Monday 10th December 2018,

Raspberry Ketone – Slimming Sensation?

Raspberry Ketone – Slimming Sensation?

It seems yet another easy way out of obesity has surfaced in the form of ‘Raspberry Ketone’ as promoted by one Dr. Mehmet Oz, a television personality and former cardiothoracic surgeon.

Before we talk about Raspberry Ketone, let’s run through a few of the other things that Dr. Oz is known to have recommended: Homeopathy (no scientific proof), energy healing (no scientific proof), Reiki (no scientific proof) and Transcendental Meditation (no scientific proof). Can you see a pattern?  However, just because some of his favourite treatments lack research-based credibility, it would be unfair to assume that this one does too, since there is at least a teeny weeny bit of scientific research behind the Raspberry Ketone idea.

Although it is also found in cranberries and blackberry’s as well, Raspberry Ketone (RK) is essentially a natural organic compound found in its largest quantities in raspberries. It is chemically extracted and converted into capsule form. A whole kilo of raspberries gets you no more than 4 milligrams of RK.

A 2005 study in Japan on mice showed that when fed on a high fat diet supplemented with RK, the little squeakers lost a decent amount of weight, or at least didn’t put on the weight that they ought to have done after weeks of scoffing. As that’s about it for the ‘research’ part; we can fast forward a few years to where £20 will get you 60 capsules, or one month’s supply – despite no clinical trials being conducted on humans.

Some of the RK ads on the web even carry a photo of the reassuring yet now seemingly obligatory ‘medical looking guy’ wearing a white coat with a stethoscope round his neck, plus the internationally recognised sign of a high IQ – a pair of spectacles. These supplement manufacturers are a lot cleverer than us, but not in the way most of us think!

The supposed benefits of Raspberry Ketone appear to hinge on the belief that it encourages the body to produce more adiponectin, a hormone which is known to have an inverse relationship with body fat percentage in humans. In other words, obese people have very little adiponectin, whilst slim people have it in abundance   However, slim people also have more pairs of skinny jeans, but does an obese person lose weight just because they snap up a pair? Correlation does not imply causation.

Going back to our Japanese mice, it appears that they were fed Raspberry Ketone in quantities equivalent of up to 2% of their bodyweight. Given that each capsule of RK contains just 100 mg, then to replicate the same effects our mice ‘enjoyed’, an 80 kg person would have to consume 1.6 kg of Raspberry Ketone – that’s 16,000 tablets per day. Compare this to the recommended dosage of just 1 to 2 tablets per day.

So what about the reported success stories of weight loss in humans? The web is crawling with stories of people who have apparently lost up to 7 lbs in a week, but since the general consensus is that the first week produces the best results, could it be that this weight loss is mainly water, with Raspberry Ketone acting as a diuretic? RK is also being sold as a supplement to a low calorie diet, so maybe it’s the lack of calories that’s delivering the results while the supplement delivers the cash for the supplement companies.

It’s hard to know for sure as without the right clinical trials we can’t adequately eliminate the possibility that such stories are not a result of additional factors or even a placebo-induced change in diet or exercise. Perhaps some of the success stories have even simply been invented or exaggerated. People telling lies to make money? That could catch on.

Even if we assume that the reported Raspberry Ketone-related weight loss is bona fide, what we absolutely cannot say for certain what the longer term effects of RK might be. It’s already suspected to weaken androgen receptors which in turn are bad news for the all-important muscle building hormone testosterone. Less testosterone can mean a reduced ability to build or maintain muscle – crucial for maintaining longer term fat loss.

Many of the ads for RK make a big thing about how it’s from ‘natural’ ingredients and therefore cannot possibly be dangerous. Let’s be clear – all foods start life as natural ingredients, but many undergo various changes to make them what we end up eating. Even the cheese in your McDonald’s cheeseburger starts life as a collection of natural ingredients. That’s why they call it ‘processed cheese’. RK is prepared using ‘crossed aldol-catalytic hydrogenation’. Not so natural as the simple raspberry it started out as.

Like the benefits of Raspberry Ketone, we can’t say for sure what the side effects might be without the proper human clinical trials which don’t appear to be on the horizon. Given the clamour for RK one would think that there’d be no shortage of volunteers to sign up for a proper trial where they can try it or a placebo, for free, should one of the manufacturers to sponsor a trial. However, when you already have a product that has enough pseudo-science behind it and enough people believing in it to make you a ton of cash, why take the risk?

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About The Author

Paul has been a Personal Trainer since 1997 and currently freelances at The Capel Gym in Five Oak Green, Kent, as well as Hilden Park in Hildenborough.

  • This is so typical of the health and wellness industry. The business of pedaling snake oil is alive and well, for what it’s worth.

    There’s a great section in the book “Social Media is Bullshit” that outlines the exact process, but it sure seems to move a lot faster when people’s health and wellness are involved.

    Thanks for clearing the air on this – yet another reason UsFitties is my favorite wellness blog.

  • Very interesting.. especially since I LOVE raspberries… one of my favs outside of pineapples. But could a capsule be expensive since raspberries themselves are. In either case, I also agree with Nick.. you all provide some excellent info.. thx