A review of many clinical studies found slightly increased mortality (i.e., more people died during studies) associated with the use of supplements containing beta-carotene and possibly vitamin E and higher doses of vitamin A. Similarly, a study found that high levels of vitamin E and vitamin A in the blood are associated with a greater mortality risk than moderate levels. Get the details in the Full Answer >>

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October 5, 2014

A popular figure in the world of supplements sells (quite expensive) multivitamin-mineral capsules for daily use that contain no folic acid. In his view only dietary folate from vegetables is free from potentially harmful effects. (In addition the multis have no beta-carotene or vitamins A and E because of purported adverse effects.) However, my last blood work while taking these showed high homocysteine levels (first time this has occurred). This can't be good. Question: how do I get enough folate when obviously my veggie consumption, which is about all I can eat, isn't nearly enough? Is folic acid that harmful?
October 9, 2014

Hi Ann - Thank you for your question. We've answered it here:

Diane 17497
January 27, 2019

Does astaxathin fall into this category of antioxidants to be cautious with?
January 28, 2019

Hi Diane - Please see the "Concerns and Cautions" section of the Astaxanthin Supplements Review for information about this:

January 27, 2019

I was treated for early stage breast cancer last spring at City of Hope. Fortunately I did not need chemo, but did have 6 weeks of daily radiation. The radiation oncologist was adamant that I stop all supplements for the reasons you stated in your article. Of course, I listened to him and complied. He also mentioned that alpha lipoic acid was one of the most suspicious when it came to radiation and protecting the cancer cells. I was a low risk patient for breast cancer, but spent decades taking supplements....and now wonder with recent studies pointing the finger at supplementation in pill form whether or not I reached some tipping point in my body where they played a role in the advent of the cancer.

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