Dietary Supplements for Improving Body Composition and Reducing Body Weight: Where Is the Evidence?

Abstract

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.

Dietary Supplements for Aquatic Sports

“…A recent comprehensive overview of the wide range of supplements promoted for weight loss concluded that there was little evidence of benefit from most of them (Manore, 2012). Many of these products contain stimulants-most commonly caffeine, ephedra, synephrine, and related compounds-as active ingredients and are therefore likely to be associated with some adverse effects, especially when consumed in amounts greater than the recommended dose.…”

Weight loss herbal intervention therapy (W-LHIT) a non-appetite suppressing natural product controls weight and lowers cholesterol and glucose levels in a murine model

“…Notably, this formula does not contain the stimulant Ma Huang ( Ephedra sinica ), which has significant safety concerns when used for weight loss at large doses [7]. We also conducted standard acute and sub-chronic toxicity studies in mice.…”

“…Over the counter dietary supplements are widely used by individuals attempting to lose weight, but evidence supporting their efficacy is lacking. As reviewed by Manore in 2012 [7], most dietary supplements only result in less than 2 kilogram (2-3%) weight loss in adults. Certain imported dietary supplements have been found to be adulterated with prescription drugs, including amphetamines, benzodiazepines, and fluoxetine, which has led to an FDA warning against their use [8].…”

<i>p</i>-Synephrine: A Novel Agonist for Neuromedin U2 Receptor

“…[29][30][31] These products were designed to promote thermogenesis and increase metabolism, suppress appetite, and/or slow the absorption of fats and carbohydrates. [2][3][4] However, due to lack of directly attributable adverse effects to p-synephrine and bitter orange extract, the safety of p-synephrine was frequently questioned, such as the potential cardiovascular hazards (strokes and cardiac arrhythmias). [32][33][34][35] In recent one or two years, Stohs et al specially did some studies on the risk of p-synephrine.…”