Herbal supplements don't work for weight loss, new research shows.
In the first global review of herbal weight-loss supplements in almost two decades, investigators found there was insufficient evidence to recommend any of these "medicines" for this purpose.
"There was no evidence to suggest people should be taking herbal medicines for [clinically meaningful] weight loss," study investigators Erica Bessel, MND, and senior author Nicholas R. Fuller, PhD, both from the University of Sydney, Australia, told Medscape Medical News via email.
The study findings suggest "healthcare practitioners should continually prompt their patients regarding any over-the-counter weight loss medications they are taking, so they can steer them towards evidence-based care," they added.
Overweight and obesity have reached epidemic proportions worldwide, with the global prevalence doubling since 1980.
For individuals who are unable to lose a satisfactory amount of weight with lifestyle interventions there are currently five prescription weight-loss drugs approved by the US Food and Drug Administration (FDA), three of which have also been approved by the European Medicines Agency and Australian Therapeutic Goods Administration.
The addition of these approved agents to lifestyle interventions increases weight loss but some patients avoid or stop taking these drugs because of side effects and costs.
Many individuals turn to over-the-counter supplements, which are cheaper, easier to access, and may have fewer side effects, the investigators note.
A recent study reported that 16.1% of individuals in the United States who were trying to lose weight had used a weight-loss supplement in the past year.
However, despite the large number of herbal weight loss supplements on the market, few are supported by robust scientific safety and efficacy data.
Not Clinically Significant
To update the available evidence of these supplements, the investigators conducted a systematic review and meta-analysis of herbal medicine for weight loss.
The study included data from 54 randomized placebo-controlled trials of herbal weight-loss medicines conducted in 4331 overweight or obese adults in countries around the world that lasted 12 weeks or less.
Common herbal supplements included in the studies were:
Green tea (12 studies)
Malabar tamarind (11 studies)
White kidney bean (seven studies)
Ephedra (five studies)
African mango (three studies)
Yerba mate (three studies)
Veld grape (two studies)
Licorice (two studies)
Mangosteen (two studies)
Miscellaneous herbal medicines (17 studies)
The study was published online February 15 in Diabetes, Obesity & Metabolism.