Condition
Lower Respiratory Tract Infection
Lower respiratory tract infections affect the bronchi and lungs, below the voice box, and include bronchitis, bronchiolitis and pneumonia. Vitamin C and vitamin D are the leading candidates, yet vitamin D showed no clear difference in lower respiratory infection risk among 5,110 people, and a nasal resveratrol solution showed none for upper infections in 39 children. Evidence for each is very limited, and the other supplements studied have little direct trial data here.
Sources: PMID 39064639
- Supplements studied
- 5
- Graded outcomes
- 4
- Trials
- 6
- People studied
- 5,860
Evidence by supplement
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| All-Cause Mortality No effect | NoneNo effect | 2 studies | 451 people | |||
| Weight | Improves (the measure goes down) | 1 study | 451 people | |||
Studies that measured weight | ||||||
| Hemoglobin | Improves (the measure goes up) | 451 people | ||||
| Immunity | Improves (the measure goes up) | 902 people | ||||
| Upper Respiratory Tract Infection Risk | Changes; see studies | 451 people | ||||
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Upper Respiratory Tract Infection Risk No effect | NoneNo effect | 1 study | 39 people | |||
Studies that measured upper respiratory tract infection risk | ||||||
| Upper Respiratory Tract Infection Symptoms | Improves (the measure goes down) | 39 people | ||||
Lactobacillus Casei
- Immunity
- Immunoglobulin A: improves
- Upper Respiratory Tract Infection Risk: changes; see studies
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Immunity No effect | NoneNo effect | 47 people | ||||
| Immunoglobulin A | Improves (the measure goes up) | 2 studies | 47 people | |||
| Upper Respiratory Tract Infection Risk | Changes; see studies | 47 people | ||||
Vitamin D
- Lower Respiratory Tract Infection Risk
- Upper Respiratory Tract Infection Risk: changes; see studies
- Upper Respiratory Tract Infection Symptoms: improves
Vitamin C
- Upper Respiratory Tract Infection Symptoms: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Upper Respiratory Tract Infection Symptoms | Improves (the measure goes down) | 24 studies | 57 people | |||
Studies that measured upper respiratory tract infection symptoms | ||||||
Key findings
- All-Cause Mortality
- Upper Respiratory Tract Infection Risk
- Immunity
The Lower Respiratory Tract Infection Support protocol
2 primary supplements · 3 supporting supplements
Shop the evidence-backed picks
Support alongside medical care. These supplements are not a treatment for Lower Respiratory Tract Infection. If you are being treated for it, talk to your clinician before adding one: supplements can interact with medicines.
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Studies cited
100 studies from PubMed
- Effect of vitamin D supplementation for major adverse cardiovascular events: a meta-analysis based on randomised controlled trials.
- Resveratrol: A Potential Therapeutic Natural Polyphenol for Neurodegenerative Diseases Associated with Mitochondrial Dysfunction
- Resveratrol: An Overview of Clinical Trials in Human Cancer Prevention and Treatment
- Resveratrol and Its Analogs: Potent Agents to Reverse Epithelial-to-Mesenchymal Transition in Tumors
- Resveratrol and Sirtuins: A Story of Living Long Healthy Life
- Therapeutic Potential of Resveratrol in Alzheimer's Disease: A Review of the Evidence
- Resveratrol as a Chemopreventive Agent: A Promising Molecule for Fighting Cancer
- Resveratrol and Health - A Comprehensive Review of Human Clinical Trials
- Resveratrol: A Double-Edged Sword in Health Benefits
- Resveratrol and Caloric Restriction: The Role of Sirtuins in Aging and Age-Related Diseases
- The Multitarget Activity of Natural Bioactive Compounds in Parkinson's Disease: Role of Resveratrol
- Resveratrol: A New Treatment for Diseases Associated with Oxidative Stress
- Resveratrol-Based Compounds and Neurodegeneration: Recent Insight in Multitarget Neuroprotection
- An Overview of the Anticancer Properties of Resveratrol
- Optimal Vitamin D Status: Evidence and Guidelines
- Vitamin D and Cancer Prevention: A Comprehensive Review
- An Update on Resveratrol and Diabetes: From Metabolism to Clinical Trial Results
- Effects of Vitamin D Supplementation on Musculoskeletal Health: A Systematic Review and Meta-Analysis
- Vitamin D and Prevention of Respiratory Tract Infections: A Systematic Review and Meta-Analysis
- Effects of Vitamin D Supplementation on Depression: A Systematic Review and Meta-Analysis
- Vitamin D and Immune Function: A Review
