The Claim
Daily supplementation with 20 mg of beta carotene for 5 to 8 years increases the incidence of lung cancer by 18% and total mortality by 8% in male smokers aged 50 to 69 compared to placebo.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
In male smokers aged 50 to 69, taking 20 mg of beta carotene daily for 5 to 8 years results in an 18% higher rate of lung cancer and an 8% higher rate of death from any cause compared to taking a placebo.
See the scientific wording
Daily supplementation with 20 mg of beta carotene for 5 to 8 years increases the incidence of lung cancer by 18% and total mortality by 8% in male smokers aged 50 to 69, compared to placebo, indicating a harmful effect of this supplement in this population.
In smokers, beta carotene breaks down into chemicals that attack DNA in lung cells and stop the cells from fixing the damage, leading to cancer and death.
What the research says
1 studyIn a big study of smoking men, those who took a daily beta carotene pill got more lung cancer and were more likely to die than those who took a sugar pill. So the supplement didn’t help—it hurt.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.