Too Much of a Good Thing Can Mean Trouble
Is your body getting all the oxidants you need? Yes, you read that right… this is a bit of advice I bet you haven’t heard before: Our bodies actually require oxidants… and more and more evidence is piling up that overenthusiastic consumption of antioxidant supplements has serious consequences.
Oxidants & Health
It turns out that good health requires hanging onto some oxidants — especially if you exercise regularly. While research had already demonstrated that exercise boosts the body’s level of a type of oxidant called reactive oxygen species(ROS), scientists initially thought it indicated a need for more antioxidants. Researchers at the Cardiorespiratory Exercise Laboratory at Kansas State University (Manhattan) have now learned that some oxidants (hydrogen peroxide, for instance) act as vasodilators (expanding blood vessel walls) to increase delivery of oxygen to muscles — getting rid of them with antioxidants impairs that process. The studies also revealed that a very high level of antioxidants interferes with the natural regulatory systems that help muscles to function properly.
Yet another study, this one done with mice at Monash University in Australia (Melbourne), found that oxidants can help hold back the onset of type 2 diabetes. They help prevent insulin resistance, a hallmark of impending diabetes, by improving the body’s ability to respond appropriately to insulin signals. The mice given antioxidants developed diabetes at higher rates than the control group even though their high-fat diets were otherwise the same.
And a third study, a very early one from Cedars-Sinai Heart Institute in Los Angeles, finds that high doses of antioxidant supplements may boost cancer risk. More research is needed on this preliminary finding, and it doesn’t pinpoint the level that may be dangerous, but even so it is yet more evidence that it’s possible to overdo antioxidant supplementation.
Oxidants for Good Health
Oxidants definitely have health benefits. Daily Health Newscontributing medical editor Andrew L. Rubman, ND, told me about some of the important functions they help fulfill…
- Oxidants help fight cancer. They weaken cell membranes to facilitate the natural destruction and turnover of tissue cells (apoptosis), including pre-cancerous tissue.
- Oxidants are important to heart health. Blood vessels need oxidants for proper function — in fact, patients with heart disease are prescribed the oxidant nitric oxide (in the form of nitroglycerin), which relieves angina by expanding cardiac arteries.
- Oxidants facilitate sexual satisfaction. When people are sexually aroused, oxidants expand appropriate blood vessels to allow for engorgement — it’s actually the mechanism responsible for making erectile dysfunction drugs work.
A Matter of Balance
It almost sounds as if oxidants are our new best friends, but Dr. Rubman stresses that balancebetween oxidants and antioxidants is what’s important — he describes it as “a dance between the two.”
The reality of the way most of us eat (lots of oxidants) combined with environmental challenges (such as pesticides, petrochemicals and plastics) means that most Americans are already skewed in the direction of oxidants, Dr. Rubman said. The best way to achieve and maintain appropriate balance is to eat plenty of whole foods that provide your body not only with the nutrients it needs, but also the enzymes and cofactors that optimize their absorption. If you aren’t sure your diet accomplishes that, antioxidant supplements may then be in order.
How to tell? Blood tests aren’t a great measure, as they fluctuate day to day, and you can’t always tell by how you feel, either. Dr. Rubman said a far better measure is to consider how your body copes with challenges. For instance, if you suffer from a mild seasonal allergy to pollen, high levels may bring congestion, but if you are “in balance” you should bounce back quickly without becoming stuffed-up and sick. Similarly, you may notice that your gym workouts aren’t achieving the results you’d expect — you’re not building muscle commensurate with the effort you are exerting. These subtle signs may be clues your system is overloaded with antioxidants — if you suspect that you have this problem, get advice from a doctor trained in the nuances of nutrition. He/she can help figure out how to achieve the right balance.
Meanwhile, I imagine we’ll be hearing more on this important topic in months and years to come — I’ll provide updates as they arise.