[quote]bmn wrote:
Here’s an interesting article I came across today:
Vitamin supplements may cut benefits of exercise
'Free radicals aren’t always the bad guys. It even seems that popping antioxidants to mop them up might reduce some of the beneficial effects of exercise.
Free radicals have long been thought to contribute to the ageing process, which is one reason why people take antioxidant supplements such as vitamin C or E.
However, other studies have hinted that taking antioxidants may hasten death through an unknown mechanism. One possibility is that they interfere with the beneficial effects of exercise, as there are hints that free radicals might be used by the body to prevent cellular damage after exercise.
(…)
Exercise is well known to have a beneficial effect on insulin resistance â?? a precursor condition to type 2 diabetes. However, when Ristow’s team measured the effects of exercise on insulin sensitivity, they found no increase in those volunteers taking antioxidants, but a significant increase in those who didn’t take the supplements."[/quote]
Very interesting stuff. In the past few years, I have been cautious about taking multi vitamins, or mega doses of any one vitamin. I think no matter the amount of research, we will always come back to “let food be thy medicine.”
Another interesting related article, if you click the link in the first sentence in the article “popping antioxidants to mop them up,” it takes you to this article:
The article points out those studies on single antioxidants (including Vit. C, A, and E) have shown at best little to no benefit and even harm in some instances. Now I don’t want to start some hysteria against antioxidants, but the article is very convincing that the benefits of supplemental antioxidants are not a given.
From the article, “the conclusion is becoming clear: whatever is behind the health benefits of a diet rich in fruits and vegetables, you cannot reproduce it by taking purified extracts or vitamin supplements. Just because a food with a certain compound in it is beneficial, it does not mean a nutraceutical [with the same compound in] is… People eating diets abundant in vitamin C, vitamin E, polyphenols and carotenoids (from food) are less likely to suffer heart attacks, vascular disease, diabetes and cancer.”
Several possible explanations are theorized in the article:
- people who eat diets rich in vitamins have a generally healthier lifestyle (exercise more and smoke less)
- polyphenols, carotenoids and vitamins in fruit and vegetables are bound into tough, fibrous material, they hang around in the stomach and colon, where they can neutralise free radicals. The gastrointestinal tract, especially the stomach with its highly acidic environment, is constantly generating reactive oxygen species from food. Supplements may not replicate this effect because they are digested too quickly.
- Nutrients work in concert with each other (suggesting that an extracted nutrient will not work in megadoses, or out of context of the other nutrients in the food).
- The more intriguing explanation: Whole foods with antioxidants in them also contain oxidants. There is the possibility that the oxidants can help nudge our own internal antioxidant systems into action. For example: “Among the leading sources of dietary antioxidants are tea and coffee, and there is some evidence that green tea in particular is linked with health benefits including reduced risk of cancer and cardiovascular disease. Oddly, though, Halliwell has discovered that tea and coffee are also bursting with reactive oxygen species in the form of hydrogen peroxide (because antioxidants are present with oxidants in nature - oxygen is all around us and is unavoidable).”
The article concludes with: "For now, the advice is simple. “Stick to flavonoid-rich foods, red wine in moderation, tea, fruits and vegetables,” says Halliwell. “Don’t start taking high-dose supplements or heavily fortified foods, until we know more.”
I think the first 3 theories hypothesized have some if not a considerable amount of weight. The fourth theory is pretty interesting, and I’m not sure if it does or does not hold weight. I’d be curious to know if it is a valid theory, and if so which supplements would still fit the bill. For instance, would a green tea extract be okay?
After reading this article I want to still further investigate the interactions of antioxidants. I wonder now if supplemental antioxidants are effective whatsoever, but still I want to research the interactions among antioxidants to understand how synergies can be achieved through other means, i.e. can maximum benefit be reached through combining a certain mixture of fruit/vegetable/&herbs.
Though the research brought extracted antioxidants into question, it did not bring into question a supplement like Superfood, which would seem to address theory #3 above (Nutrients work in concert with each other).
Under the four theories above, Superfood looks like a great product in all but theory #2 (antioxidants are bound into tough, fibrous material) because it is digested too quickly. I’ll attempt to find some additional research on this and propose whether an enteric coated Superfood tablet would provide significant improvement in efficacy.
I wonder though, if tea is known to reduce the risk of cancer and cardiovascular disease, then would its benefits be increased via bypassing the stomach (enteric coated tablets), or is theory #2 not valid?
