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!

Green Tea

I often get asked if coffee is bad. It’s not really a yes or no answer, and I tackled that question a few months ago, here. Some people worry they drink too much coffee, and try incorporating green tea into their diet to get the caffeine without the negative side effects of coffee. Green tea’s health benefits have been talked about for a long time now, and there are even products like green tea ice cream and Starbucks’ green tea latte (which I think is pretty gross because it’s this limey-green color, which just cannot be natural…).

Last week, my parents sent me the Tufts University Health & Nutrition Letter. My aunt Julie gave them a subscription as a gift, because they love reading about health and nutrition (a love I seemed to inherit!). There is an article in there about green tea, and I found it interesting and thought it would be good to reiterate the importance of green tea in the diet.

SO, consider this a refresher/reminder on why we should all be drinking green tea!

The researcher at Tufts who is studying the many health benefits of green tea says we can almost think of green tea as a plant food. Green tea comes from the leaves of the camellia sinesis bush and contains many natural antioxidants. Green tea has a higher level of antioxidants than other teas because of the way it is processed. As we know, the more processed a food, the fewer nutrients there are within that food. Green tea leaves are withered and steamed, and that’s it. Other teas go through further levels of processing, including fermenting, which alters the plant such that some antioxidants are lost.

Traditionally, green tea was used as a stimulant, diuretic and astringent, and was known to protect the heart, regulate blood sugar, improve digestion, treat gas or bloating, and strengthen the mind. Recent studies have shown that people in China and India, who have been using green tea for half a million years, were onto something:

• A 2006 study found that those who drink 5+ cups of green tea per day have a 26% lower risk of death by cardiovascular disease than those who drink 1 or fewer cups per day.

• The polyphenols in green tea may help reduce plaque buildup on teeth and prevent cavities and tooth decay.

• The Cholesterol Treatment Center in New Hampshire conducted a study and found that green tea catechins (antioxidants) may help lower LDL cholesterol and increase vascular function.

• Green tea may inhibit growth of early-stage cancer cells in those who drink at least 2 cups per day.

• Green tea can help with weight loss, particularly abdominal fat. Drinking 2-3 cups per day can lower triglyceride levels and BMI.

• The antioxidants in green tea can combat the growth of viruses and bad bacteria. They also help keep us young by reducing DNA damages associated with aging.

Most of us have tried green tea and many people enjoy it. The hard part, at least for me, is drinking enough of it to reap all of the health benefits listed above. Here are some ideas for ways to incorporate green tea into your diet:

• Brew a big pot of green tea and keep it in a pitcher in your fridge. Add to smoothies in place of juice.

• When you make iced tea this summer, make it half green tea, half regular. The taste won’t be altered much and you’ll get the extra antioxidants.

• Try adding green tea to soups. They usually call for water anyway, so green tea will be an easy substitution.

• One or two days per week, have green tea instead of coffee.

• Add honey, fresh lemon, or ginger to your green tea to make it more enjoyable and contribute to the health benefits.

• Remember in December when I told you about Drazil Foods? Try adding green tea to your kids’ smoothies or fruit juices so they can benefit from the antioxidants too!