Chinese Rhubarb

The Nonexistent Evidence for Herbal Weight Loss

The strongest defense of a scammer often comes from the people who fall for the scam. For inexplicable reasons, people sometimes like sweet little lies and insist that liars are dispensing truth. So it is with herbal supplements for weight loss. People desperate for help in overcoming issues with obesity latch onto these scams. They spend more than five billion dollars annually on such scams in the U.S. alone. But a new systematic review and meta-analysis confirms what we’ve known for all along. These products simply don’t work.

The study appears in Diabetes, Obesity, and Metabolism.

“Insufficient Evidence”

Alison Maunder et al found 54 randomized controlled studies of herbal medicines for weight loss. These studies included trial of nine different active ingredients. Among those nine ingredients, only one had any effect. But the effect of that ingredient – Phaseolus vulgaris – was clinically insignificant. Subjects lost a mean of less than four pounds. We often see our own weight vary randomly by two or three pounds from day to day. It’s normal fluctuation, hardly a weight loss miracle.

It’s worth noting that these studies involved more than 4,000 subjects altogether. Though the studies had “generally poor methodological quality,” one might have expected a few positive results. But that was not the case.

Evidence Not Necessary

The problem with dietary supplements is that people are often buying into fiction when they seek a therapeutic effect. No evidence of effectiveness is necessary to sell them. Senior author Nick Fuller explains:

The problem with supplements is that unlike pharmaceutical drugs, clinical evidence is not required before they are made available to the public in supermarkets or chemists.

This finding suggests there is insufficient evidence to recommend any of these herbal medicines for the treatment of weight loss. Furthermore, many studies had poor research methods or reporting and even though most supplements appear safe for short-term consumption, they are expensive and are not going to provide a weight loss that is clinically meaningful,

Just to be clear, we are not talking here about real nutritional supplements – like the vitamins and minerals that bariatric surgery patients actually need to take. We’re talking about herbal weight loss products.

And the people selling them are simply selling sweet little lies – and making money from people desperate to believe them.

Click here for the study and here for further perspective.

Chinese Rhubarb, photograph © Eric Huybrechts / flickr

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February 18, 2020