营销话术证据 B · meta 分析
胖是基因决定的, 改不了
真相
可遗传度是群体统计不是个人判决. 基因给倾向不给终点; 同一基因组在不同环境里体重天差地别 (Loos & Yeo 2022). 环境与行为有巨大空间.
机制速览
胖是因为懒和馋，不对：食欲、饱腹、奖赏的个体差异有一部分写在基因里，把胖瘦等同于道德，既不科学，也没用。基因决定一切、努力没用，也不对：可遗传度是人群的统计，不是对个人的判决；同一个基因组在不同环境里，体重可以差得很远，环境和行为有很大的空间。
来源（3）
- Fothergill, E., Guo, J., Howard, L., Kerns, J. C., Knuth, N. D., Brychta, R., Chen, K. Y., Skarulis, M. C., Walter, M., Walter, P. J., & Hall, K. D. (2016). Persistent metabolic adaptation 6 years after 'The Biggest Loser' competition. Obesity, 24(8), 1612–1619. 14 of the 16 original 'Biggest Loser' competitors re-measured 6 years later (DXA, indirect calorimetry). End of the 30-week competition: weight -58.3 kg, resting metabolic rate (RMR) -610 kcal/day. At 6 years: 41.0 kg regained, RMR still 704 kcal/day below baseline, and metabolic adaptation (RMR residual after adjusting for body composition and age) -499 ± 207 kcal/day. Regain was not correlated with metabolic adaptation at the competition's end (r = -0.1, P = 0.75), but those maintaining more weight loss at 6 years had greater concurrent metabolic slowing (r = 0.59, P = 0.025); the authors call adaptation a proportional but incomplete response to contemporaneous efforts to reduce weight (abstract, PMID 27136388).
- Sumithran, P., Prendergast, L. A., Delbridge, E., Purcell, K., Shulkes, A., Kriketos, A., & Proietto, J. (2011). Long-term persistence of hormonal adaptations to weight loss. The New England Journal of Medicine, 365(17), 1597–1604. 50 overweight or obese adults without diabetes on a 10-week very-low-energy diet; mean loss 13.5 kg. Measured at baseline, 10 and 62 weeks: leptin, ghrelin, PYY, GIP, GLP-1, amylin, pancreatic polypeptide, CCK, insulin and subjective appetite. At 62 weeks, leptin, PYY, CCK, insulin, ghrelin, GIP, pancreatic polypeptide and hunger still differed significantly from baseline; GLP-1 and amylin are not in that list. No thyroid hormone or energy-expenditure measure is reported in the abstract (abstract, PMID 22029981).
- Loos, R. J. F., & Yeo, G. S. H. (2022). The genetics of obesity: from discovery to biology. Nature Reviews Genetics, 23(2), 120-133. Polygenic (common) and monogenic (rare) obesity share genetic and biological underpinnings, pointing to a central role for the brain in body-weight control.