The Truth on Raspberry Ketones

Earlier in 2012, Dr. Oz did a feature on the fat-burning magic of raspberry ketones, a dietary supplement you can easily find in grocery stores, GNC stores and supermarkets. Lisa Lynn, a “weight loss expert” and personal trainer, was on the episode with Dr. Oz explaining to viewers that raspberry ketones have the ability to burn fat easier—another weight loss breakthrough.  After this particular show, stores had trouble keeping the supplements in stock as customers were purchasing these pills as if they were the answer to weight loss prayers. If you have never seen or heard of these supplements before you may start to notice them during the beginning months of 2013 considering New Year’s resolutions for many are underway. 

What are raspberry ketones? Raspberry ketones are a major compound naturally found in red raspberries that give off raspberry’s aroma—they have the chemical structure similar to capsaicin and synephrine (a compound that made bitter orange popular as a weight loss agent—proven to have insignificant weight loss effects).  Raspberry ketones have actually been used in our food system as a flavoring agent and food coloring component; however, it is extremely expensive to extract raspberry ketone from raspberries so what is available in stores is actually made in a laboratory.  This means that even if it is sold as “natural” it is most likely made in lab. 



Big Takeaways:

1.  This is not a miracle cure.  The only small scientific studies done using raspberry ketones have been on mice—not humans.  It has NOT been shown to have any significant increases in resting metabolism even though it is advertised to increase the metabolism by increasing the release of one of our flight-or-flight hormones (norepinephrine) as well as affecting adiponectin (a protein) found on fat cells which decreases glucose levels.


2. Negative side effects have been noted.  Heart palpitations, rise in blood pressure, tremors, and jitteriness are potential side effects due to raspberry ketone’s similar structure to synephrine.  Also, a lot of raspberry ketone supplements contain more than just that—green tea extract, hoodia, caffeine, capsaicin, etc.   


3. Read the Bottle:  “This information has not been evaluated by the Food and Drug Administration, nor has it gone through the rigorous double-blind studies required before a particular product can be deemed truly beneficial or potentially dangerous and prescribed in the treatment of any condition or disease.” U.S. Food and Drug Administration


4. Eat Raspberries.  I know that has to sound very exciting and enticing J  1 cup of raspberries contains ~60 calories and 8 gm of fiber—you also benefit from the vitamin C, vitamin K, folate, magnesium, anthocyanins, ellagic acid, and more disease fighting properties.