Condition

Lung Cancer

Lung cancer is a disease in which cells in the lungs grow out of control and form tumors that can interfere with breathing and spread elsewhere. Omega-3 fatty acids and vitamin D have moderate evidence among supplements, yet fish oil studies found no clear difference in C-reactive protein, an inflammation marker. Those studies were tiny, and beta-carotene in smokers went the other way: trials found a higher risk of lung cancer.

Sources: PMID 15100717; PMID 12654170

Supplements studied: 4
Graded outcomes: 3
Trials: 2
People studied: 2,314

Evidence by supplement

Strong
Moderate
Limited
Very limited

4 supplements

Laughter

Laughter: outcomes studied for Lung Cancer
Grade	Outcome	Effect	Size	Studies	People
	Anxiety Symptoms Large Improvement	Improves (the measure goes down)	Large effect		128 people
	Stress Signs and Symptoms	Improves (the measure goes down)		1 study	177 people
Studies that measured stress signs and symptoms The Efficacy of Laughter Therapy on Psychological Symptoms in People With Cancer: A Systematic Review and Meta-Analysis of Randomized Controlled Studies.Psychooncology · PMID 39472305
	Depression Symptoms	Improves (the measure goes down)			304 people

Fish Oil

Fish Oil: outcomes studied for Lung Cancer
Grade	Outcome	Effect	Size	Studies	People
	C-Reactive Protein (CRP) No effect		NoneNo effect	4 studies	33 people
Studies that measured c-reactive protein (crp) Intake of n-3 fatty acids from fish does not lower serum concentrations of C-reactive protein in healthy subjectsEur J Clin Nutr · PMID 15100717 The effect of dietary n-3 fatty acids on serum concentrations of C-reactive protein: a dose-response studyBr J Nutr · PMID 12654170 Effect of Omega-3 fatty acid supplementation on markers of platelet and endothelial function in patients with peripheral arterial diseaseAtherosclerosis · PMID 22296885 and 1 more on the Fish Oil page
	Inflammation	Improves (the measure goes down)		4 studies	33 people
Studies that measured inflammation Effects of marine omega-3 fatty acids on serum systemic and vascular inflammation markers and oxidative stress in hemodialysis patientsAnn Nutr Metab · PMID 21757893 Influence of very long-chain n-3 fatty acids on plasma markers of inflammation in middle-aged menProstaglandins Leukot Essent Fatty Acids · PMID 18403189 Effects of omega-3 fatty acids on postprandial triglycerides and monocyte activationAtherosclerosis · PMID 23017356 and 1 more on the Fish Oil page

Beta-Carotene

Lung Cancer Incidence (Smokers): worsens

Beta-Carotene: outcomes studied for Lung Cancer
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Lung Cancer Incidence (Smokers) HARMFUL: ATBC (PMID: 8901854) showed 18% increase; CARET showed 28% increase. Meta-analysis: 24% increased risk in smokers	Worsens (the measure goes up)	Moderate effect		47,447 people

Inositol

Lung Cancer Risk: changes; see studies

Inositol: outcomes studied for Lung Cancer
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Lung Cancer Risk	Changes; see studies		1 study	10 people
Studies that measured lung cancer risk A phase I study of myo-inositol for lung cancer chemopreventionCancer Epidemiol Biomarkers Prev · PMID 16896044

Key findings

Anxiety SymptomsLaughterImproves (the measure goes down)
C-Reactive Protein (CRP)Fish Oil
Lung Cancer Incidence (Smokers)Beta-CaroteneWorsens (the measure goes up)

Safety notes in the studies

Meta-analysis: 24% increased risk in smokers

The Lung Cancer Supportive Care protocol

2 primary supplements · 6 supporting supplements

Omega-3 Fatty Acids2–4 g EPA+DHA daily
Vitamin D2,000–4,000 IU daily (based on blood levels)

See the full protocol

Studies cited

1 study from PubMed

Systematic review and meta-analysis of breathing exercises effects on lung function and quality of life in postoperative lung cancer patients.J Thorac Dis · PMID 39144355