Green Tea: Decaf or Caffeinated?

Dear PWN,

I have a green tea question for you. I've been drinking green (iced) tea all summer. I just went back and re-read your entry on green tea (read it here). Health benefit-wise, is there any issue with drinking decaf green tea as opposed to regular green tea?

This is a great question, and I had to do some research to find the answer. My gut told me that since green tea is naturally caffeinated, it would have to go through some level of processing to become decaffeinated and therefore the nutrient content and health benefits could be compromised. I was partially correct. Here’s what I found:

One green tea bag contains about 20 mg of caffeine on average. If the bag is reused for a second cup of tea, the caffeine content decreases. 20 mg is not much – for the sake of comparison, one cup of coffee (5-oz cup, not a “small” or “tall”) contains about 80 mg of caffeine. So, the caffeine content in green tea is naturally less than that of coffee or even soda. All caffeinated tea comes from the same plant, the Camellia sinesis, which naturally contains caffeine. Any herbs that are added to teas to create different herbal teas do not contain caffeine, which is why herbal teas such as peppermint or chamomile tea are very low in caffeine.

Some studies show that decaffeinated green tea may have fewer antioxidants than caffeinated green tea. The caffeine must be removed through one of a few different processes, and depending on the process used, some of the antioxidants are also lost. Sometimes the decaffeination process will be noted on the tea label. The “CO2” process tends to retain many of the antioxidants, whereas the “ethylene acetate” process kills off 70% of the antioxidants and some flavor as well. Apparently there is one process in which 95% of the antioxidants are retained in the green tea. If the label does not indicate which decaffeination process is used, feel free to call the company and ask about this. I always encourage people to be proactive if they have a question about something they are purchasing as it relates to their health!

Decaffeinated green tea will still contain some valuable antioxidants and if you are sensitive to caffeine, it is still beneficial to include this tea in your diet as much as possible. Too much caffeine can be harmful to health, although the levels in green tea are fairly low and a few glasses per day won’t hurt a healthy person. If you are drinking multiple cups of tea per day, it may be wise to reuse the tea bag once or twice. This will not only allow you to get a good combination of high antioxidants and low caffeine levels, but it will also save you money.

Thanks for the great question! And to the others who have sent me questions this week, they are on my list so check back over the next week or two for your answers!