Here comes weight-loss pseudoscience-often appearing in spam, the Dr. Oz show, or random google search. Weight loss pseudoscience, especially those who claim it’s “easy”, are an American obsession, especially since since the country is experiencing an obesity epidemic. Americans are always seeking easy, simple, but effective ways to lose weight that don’t require them to change any behavior at all. In other words, let us eat our Big Macs and never exercise while taking a miracle pill, while maintaining a perfect Body Mass Index. If that existed, whoever sold it would be richer than Bill Gates.
Recently, two junk science weight-loss treatments have been hitting the public consciousness–raspberry ketones and green coffee beans. Dr. Oz, who despite a solid education in science-based medicine, and has taken to promoting everything from homeopathy to Joe Mercola‘s various lunatic cures, has been pushing both of these weight loss non-working treatments to his audience. Or if you have a bad spam filter, I’m sure you’ve seen the emails promoting these two supplements.
But are they effective? Let’s check.
Let’s start with the raspberry ketones. It is essentially a phenolic compound produced by the raspberry that gives the raspberry’s aroma that we recognize. However, because it is produced in such small amounts by the plant, the supplement industry must synthesized it chemically to manufacture it in sufficient quantities to be sold as a weight loss pill. So it isn’t a natural product by any means.
The belief that these ketones would reduce weight was based on a single study in rats where 2% of the rat’s high fat diet was replaced with these ketones. That would be an impossibly large amount of the ketones in the diet. Other studies have shown no evidence of weight loss in rats even at levels that are equivalent to 200X the amount that a human would consume. And there is not one single clinical trial that has been published showing that raspberry ketones have any benefit in weight loss. Let’s be honest, despite Dr. Oz’s pseudoscientific push, it has no use.
Next up as a weight loss panacea are green coffee beans, which are just unroasted coffee beans. The belief that green coffee beens had an effect on weight loss resulted from a study that touted the “efficacy of green coffee extract in weight loss.” This caused the next big thing in weight loss. However, as with most one-off studies, it’s very easy to criticize. Let’s turn to the good people at Science Based Medicine, who can spot a good medical scam with one eye and both hands tied behind their backs, who take apart the study:
- It only involves 16 patients. A good clinical trial requires numbers that are adequate to gain some level of statistical significance, and 16 isn’t going to cut it. How about several hundred, with adequate controls, and information about any concomitant data that may have an influence over the results.
- “This study was never registered at clinicaltrials.gov. And there’s no evidence provided that a research ethics board ever reviewed the protocol. I find it hard to believe that any investigator would undertake a clinical trial of an unproven supplement without obtaining prior ethics approval – but that seems to be the case.” This is like the real standard for real clinical trials.
- The green coffee study was published in Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy, which does not have an impact factor yet, probably because it’s a new story. Other journals by Dove Press, the publisher of the journal, have impact factors between 1-3, at the very low end of the scale.
- Even though the journal claims to be peer-reviewed, the time period from submission to editorial decision was 12 days which means review was “cursory”. I’ve criticized these types of open-access journals as being of inconsistent quality, and obviously a “clinical trial” that includes only 16 patients.
- None of the authors were clinicians or experts in the field.
- The authors claimed that the study was double blinded, but because of the the way the study was constructed it was not blinded to either the patient or the clinician.
An important point to remember is that this is a primary study, and no one has repeated the evidence as of yet. And a systematic review of the research into green coffee beans and weight loss lead the authors to conclude that “ the studies are all of poor methodological quality. More rigorous trials are needed to assess the usefulness of GCE as a weight loss tool.” And there are still no clinical trials that have been registered to study the effect of green coffee beans on weight loss. So, don’t hold your breath for the “more rigorous trials.”
Weight loss is rather simple. In general, average calories burned has to exceed average calories consumed. Eat less. Burn more. Your choice. If you’re looking for the miracle weight loss, other than the mythical placebo effect (you think it’s going to work so maybe you eat less or walk more, who knows), it’s not going to do anything for you. Walk a couple of miles. Quit eating those potato chips. That’s my expert recommendation!
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- Vinson JA, Burnham BR, Nagendran MV. Randomized, double-blind, placebo-controlled, linear dose, crossover study to evaluate the efficacy and safety of a green coffee bean extract in overweight subjects. Diabetes Metab Syndr Obes. 2012;5:21-7. doi: 10.2147/DMSO.S27665. Epub 2012 Jan 18. PubMed PMID: 22291473; PubMed Central PMCID: PMC3267522.
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