The first global review of complementary medicines for weight loss in 16 years suggests that their use cannot be justified on the basis of current evidence.
The findings of two studies, being presented at The European Congress on Obesity (ECO) held online this year, suggest that although some herbal and dietary supplements show statistically greater weight loss than placebo, it is not enough to benefit health, and the authors call for more research into their long-term safety.
"Over-the-counter herbal and dietary supplements promoted for weight loss are increasingly popular, but unlike pharmaceutical drugs, clinical evidence for their safety and effectiveness is not required before they hit the market", said lead author Erica Bessell from the University of Sydney in Australia.
"Our rigorous assessment of the best available evidence finds that there is insufficient evidence to recommend these supplements for weight loss. Even though most supplements appear safe for short term consumption, they are not going to provide weight loss that is clinically meaningful."
The report covered herbal supplements, containing a whole plant or combinations of plants as the active ingredient, and dietary supplements containing naturally occurring isolated compounds from plants and animal products, such as fibres, fats, proteins, and antioxidants. They can be purchased as pills, powders and liquids.
Estimates suggest that 15% of Americans trying to lose weight have tried a weight loss supplement, a $41 billion (P2 trillion) global industry in 2020. Despite their increasing popularity, it has been 16 years since the last review of the scientific literature on all available herbal and dietary supplements.
"Herbal and dietary supplements might seem like a quick-fix solution to weight problems, but people need to be aware of how little we actually know about them," said Bessell.
"Very few high-quality studies have been done on some supplements with little data on long-term effectiveness. What's more, many trials are small and poorly designed, and some don't report on the composition of the supplements being investigated. The tremendous growth in the industry and popularity of these products underscores the urgency for conducting larger more rigorous studies to have reasonable assurance of their safety and effectiveness for weight loss." (ANI)