New Study on Antioxidants

[Guest guest]

day's Question

What do you think of the new study showing that antioxidants don't

cut the risk of heart disease and that beta-carotene may even

increase the risk? I understand that the researchers recommended

discontinuing clinical trials using beta-carotene supplements.

 

-- Terry

 

Today's Answer

(Published 07/14/2003)

In this report from the Cleveland Clinic Foundation, researchers

analyzed data from 15 different studies of vitamin E and beta-

carotene. Their conclusions and recommendations were published in

the June 14th issue of The Lancet. The researchers concluded that

use of beta-carotene and vitamin A supplements (a beta-carotene

metabolite) should be discouraged, that clinical studies using these

antioxidants should be discontinued, and that vitamin E should be

excluded from trials of patients at high risk of coronary artery

disease.

 

These recommendations might appear alarming until you consider that

the 15 studies analyzed took place among people already suffering

from serious diseases or considered at high risk and that the

results of the studies reviewed already were known.

 

Among the eight beta-carotene studies analyzed were two showing that

the supplements didn't help prevent lung cancer among smokers. In

fact, the harmful effects attributed to beta-carotene in the

Cleveland Clinic analysis largely stemmed from these two studies,

conducted among more than 43,000 smokers.

 

In the seven vitamin E studies reviewed, the supplement reportedly

didn't reduce the risk of stroke or of dying of heart disease among

people who already were at high risk or ill.

 

Not surprisingly, the recommendations are controversial considering

indications that vitamin E may still prove to help prevent heart

disease among healthy people,

 

and the lack of evidence showing that beta-carotene supplements are

harmful to non-smokers.

 

The researchers also failed to consider the forms of carotenoids and

vitamin E used in the studies they analyzed.

 

I stopped recommending isolated beta-carotene supplements years ago

and urge people to get the antioxidants they need from fruits and

vegetables. Peaches, melons, mangoes, sweet potatoes, squash,

pumpkins, tomatoes and dark leafy greens are good sources of beta-

carotene and related carotenoids.

 

If you want to supplement your diet, take a product that provides

as many members of this family of protective pigments as possible:

alpha-carotene, lutein, zeaxanthin, lycopene, etc.

 

As for vitamin E, most studies use *synthetic* alpha-tocopherol. I

recommend using natural vitamin E supplements that provide all four

tocopherols and all four tocotrienols.

 

Dr. Andrew Weil