Myths vs facts: COMT and weight loss

COMT (catechol-O-methyltransferase) breaks down dopamine, influencing reward, appetite, and energy balance. The common Val158Met variant alters enzyme activity: Val/Val (high activity) vs. Met/Met (low activity). Myth: Your COMT variant directly determines weight loss success. Fact: Associations are weak and inconsistent. Some studies link Met/Met to slightly lower BMI, others find no effect. Lifestyle factors (diet, exercise, stress) dominate. Claims that supplements like green tea extract or methyl donors can 'optimize' COMT for weight loss lack robust human evidence. While COMT may modulate dopamine-related eating behavior, its effect size is small. A DNA test can provide insight, but it is not a weight-loss roadmap. Evidence is mixed, with many candidate-gene studies not replicating in large GWAS. Practical advice: focus on overall healthy habits rather than trying to 'hack' a single gene.