A few days ago I noticed an advertisement for a new “weight loss supplement”: raspberry 
ketones. This one has apparently been endorsed by Dr. Oz and is being advertised all over the internet.
I’ll tell you what the research really says, but let’s first talk about fat loss pills/supplements in general. There are basically three ways a drug or chemical can aid in fat loss:
- 1. Decrease/suppress appetite
- 2. Prevent absorption of calories
- 3. Aid in lipolysis (the breakdown of fat)
Is there any evidence this supplement does any of these three things? One study 
demonstrated raspberry ketones had a protective effect on the health of rats that were fed a high fat diet.1 Yes–all this hype over studies on rodents. I’m not aware of any research clearly demonstrating this supplement’s effectiveness for humans in losing weight.
I wish I could say I was surprised, but quoting inappropriate research (like animal studies) has been a favorite tactic of supplement manufacturers for a long time.
Raspberry ketones could be be a good source of antioxidants (assuming they are processed correctly). 2 But that is not the way they are being marketed–at least not in the advertisements I am seeing.
My Recommendation:
I wouldn’t spend any money on this kind of supplement. Look into a good diet and exercise program if you are really wanting to lose weight.
References:
1. Life Sci. 2005 May 27;77(2):194-204. Epub 2005 Feb 25. Anti-obese action of raspberry ketone.
2. J Agric Food Chem. 2011 Dec 15. [Epub ahead of print] Comparison of Flavonoid Composition of Red Raspberries ( Rubus idaeus L.) Grown in the Southern United States.