- Vitamin D Supplementation for Prevention of Mortality: A Meta-Analysis
- Vitamin D Supplementation During Pregnancy: Safety and Efficacy Review
- Vitamin D Supplementation: A Comprehensive Review of Efficacy for Various Health Outcomes
- Vitamin D Deficiency: Global Health Perspective
- Vitamin D and Cardiovascular Disease: A Review of Evidence
- Vitamin D and Bone Health in Adults: A Systematic Review
- Vitamin D3 supplementation does not modify cardiovascular risk profile of adults with inadequate vitamin D status
- Resveratrol Blunts the Positive Effects of Exercise Training on Cardiovascular Health in Aged Men
- Association of A1C levels with vitamin D status in U.S. adults: data from the National Health and Nutrition Examination Survey
- Serum 25-hydroxyvitamin D, ethnicity, and blood pressure in the Third National Health and Nutrition Examination Survey
- Influence of vitamin C supplementation on oxidative and immune changes after an ultramarathon
- The influence of probiotic supplementation on gut permeability in patients with metabolic syndrome: an open label, randomized pilot study
- Daily probiotic's (Lactobacillus casei Shirota) reduction of infection incidence in athletes
- Effect of a probiotics supplementation on respiratory infections and immune and hormonal parameters during intense military training
- Cardioprotection by resveratrol: A human clinical trial in patients with stable coronary artery disease
- The effects of resveratrol on glycemic control and cardiometabolic parameters in patients with T2DM: A systematic review and meta-analysis.
- Evidence-based nutritional and pharmacological interventions targeting chronic low-grade inflammation in middle-age and older adults: A systematic review and meta-analysis.
- Can resveratrol supplement change inflammatory mediators? A systematic review and meta-analysis on randomized clinical trials.
- Resveratrol supplementation efficiently improves endothelial health: A systematic review and meta-analysis of randomized controlled trials.
- Trans-resveratrol alters mammary promoter hypermethylation in women at increased risk for breast cancer
- Effects of resveratrol on cerebral blood flow variables and cognitive performance in humans: a double-blind, placebo-controlled, crossover investigation
- Resveratrol improves insulin sensitivity, reduces oxidative stress and activates the Akt pathway in type 2 diabetic patients
- The efficacy of resveratrol supplementation on inflammation and oxidative stress in type-2 diabetes mellitus patients: randomized double-blind placebo meta-analysis.
- Pilot Study of Resveratrol in Older Adults With Impaired Glucose Tolerance
- Effect of resveratrol on glucose control and insulin sensitivity: a meta-analysis of 11 randomized controlled trials.
- Resveratrol supplementation and type 2 diabetes: a systematic review and meta-analysis
- Influence of Age and Dose on the Effect of Resveratrol for Glycemic Control in Type 2 Diabetes Mellitus: Systematic Review and Meta-Analysis.
- Resveratrol treatment as an adjunct to pharmacological management in type 2 diabetes mellitus--systematic review and meta-analysis.
- Effects of Resveratrol on Metabolic Indicators in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis.
- Efficacy of resveratrol supplementation in patients with nonalcoholic fatty liver disease: A systematic review and meta-analysis of clinical trials
- The effects of resveratrol supplementation in patients with type 2 diabetes, metabolic syndrome, and nonalcoholic fatty liver disease: an umbrella review of meta-analyses of randomized controlled trials
- Effect of Resveratrol on Blood Lipid Levels in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis.
- Fine wine or sour grapes? A systematic review and meta-analysis of the impact of red wine polyphenols on vascular health
- The effects of resveratrol supplementation on biomarkers of inflammation and oxidative stress among patients with metabolic syndrome and related disorders: a systematic review and meta-analysis of randomized controlled trials.
- Resveratrol supplementation significantly influences obesity measures: a systematic review and dose-response meta-analysis of randomized controlled trials.
- Resveratrol may mildly improve renal function in the general adult population: A systematic review and meta-analysis of randomized controlled clinical trials.
- Calorie restriction-like effects of 30 days of resveratrol supplementation on energy metabolism and metabolic profile in obese humans
- Effects of resveratrol supplementation on liver enzymes: A systematic review and meta-analysis of randomised controlled trials.
