Ask Dr. Gourmet

Does caffeinated coffee have more antioxidants than decaffeinated coffee?

1) Are there as many antioxidants in caffeine free instant coffee as in regular? My husband has an enlarged prostate and the doctor told him to avoid caffeine; perhaps that is because caffeine makes one urinate more and not that it is bad for the prostate.

2) Are there more antioxidants in coffee or in caffeine free green tea? You are such a wonderful source of information.

Dr. Gourmet Says...

There's a tremendous amount of research showing the benefits of both coffee and tea. One of my favorites shows that coffee consumption may actually reduce the risk of diabetes. The feeling is that these benefits come from the large amount of antioxidants in coffee.

It appears that it doesn't matter very much whether it is decaffeinated or not. There's not a major difference in the amount of antioxidants in regular or decaffeinated coffee. A group in Italy measured antioxidant activity using a number of tests including the Ferric reducing antioxidant power (FRAP), total radical-trapping antioxidant parameter (TRAP) and Trolox equivalent antioxidant capacity (TEAC). These tests look at how well various chemical changes occur with the interaction of various foods.

For instance, they list the FRAP of espresso at 129 and the decaffeinated version at 93. The roughly 25% reduction with the decaffeinated version applies for the other tests as well. The researchers looked at green tea and found a FRAP of 18 with black tea coming in at 10. As you can see, both contain fewer antioxidants, but in my opinion this is not a major difference.

Your husband's doctor is correct. It appears that caffeine does cause an increase in symptoms for men with enlarged prostate, and decaffeinated coffee is a great way to get a big dose of antioxidants without a big increase in symptoms. Great news for those of us who love coffee.

Thanks for writing.

Timothy S. Harlan, MD, FACP
Dr. Gourmet