photo: neatly sliced
By Research Nancy
(Hi there! This is Crabby poking her head in here to welcome Research Nancy back with another post full of actual research of the sort that I'm too lazy to sort through myself these days. You may recall she rounded up research on whether coffee is good or bad for you, and now she's looking into antioxidant supplements for us and finding some Most Unpleasant Surprises.)
Take it away, Research Nancy! --Crabby)
What happens when you find a good sale on the vitamins you like and purchase a 6 month supply? Sounds great! Well, maybe not when you discover there are a bunch of studies showing that antioxidant supplements may not help, in fact may be very bad for you. How’s that for saving money?
Let me start by first by saying this isn’t the first time we’ve heard this. Just goes to show you that Cranky Fitness was on to one aspect of the antioxidant vitamin problem back in 2009. (Note: I did not pay Nancy to say that! And in fact I totally forgot I wrote it.---Crabby.) Another reputable blog back in 2009 suggested that antioxidant supplements actually negated the effects of exercise in muscle tissue. And recently the New York Times reported on a study in Norway with the same conclusion: vitamins may be bad for your workout, and the BBC agrees.
What is going on here?
Aren’t free radicals bad for me? Won’t these antioxidants mow them down?
The Norwegian study, published recently in The Journal of Physiology, took 54 healthy adult men and women, most of them recreational runners or cyclists, and conducted a series of tests, including muscle biopsies, blood draws and treadmill runs, to establish their baseline endurance capacity and the cellular health of their muscles.
They divided the volunteers into two groups: One group took 4 placebos and one group took 4 pills for a total dose of 1,000 milligrams of vitamin C and 235 milligrams of vitamin E. All participants completed a vigorous 11-week training program, consisting of increasingly intense interval sessions once or twice per week, together with two weekly sessions of moderately paced hour-long runs.
While all participants were more fit at the end with max endurance capacity increasing on average by 8 per cent, the two groups showed different results in their mitochondria which generates energy in cells in the bloodstream and muscles. The group with placebos showed robust increases of biochemical markers that increase the creation of mitochondria. The creation of new mitochondria is, in fact, generally held to be one of the most important effects of exercise. The group that took the antioxidants had significantly lower levels of the markers related to mitochondrial creation.
In another study of older men, half took 250 milligrams daily of the supplement resveratrol, an antioxidant famously found in red wine, and the other half took a placebo. After two months of exercising, the men taking the placebo showed significant and favorable changes in their blood pressure, cholesterol profiles and arteries, with fewer evident arterial plaques. The men taking the resveratrol exercised as much as the other men, but their blood pressures, cholesterol levels and arteries had remained s almost unchanged.
The theory here is, “free radicals are not villainous but serve as messengers, nudging genes and other bodily systems into starting the various biochemical reactions that end in stronger muscles and better metabolic health. Without free radicals, those reactions don’t begin.” The reason we were taking the antioxidant supplements was to absorb most of the free radicals produced by exercise.
OK. but what if I’m not worried about my athletic performance but want to avoid health issues associated with free radicals?
Studies show that antioxidants can prevent programmed cell death (apoptosis). Well this sounds good, but is it? Having cells that ignore apoptosis signals is believed to be a common feature in carcinogenesis!
Back in 2009, researchers were already questioning the relationship between antioxidants and cancer, and more recently a study of lung cancer progression in mice as reported in The Scientist suggested that antioxidants could actually accelerate cancer. Per this research 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.
Frustated? I am! All the information I absorbed in the past said that antioxidant supplements and foods placed a role in preventing cancer. However, research is starting to suggest the opposite: that high levels of extra antioxidants can actually give people cancer, or at the very least, help along any cancerous cells that might arise on their own.
Get your antioxidants from real food; at least so far, the general consensus is that eating lots of fruits and vegetables is still good for you.
But anyone who still wants some antioxidant supplements? You can have mine!