	Size	Studies	People
Adrenocorticotropic Hormone No effect		NoneNo effect		14 people
Fat Oxidation	Improves (the measure goes up)		1 study	14 people
Cortisol	Improves (the measure goes down)			14 people
Exercise-Induced Oxidation	Changes; see studies			14 people
Heart Rate	Improves (the measure goes down)			14 people
Insulin	Changes; see studies			14 people
Interleukin 6	Improves (the measure goes down)			14 people
Neutrophil Activity	Improves (the measure goes up)			14 people
Neutrophil Count	Improves (the measure goes up)			14 people

Soccer Performance

Aerobic Exercise Metrics
Oxidative Stress Biomarkers: improves

Soccer Performance: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Aerobic Exercise Metrics No effect		NoneNo effect		28 people
	Oxidative Stress Biomarkers	Improves (the measure goes down)		2 studies	28 people

General Gut Health

Triglycerides: improves

General Gut Health: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Triglycerides	Improves (the measure goes down)		3 studies	22 people

Acne

Acne Symptoms: improves

Acne: outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Acne Symptoms	Improves (the measure goes down)		1 study	13 people

Chronic Kidney Disease (CKD)

Kidney Oxygenation: improves

Chronic Kidney Disease (CKD): outcomes studied for Cocoa Extract
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Kidney Oxygenation	Improves (the measure goes up)		1 study	10 people

Key findings

Blood FlowObesityImproves (the measure goes up)
Blood PressureGlaucomaImproves (the measure goes down)
AdrenalineWorsens (the measure goes down)

Shop the evidence-backed picks

Third-party tested Cocoa Extract products, in the forms the graded studies used where we can match them.

