Friday, October 14, 2011

Antioxidants: Tea vs. Vitamins A, C, and E

This post is about the relationship between tea, antioxidants, and several different classes of antioxidants, including essential vitamin antioxidants (including Vitamins A, C, and E), synthetic antioxidants, and naturally-occurring antioxidants such as catechins and anthocyanins. I wrote about antioxidants last November, but this post goes into more depth.

Pictured here is one of my favorite fruits, a blood orange:

A blood orange is an interesting variety of orange that has a deep reddish color. The red pigment is due to the presence of anthocyanins, a class of natural pigments which are known to work as antioxidants. Another red-pigmented orange variety, the Cara cara orange, or red navel orange, is also pigmented red, but due to a different pigment, lycopene, the pigment giving tomatoes their characteristic orange-red color. I chose an orange because oranges have a reputation for being very high in Vitamin C. Vitamin C is also an antioxidant.

Anthocyanins also occur in high concentrations in certain varieties of tea plant. One particularly pronounced example of this is purple tea, which is a varietal of tea plant with dark purple leaves, loaded with anthocyanins. This variety was developed in Kenya. I recently tried purple tea for the first time, and I hope to write more about it in future posts.

Antioxidants in Tea:

One of the most popular topics when it comes to tea and health is that of antioxidants. Unfortunately, "antioxidants" have become a bit of a buzzword, and in some cases, a marketing scheme or even scam used to sell tea, or worse, sell herbal supplement products containing tea.

It is pretty well-established scientific fact tea is rich in antioxidants. If you want to read in more depth about these chemicals, there's a ton of info on RateTea's article on antioxidants in tea. What's less clear is the degree to which these antioxidants are actually beneficial to health. As strange as this may sound, although there's a fair amount of evidence that tea is good for your health, there's little to no evidence that the health benefits of tea can be attributed to the antioxidant activity of chemicals in the tea. The article explains more.

Essential Antioxidant Vitamins vs. Other Antioxidants:

Many people are surprised to learn that a number of essential vitamins, including Vitamin A, Vitamin C, and Vitamin C, are antioxidants. Perhaps more shocking to health nuts is the realization that the synthetic preservatives BHA (Butylated hydroxyanisole) and BHT (Butylated hydroxytoluene) are also antioxidants. BHA and BHT are both controversial food additives, and both show some evidence of having harmful effects on health, although the research on this topic is inconclusive. The point is, antioxidants are not necessarily beneficial, and can even be harmful.

Essential Vitamins, on the other hand, are very different beasts. Vitamins A, C, and E are all antioxidants. Although each of these vitamins can be problematic in extremely high doses under certain conditions (one form of Vitamin A, retinol, can be harmful in high doses, and others, such as beta-carotein, can turn your skin orange) they are generally quite safe. There is a lot of research suggesting that most people in the U.S. consume far too little Vitamin C, although this is a matter of controversy. Wikipedia has some good sources on this controversy on their section on Vitamin C's Daily Requirements.

The catechins, the antioxidants of green tea, and the theaflavins and thearubigins (together called tannins), are not essential nutrients. They may be beneficial to health, but they are certainly not necessary, and they do have some downsides (such as inhibiting iron absorption).

Tea or fresh fruits and vegetables?

As wonderful as tea is, it is not necessary to human health, nor is caffeine, nor is theanine, an amino acid derivative found in high concentrations in tea.

Fresh fruits and vegetables, for the most part (with a few exceptions such as certain Inuit diets), are necessary for optimal health. If you want antioxidants, eat a diversity of fresh fruits and vegetables...they're loaded with vitamin A, C, and E, nature's antioxidants. Drink tea if you like the taste, and the way it makes you feel.

What do you think?

I'm much of the information in this post is new, unfamiliar, or surprising to you, and how much of it is old stuff that you already know inside and out?

1 comment:

  1. Much of the information you shared in this post was review for me (in a good way), but I also learned some new tidbits too! When I first started my tea blog last year, I did some extensive research on the health benefits of green tea because it was such a hot topic.
    My conclusion then and still is: Tea is not a magic potion (except for Ozzy Osbourne before a gig). Tea may have some positive health benefits, but more research needs to be done for conclusive evidence. In fact, for those with caffeine sensitivity or tendency for anemia, tea may not be the healthiest beverage choice.
    Oh, and I so agree with your comment about the health benefits of eating fruits and vegetables! Now, that’s a health fact folks can really sink their teeth into!