Dietary supplements for improving body composition and reducing body weight: where is the evidence?

Int J Sport Nutr Exerc Metab. 2012 Apr;22(2):139-54. doi: 10.1123/ijsnem.22.2.139.


Weight-loss supplements typically fall into 1 of 4 categories depending on their hypothesized mechanism of action: products that block the absorption of fat or carbohydrate, stimulants that increase thermogenesis, products that change metabolism and improve body composition, and products that suppress appetite or give a sense of fullness. Each category is reviewed, and an overview of the current science related to their effectiveness is presented. While some weight-loss supplements produce modest effects (<2 kg weight loss), many have either no or few randomized clinical trials examining their effectiveness. A number of factors confound research results associated with the efficacy of weight-loss supplements, such as small sample sizes, short intervention periods, little or no follow-up, and whether the supplement is given in combination with an energy-restricted diet or increased exercise expenditure. There is no strong research evidence indicating that a specific supplement will produce significant weight loss (>2 kg), especially in the long term. Some foods or supplements such as green tea, fiber, and calcium supplements or dairy products may complement a healthy lifestyle to produce small weight losses or prevent weight gain over time. Weight-loss supplements containing metabolic stimulants (e.g., caffeine, ephedra, synephrine) are most likely to produce adverse side effects and should be avoided.

Publication types

  • Review

MeSH terms

  • Body Composition / drug effects*
  • Diet*
  • Dietary Supplements* / adverse effects
  • Humans
  • Obesity / prevention & control*
  • Outcome Assessment, Health Care*
  • Research Design
  • Weight Loss / drug effects*