For some past research, I once obtained some pure green tea extract that was 98% EGCG, the widely touted “catechin” from green tea, epigallocathechin-gallate, and used it in a few experiments. I was surprised at how reactive it can be. This white to light pink compound can make some very ugly colors. For example, a little EGCG solution mixed with a bit of baking soda and spilled onto a white shirt can slowly go from nearly colorless to yellow or brown and sometimes form an ugly dark green that won’t wash out.
EGCG, like other catechins, has been touted for a variety of health benefits, but if you are taking concentrated green tea extract as a dietary supplement, please be careful and don’t take too much. Not a lot is known about the safe maximum dose for these purified extracts. What causes some humans to become ill from green tea extract is not quite clear, either. Take a look at the BBC story, “The food supplement that ruined my liver,” before you use green tea extract too heavily.
Some Latter-day Saints who choose not to drink green tea (after all, it’s from the same plant whose leaves are further oxidized or fermented to give black tea) may feel they are missing out on the health benefits of the catechins in tea. Good news! Catechins are in many other foods, including chocolate, apples, berries, persimmons, and more. As we read in the book Polyphenols in Human Health and Disease, “Catechin is present in many dietary products, plants, fruits (such as apples, blueberries, gooseberries, grape seeds, kiwi, strawberries), green tea, red wine, beer, cacao liquor, chocolate, cocoa, etc.” You can also find catechins in some beans, sweet potatoes, etc. We can skip the alcohol and the tea and still get all the catechins we might need from a healthy diet rich in fruits with a touch of chocolate every now and then. As for chocolate, science has spoken: “branded chocolates [like Godiva] contain higher levels of catechin and epicatechin” than many others.
I’ve never understood the obsession with dietary supplements, fad diets, etc. Just eat a good variety of fresh food, get lots of exercise, and beyond that don’t worry about it.
— OK
The data that I've seen says you are right, OK. It's often hard to show a benefit to supplements, and sometimes there are harms. A healthy diet with fresh fruits and vegetables makes the most sense. By the way, in spite of many concerns about food and environment in China, our health has been better than ever while here and my wife and I both think it's the diet. A diet rich in basic Chinese food (the kind eaten by regular folks, not the super wealthy), which is a big part of what we eat, is naturally rich in fresh produce without too much meat and with very little sugar. Living here also motivates us to walk a lot, ride our bikes a lot, and we have a decent gym just down the street. China has been great for our health, in spite of some air pollution.
One must wonder, when there is 2% unaccounted for, what solvent(s) were used to get the 98% and whether there is a toxic residual (of about 2%).