Grade B

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Studies cited

56 studies from PubMed

Effects of cocoa products/dark chocolate on serum lipids: a meta-analysisEur J Clin Nutr · PMID 21559039
Regular consumption of a flavanol-rich chocolate can improve oxidant stress in young soccer playersClin Dev Immunol · PMID 15712594
Effect of cocoa flavanols and exercise on cardiometabolic risk factors in overweight and obese subjectsInt J Obes · PMID 18504447
Short-term administration of dark chocolate is followed by a significant increase in insulin sensitivity and a decrease in blood pressure in healthy personsAm J Clin Nutr · PMID 15755830
Cocoa consumption for 2 wk enhances insulin-mediated vasodilatation without improving blood pressure or insulin resistance in essential hypertensionAm J Clin Nutr · PMID 19064532
Blood pressure is reduced and insulin sensitivity increased in glucose-intolerant, hypertensive subjects after 15 days of consuming high-polyphenol dark chocolateJ Nutr · PMID 18716168
The effect of polyphenol-rich dark chocolate on fasting capillary whole blood glucose, total cholesterol, blood pressure and glucocorticoids in healthy overweight and obese subjectsBr J Nutr · PMID 19825207
Protective effects of flavanol-rich dark chocolate on endothelial function and wave reflection during acute hyperglycemiaHypertension · PMID 22851734
The effect of acute pre-exercise dark chocolate consumption on plasma antioxidant status, oxidative stress and immunoendocrine responses to prolonged exerciseEur J Nutr · PMID 21465244
Prebiotic evaluation of cocoa-derived flavanols in healthy humans by using a randomized, controlled, double-blind, crossover intervention studyAm J Clin Nutr · PMID 21068351
Safety and efficacy of cocoa flavanol intake in healthy adults: a randomized, controlled, double-masked trialAm J Clin Nutr · PMID 26537937
Regular dark chocolate consumption's reduction of oxidative stress and increase of free-fatty-acid mobilization in response to prolonged cyclingInt J Sport Nutr Exerc Metab · PMID 21558573
Dark chocolate inhibits platelet isoprostanes via NOX2 down-regulation in smokersJ Thromb Haemost · PMID 22066819
Influence of cocoa flavanols and procyanidins on free radical-induced human erythrocyte hemolysisClin Dev Immunol · PMID 15712596
Flavonoid-rich dark chocolate improves endothelial function and increases plasma epicatechin concentrations in healthy adultsJ Am Coll Nutr · PMID 15190043
A double-blind, placebo-controlled, randomized trial of the effects of dark chocolate and cocoa on variables associated with neuropsychological functioning and cardiovascular health: clinical findings from a sample of healthy, cognitively intact older adultsAm J Clin Nutr · PMID 18400709
Dark chocolate effect on platelet activity, C-reactive protein and lipid profile: a pilot studySouth Med J · PMID 19005437
Effects of dark chocolate and cocoa consumption on endothelial function and arterial stiffness in overweight adultsBr J Nutr · PMID 24274771
Effects of Cocoa Consumption on Cardiometabolic Risk Markers: Meta-Analysis of Randomized Controlled Trials.Nutrients · PMID 38931273
Dark chocolate intake buffers stress reactivity in humansJ Am Coll Cardiol · PMID 24681134
Effect of dark chocolate on arterial function in healthy individualsAm J Hypertens · PMID 15925737
Dose-dependent increases in flow-mediated dilation following acute cocoa ingestion in healthy older adultsJ Appl Physiol · PMID 21903881
Acute effect of oral flavonoid-rich dark chocolate intake on coronary circulation, as compared with non-flavonoid white chocolate, by transthoracic Doppler echocardiography in healthy adultsInt J Cardiol · PMID 18045712
Characterisation of hypertensive patients with improved endothelial function after dark chocolate consumptionInt J Hypertens · PMID 23533716
Blood pressure and endothelial function in healthy, pregnant women after acute and daily consumption of flavanol-rich chocolate: a pilot, randomized controlled trialNutr J · PMID 23565841
Effect of dark chocolate on nitric oxide serum levels and blood pressure in prehypertension subjectsActa Med Indones · PMID 22156352
NOX2-mediated arterial dysfunction in smokers: acute effect of dark chocolateHeart · PMID 21807659
Flavan-3-ol-enriched dark chocolate and white chocolate improve acute measures of platelet function in a gender-specific way--a randomized-controlled human intervention trialMol Nutr Food Res · PMID 23136121
The effects of flavanol-rich cocoa and aspirin on ex vivo platelet functionThromb Res · PMID 12297125
Sustained benefits in vascular function through flavanol-containing cocoa in medicated diabetic patients a double-masked, randomized, controlled trialJ Am Coll Cardiol · PMID 18510961
Alterations in skeletal muscle indicators of mitochondrial structure and biogenesis in patients with type 2 diabetes and heart failure: effects of epicatechin rich cocoaClin Transl Sci · PMID 22376256
Long-term ingestion of high flavanol cocoa provides photoprotection against UV-induced erythema and improves skin condition in womenJ Nutr · PMID 16702322
Chocolate flavanols and skin photoprotection: a parallel, double-blind, randomized clinical trialNutr J · PMID 24970388
Cocoa Flavanol Supplementation Influences Skin Conditions of Photo-Aged Women: A 24-Week Double-Blind, Randomized, Controlled TrialJ Nutr · PMID 26581682
Dark chocolate and vascular function in patients with peripheral artery disease: a randomized, controlled cross-over trialClin Hemorheol Microcirc · PMID 24531123
Dark chocolate acutely improves walking autonomy in patients with peripheral artery diseaseJ Am Heart Assoc · PMID 24990275
Cocoa reduces blood pressure and insulin resistance and improves endothelium-dependent vasodilation in hypertensivesHypertension · PMID 16027246
Consumption of high-polyphenol dark chocolate improves endothelial function in individuals with stage 1 hypertension and excess body weightInt J Hypertens · PMID 23209885
Effect of cocoa on blood pressureCochrane Database Syst Rev · PMID 28439881
Dark chocolate or tomato extract for prehypertension: a randomised controlled trialBMC Complement Altern Med · PMID 19583878
Dark chocolate for children's blood pressure: randomised trialArch Dis Child · PMID 22685047
Effect of cocoa products on blood pressure: systematic review and meta-analysis.Am J Hypertens · PMID 19910929
Effects of dark chocolate consumption on the prothrombotic response to acute psychosocial stress in healthy menThromb Haemost · PMID 25208561
Effects of dark chocolate in a population of normal weight obese women: a pilot studyEur Rev Med Pharmacol Sci · PMID 23893195
Effects of chocolate, cocoa, and flavan-3-ols on cardiovascular health: a systematic review and meta-analysis of randomized trialsAm J Clin Nutr · PMID 22301923
Chocolate consumption and cardiometabolic disorders: systematic review and meta-analysis.BMJ · PMID 21875885
Relationship between chocolate consumption and overall and cause-specific mortality, systematic review and updated meta-analysis.Eur J Epidemiol · PMID 35460393
The effect of flavanol-rich cocoa on the fMRI response to a cognitive task in healthy young peopleJ Cardiovasc Pharmacol · PMID 16794461
Cocoa polyphenols enhance positive mood states but not cognitive performance: a randomized, placebo-controlled trialJ Psychopharmacol · PMID 23364814
Dark chocolate consumption improves leukocyte adhesion factors and vascular function in overweight menFASEB J · PMID 24302679
Effects of cocoa powder and dark chocolate on LDL oxidative susceptibility and prostaglandin concentrations in humansAm J Clin Nutr · PMID 11684527
Postprandial effects of dark chocolate on portal hypertension in patients with cirrhosis: results of a phase 2, double-blind, randomized controlled trialAm J Clin Nutr · PMID 22811444
The short-term effect of flavonoid-rich dark chocolate on retinal vessel diameter in glaucoma patients and age-matched controlsActa Ophthalmol · PMID 24628966
Effect of dark chocolate on renal tissue oxygenation as measured by BOLD-MRI in healthy volunteersClin Nephrol · PMID 23557792
Double-blind, Placebo-controlled Study Assessing the Effect of Chocolate Consumption in Subjects with a History of Acne VulgarisJ Clin Aesthet Dermatol · PMID 24847404
Chocolate Consumption and Risk of Heart Failure: A Meta-Analysis of Prospective StudiesNutrients · PMID 28425931

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