In an episode of "The Dr. Oz Show," Mehmet Oz, the Oprah of medicine, told viewers that raspberry ketone was "the No.1 miracle in a bottle to burn your fat."

And just like that, raspberry ketone became the next darling of the miracle-seeking set, flying off the shelves of health food stores and becoming the latest shining hope for all seeking a magic bullet for weight loss.

Raspberry ketone is the aromatic compound that gives berries their distinctive smell; it is used as flavor and fragrance in both food and cosmetics. It is chemically similar to capsaicin, the heat compound that gives chile peppers their fire. It comes in supplement form with a recommended dose of 100 milligrams per day. To recieve the same benefit from the whole fruit, you'd have to eat a prohibitive 90 pounds of raspberries. 

A number of studies from Asia report that raspberry ketone might help burn fat, and the purported benefits are also intriguing: lower cholesterol, increased sensitivity to insulin and weight loss.

However, all the research has been performed on small scampering creatures, not humans. And experts point out that many weight-loss supplements that seem to have potential in laboratory rodents fail to have promise in the real world. Part of that is because the tests are performed on overweight and unstimulated animals who are housed under standard laboratory conditions. They're not the best control subjects.

So it is a bit of a mystery to read on the Dr. Oz website that “raspberry ketone causes the fat within your cells to get broken up more effectively, helping your body burn fat faster.” It’s not clear how that claim can be made given that no research has been performed on human subjects. That said, some of the science does look promising; it just needs further validation before miracle status should be granted.

According to Dr. Oz, researchers have observed that, compared to controls, raspberry ketone decreased the amount of fat in the liver and abdominal fat tissues of mice. It also significantly increased the decomposition of fat in some rat fat cells. Researchers also tested in vitro fat cells with raspberry ketone and found that they showed greater evidence of breakdown when compared to controls.

The TV doc has also shown a lot of enthusiasm about adiponectin, a protein used by the body to regulate metabolism. He notes that higher levels are associated with fewer fat stores. Scientists studied the effects of raspberry ketone on in vitro fat cells and observed a higher secretion of adiponectin when compared to controls.

But what does that have to do with dropping a dress size?

Dr. Oz’s televised segment displayed before-and-after pictures of women who had lost substantial amounts of weight while taking raspberry ketone supplements, but, not surprisingly, Oz noted that the women had consumed less calories and exercised.

As noted on the Oz website, “raspberry ketone can help in your weight-loss efforts, especially when paired with regular exercise and a well-balanced diet of healthy and whole foods.” Where’s the miracle in that?

Have you tried raspberry ketone? Did you find that it helped?

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