Avoid unverified pills, coffee, sweets, or preserved fruit promising rapid weight loss
Sibutramine is a drug repeatedly found undeclared in slimming products. China withdrew it in 2010. In a trial of older overweight or obese people with cardiovascular disease or diabetes, it increased nonfatal heart attacks by about 28% and nonfatal strokes by about 36%, while producing only 1.7 kg of additional weight loss after randomization. A product may already have been consumed long before testing reveals an undeclared ingredient.
What it takes
Nothing; avoiding these products saves money. The challenge is resisting promises of losing several pounds in a week.
What you may gain
SCOUT randomized 9,804 people aged over 55 who were overweight or obese and had cardiovascular disease or type 2 diabetes. Mean treatment duration was 3.4 years. The primary composite outcome comprised nonfatal myocardial infarction, nonfatal stroke, resuscitated cardiac arrest, and cardiovascular death. It occurred in 11.4% versus 10.0%, HR 1.16, 95% CI 1.03–1.31, P=0.02. Nonfatal myocardial infarction occurred in 4.1% versus 3.2%, HR 1.28, 95% CI 1.04–1.57. Nonfatal stroke occurred in 2.6% versus 1.9%, HR 1.36, 95% CI 1.04–1.77. Cardiovascular and all-cause mortality did not increase. After randomization, the sibutramine group lost an additional 1.7 kg on average. China's former drug regulator concluded that weight-loss treatment risks outweighed benefits and in October 2010 ordered production, sale, and use of sibutramine preparations and ingredients to stop. Both sibutramine and phenolphthalein are prohibited additives in food, including health foods.
Context & considerations
SCOUT studied a high-risk population with existing cardiovascular disease or diabetes, so it does not establish the same risk in healthy young people. The regulator nevertheless withdrew the drug after its overall benefit–risk assessment. Another undeclared ingredient, phenolphthalein, is a laxative; prolonged excessive use can disturb electrolytes and contribute to arrhythmias. Approved prescription weight-loss medicines have verifiable authorization numbers and require a legitimate prescribing route. Food marketed as coffee, sweets, plums, or meal replacements while promising dramatic rapid effects is a warning sign, but an apparent effect alone does not prove adulteration. The original inferred adulteration from such claims more categorically. The national regulator's page for document Guoshiyaojianban [2010] No. 432 repeatedly returned HTTP 412 during source research, so the provincial regulator's account is cited instead; it explicitly confirms the benefit–risk judgment and October 2010 withdrawal.
Research & references
James WPT et al. (2010). Effect of sibutramine on cardiovascular outcomes in overweight and obese subjects. New England Journal of Medicine. https://doi.org/10.1056/NEJMoa1003114; Tianjin Municipal Market Regulation Commission. Warning about illegal addition of sibutramine hydrochloride and phenolphthalein to foods. https://scjg.tj.gov.cn/tjsscjdglwyh_52651/hdpt/cjwtyxfts/202007/t20200720_2972549.html