Ever since Dr. Oz, of Oprah Winfrey and the Doctor Oz Show fame, claimed that raspberry ketone is a "miracle fat burner" the supplement has practically been flying off shelves. Unfortunately he failed to mention some important details.
What Is Raspberry Ketone?
Raspberry ketone (not to be confused with the ketones produced when doing a diet) is the primary organic compound responsible for the aroma of red raspberries. It can be extracted from those and deliver a fruity smell to products it is then put into, which is widely made use of in food and cosmetics.
However, because raspberry ketone naturally occurs only in very limited quantities, for industrial uses it is normally produced with the help of a rather complicated chemical process, and not extracted from its natural source.
Raspberry Ketone And Weight Loss
You now might wonder where the heck the weight loss comes in that Dr. Oz claims raspberry ketone provides. We find it in the form of a small study done on mice (PDF), who were fed a high fat diet and unknown amounts of raspberry ketone to go along with it: they gained less weight than expected. While this sounds promising, there are two important points to consider:
- The effect so far wasn't replicated in humans
- Another study found no effect on mice at daily dosages less than 200 times more what the average human consumes.
The first study never states how much raspberry ketone in milligrams the mice actually were fed; we only get the mention that it was 0.5, 1 or 2 percent of the food they were provided with. The second study gives us some numbers to play around with and, according to those, it takes 100 mg per kg / body weight of mice to have an effect on them. Which means it takes at least 2.2 mg of daily raspberry ketone to have any effect at all on a mouse that weighs 22 g (1 kg = 1,000 g; 1,000 / 22 = 45; 100 mg / 45 = 2.2 mg).
Now, if we do like Dr. Oz did (see below) and extrapolate mouse data on humans, we can go further: if the average mouse weighs about 22 grams and needs 2.2 mg for an effect of raspberry ketone, then to have an effect on a 75 kg (165 lbs) human, we'd need 3,409 times as much raspberry ketone as for the mouse (1 kg = 1,000 g; 75,000 g / 22 g = 3,409). Per day that would be 7,499 mg or 7.5 g (2.2 mg * 3,409; 1 g = 1000 mg).
7,499 mg or 100 mg?
Yet when on his show television Dr. Oz recommended raspberry ketone as a weight loss supplement, he gave his audience a number that was much lower. You can find the clip on his website, with the following claim right below it:
In order to get enough ketone to have an effect on the way your body burns its excess fat, you would need to consume 90 pounds of raspberries! But, just 100mg of the supplement per day is enough to get your body burning fat the way you want it to.
In order to get enough? I'd like to see the reasoning behind the amount he states. Based on the published data, the 100 mg he recommends would most likely only produce an effect in a mouse, while we still have no idea if raspberry ketone has any weight loss effect on humans at all. Not to mention that nobody, including Dr. Oz, knows if regularly gulping down amounts that could have an effect really are safe for humans.
Integrity And Responsibility
I really shouldn't be surprised about this anymore, as the good doctor was already involved in the acai berry craze a couple of years ago, not to mention his other activities that leave question marks. But I still feel that a trained doctor, especially one with this much influence, should adhere to a higher personal standard of responsibility.
Especially if it is a standard he, as a matter of fact, does claim for himself. When he filed a suit against the above 40 or so acai berry marketers unlawfully using his name and image, he told ABC News that people are "often duped into paying more than they should" for "pills that don't really have what's promised in them".
When I looked, the average bottle of raspberry ketone supplement costs $20 to $60. Perhaps it's just me and my personal idea of integrity, but had I uttered the above words and then endorsed something this expensive despite so little factual backing, I couldn't go to bed at night with a clear conscience.