- The Effects of Resveratrol Supplementation on Endothelial Function and Blood Pressures Among Patients with Metabolic Syndrome and Related Disorders: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
- Resveratrol supplementation does not augment performance adaptations or fibre-type-specific responses to high-intensity interval training in humans
- Resveratrol-containing gel for the treatment of acne vulgaris: a single-blind, vehicle-controlled, pilot study
- Efficacy of Resveratrol Supplementation on Glucose and Lipid Metabolism: A Meta-Analysis and Systematic Review
- Efficacy of resveratrol in women with polycystic ovary syndrome: a systematic review and meta-analysis of randomized clinical trials.
- Effects of resveratrol on polycystic ovarian syndrome: a systematic review and meta-analysis of randomized controlled trials.
- The effect of dietary (poly)phenols on exercise-induced physiological adaptations: A systematic review and meta-analysis of human intervention trials
- Efficacy of resveratrol supplementation on liver enzymes in patients with non-alcoholic fatty liver disease: A systematic review and meta-analysis
- Efficacy and safety of biophenol-rich nutraceuticals in adults with inflammatory gastrointestinal diseases or irritable bowel syndrome: A systematic literature review and meta-analysis
- Effects of resveratrol supplementation on renal function in adults: a systematic review and dose-response meta-analysis.
- Oral resveratrol in adults with knee osteoarthritis: A randomized placebo-controlled trial (ARTHROL).
- Effects of Nasal Solution Incorporating Resveratrol and Carboxymethyl-Β-Glucan in Preschool Non-Atopic Children with Wheezing.
- A Systematic Review and Meta-Analysis of Randomized Controlled Trials on the Impact of Resveratrol Supplementation on Anthropometric Indices in Patients With Type 2 Diabetes.
- Ascorbic acid supplementation improves skeletal muscle oxidative stress and insulin sensitivity in people with type 2 diabetes: Findings of a randomized controlled study
- Vitamin C may have similar beneficial effects to Gemfibrozil on serum high-density lipoprotein-cholesterol in type 2 diabetic patients
- Supplementation of vitamin C reduces blood glucose and improves glycosylated hemoglobin in type 2 diabetes mellitus: a randomized, double-blind study
- The effect of vitamin C supplementation on diabetic hyperlipidaemia: a double blind, crossover study
- Unchanged renal haemodynamics following high dose ascorbic acid administration in normoalbuminuric IDDM patients
- Ascorbic acid supplementation improves postprandial glycaemic control and blood pressure in individuals with type 2 diabetes: Findings of a randomized cross-over trial
- Effects of eicosapentaenoic acid and vitamin C on glycemic indices, blood pressure, and serum lipids in type 2 diabetic Iranian males
- Effect of vitamin C on inflammation and metabolic markers in hypertensive and/or diabetic obese adults: a randomized controlled trial
- Does short-term vitamin C reduce cardiovascular risk in type 2 diabetes?
- Effects of atorvastatin and vitamin C on forearm hyperaemic blood flow, asymmentrical dimethylarginine levels and the inflammatory process in patients with type 2 diabetes mellitus
- Effect of vitamin C supplementation on postprandial oxidative stress and lipid profile in type 2 diabetic patients
- High-dose oral vitamin C partially replenishes vitamin C levels in patients with Type 2 diabetes and low vitamin C levels but does not improve endothelial dysfunction or insulin resistance
- Vitamin C and the common cold: a double-blind trial
- Ascorbic acid and the common cold
- Preventing the common cold with a vitamin C supplement: a double-blind, placebo-controlled survey
- Vitamin C and the common cold
- Winter illness and vitamin C: the effect of relatively low doses
- Ascorbic acid for the common cold. A prophylactic and therapeutic trial
- Therapeutic effect of vitamin C. A co-twin control study
- A randomized controlled trial of the therapeutic effect of vitamin C in the common cold
- Vitamin C and the common cold: a second MZ Cotwin control study
- Trial of ascorbic acid in prevention of colds
- Mega-dose vitamin C in treatment of the common cold: a randomised controlled trial
- A controlled clinical trial of ascorbic acid for the common cold
- The effectiveness of vitamin C in preventing and relieving the symptoms of virus-induced respiratory infections
- Vitamin C prophylaxis in marine recruits
- L-Ascorbic acid and D-isoascorbic acid in a common cold survey
- A randomized controlled trial of vitamin C in the prevention and amelioration of the common cold