Is Dr. Oz more showman than doctor? His theatrical endorsement of dubious weight loss products points to the former. On his show this week, in a 75-second segment, he introduced a ‘revolutionary metabolism booster that you’ve never heard of’: raspberry ketones. While displaying a generic purple jar of capsules, Dr. Oz said, “I have vetted these; I’ve looked at them carefully; I am absolutely enamored. I know they work.” His segment assistant Lisa Lynn, a supplement-selling personal trainer, was by his side, along with a morbidly obese woman who had “tried everything.” Was Dr. Oz laying it on thick for a questionable product? No, not when you consider Dr. Oz is on TV.
Raspberry ketones are compounds that give red raspberries their aroma. In the US, they are used primarily in the food flavor industry. In Japan, however, raspberry ketone capsules are used as a weight loss supplement. Raspberry ketones are not to be confused with blood ketones produced in diabetes and on very low carbohydrate diets.
The hypothesis is that raspberries ketones affect biological activities that alter lipid metabolism. That fat-blasting claim rests on two small mice studies that show when mice are fed a high-fat diet supplemented with raspberry ketones they gain less body fat than expected. But be clear: raspberry ketones have not been studied in humans and they have not been proven to work. To be fair, Dr. Oz said, “There have not been a lot of human studies, but animal studies are favorable.” Somehow, for me, that got lost in the hype. (more…)
