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Herbalife may not be a Ponzi scheme. But its science is definitely garbage

Bill Ackman
Bill Ackman
Bill Ackman
Stephen Lovekin/Getty Images

Hedge fund billionaire Bill Ackman has spent $50-million trying to demonstrate that Herbalife’s business model is nothing more than an exploitative pyramid scheme.

The company, which distributes mostly nutrition and weight management products, denies this allegation, and the investor’s attempts to squash them only boosted the price of their shares.

Ackman might be more successful if he considered taking on Herbalife’s science.

Bill Ackman's Attacks on Herbalife in 90 Seconds by Bloomberg News

On the Herbalife website, there's a section dedicated to "science videos," where various company stakeholders boast that they "guarantee the very best science" behind their products, which are all "science proven."

Dig a little deeper, however, and it seems the evidentiary underpinnings of Herbalife’s wares boil down to only four very weak studies that can barely be called science, let alone the “very best science.” If this is Herbalife’s prime research and development, then the company’s science is definitely garbage and customers should question the health claims on its products.

A look at Herbalife’s clinical trials

On a dedicated science website, Herbalife cites four clinical trials to prove the safety and effectiveness of its products:

1) The first clinical study compares weight and fat loss in two groups of obese men and women: the first went on a diet involving protein enriched Herbalife meal-replacement shakes; the second dieted with a standard Herbalife shake. While the study shows that both groups lost a few kilograms during the trial, and the protein group didn't fare any better than the other, there are several problems with the research.

First, the Herbalife website states that the study lasted for "over a one-year period;" a closer look at the actual paper reveals that the trial only ran for 12 weeks.

"Any diet study that runs for less than a year or two is worthless," said Dr. Yoni Freedhoff, an obesity specialist and author of The Diet Fix: Why Diets Fail and How to Make Yours Work. Unless people plan to drink two shakes a day for the rest of their lives, he added, this kind of plan is just not going to work in the long term. "I can put someone on a short-term marshmallow diet and they'll lose weight if they consume fewer calories."

Second, the study wasn’t actually designed to look at how Herbalife diet products compare to other weight-loss aids or even other types of diets. It only compares Herbalife products to each other. It would have been more scientific to test whether Herbalife meal replacements fare better than, say, a regular low calorie diet, or whether their shakes help people lose more weight than other meal replacement brands.

2) The second clinical study cited was never even published. Again, if Herbalife is going to claim scientific rigor, it should at least bother to publish all the studies it uses as evidence of "research and development" to see if they pass peer scrutiny.

3) The third study cited also compared the impact of two kinds of Herbalife meal replacement diets on weight and fat loss. Once again, this study only looked at whether a protein-enhanced shake helped people lose more weight than a regular shake. Again, the trial only ran for 12 weeks, and involved 75 obese participants.

Researchers found that both groups lost about the same amount of weight (5 kg). Naturally, subjecting obese people to 1,500-calorie diets that involve one real meal is not scientific evidence for Herbalife’s magic; it just demonstrates that severe calorie restriction for a few weeks will result in some unsustainable weight loss.

4) The final trial on the site focused on Niteworks, a Herbalife powder mix. This research looked at whether the so-called performance enhancer had any impact on the exercise potential of 16 cyclists.

The men on Niteworks supposedly increased their aerobic performance, but this study had problems too: It was tiny, involving only 16 people. They were all elderly, male cyclists—not exactly a representative sample—and it ran for just three weeks. What’s more, the study was funded by Herbalife, not an independent research group, ringing conflict of interest alarm bells.

A missing study

One study, published in the Journal of Hepatology, was not highlighted on the Herbalife website: Researchers in Europe found Herbalife products were linked to ten cases of liver damage. The authors concluded: “Herbalife products are widely available globally. Therefore, it is these authors’ view that closer monitoring of patients taking weight-loss herbal supplements as well as tighter regulation from government drug agencies is warranted.”

Bottom line

If Herbalife wants to make claims to science, it should fund long-term trials comparing its products against other brands instead of short-term studies that mostly compare its own products to one another.

Dr. Freedhoff summed up the problems with the research quite nicely: “It’s a shame we see products being sold on the back of studies that last for less time than many items in my refrigerator.”

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