More Evidence for Antioxidant Supplements to Cause Harm

A number of studies show that general antioxidant supplementation interferes with beneficial processes, and is thus harmful to long term health. This post references some of the more recent research on this topic:

You may remember a study that suggested that antioxidant supplement actually negated the effects of exercise in muscle tissue. (The reactive oxygen species generated are apparently being used by the cells as a signaling mechanism, one that you don't necessarily want to turn off). That was followed by another paper that showed that cells that should be undergoing apoptosis (programmed cell death) could be kept alive by antioxidant treatment. Some might read that and not realize what a bad idea that is - having cells that ignore apoptosis signals is believed to be a common feature in carcinogenesis, and it's not something that you want to promote lightly.

Here are two recent publications that back up these conclusions. The BBC reports on this paper from the Journal of Physiology. It looks like a well-run trial demonstrating that antioxidant therapy (Vitamin C and Vitamin E) does indeed keep muscles from showing adaptation to endurance training. The vitamin-supplemented group reached the same performance levels as the placebo group over the 11-week program, but on a cellular level, they did not show the (beneficial) changes in mitochondria, etc.

Then there's this report in The Scientist, covering this paper in Science Translational Medicine. The title says it all: "Antioxidants Accelerate Lung Cancer Progression in Mice". In this case, it looks like reactive oxygen species should normally be activating p53, but taking antioxidants disrupts this signaling and allows early-stage tumor cells (before their p53 mutates) to grow much more quickly.

This is all rather frustrating when you consider the nonstop advertising for antioxidant supplements and foods, especially for any role in preventing cancer. It looks more and more as if high levels of extra antioxidants [at] the very least help along any cancerous cells that might arise on their own. Evidence for this has been piling up for years now from multiple sources, but if you wander through a grocery or drug store, you'd never have the faintest idea that there could be anything wrong with scarfing up all the antioxidants you possibly can.



Huge load of cherry picking.

Posted by: majkinetor at February 6th, 2014 8:09 AM


Do you believe the issue is antioxidants in their pill-form, or do you believe this extend to whole-foods rich in antioxidants?

Posted by: Cosmicalstorm at February 6th, 2014 11:28 AM

I think it depends on the antioxidant, from what I hear some can turn pro-oxidant, but there are some exhibiting anticancer activity in addition to their antioxidant activity.

Also while reasonable dosing seems to be more moderate for humans, substances such as vitamin C are generated in very high doses in many animals. Either it's not detrimental or if it is it beg the question why the animal would evolve such high levels in itself.

IIRC, the membranes of the longest living cells in mammals are more vulnerable to oxidation and rely on strong antioxidant protection to protect the cells and allow for their long lifespan.

Some antioxidant rich substances such as green tea and chocolate have been shown to be beneficial and probably help square survival curve of humans.

Posted by: Darian Smith at February 6th, 2014 3:04 PM

If this were true, I and Dr. Denham Harmons' "cancer-prone strains" of mice. would be long dead not living longer than "average" & "maximum". His synthetic anti-oxident has now been found to exist in nature, as well as in my body. As for Ascorbic acid, I can't calculate the 1,000's+ of studies showing benefit, both cancer & lifespan.

Posted by: Ray at February 11th, 2014 1:28 PM
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