Oxidative Stress

March 17th, 2009 | Sources: BurrillReport, PLoS Medicine


For decades, scientists theorized that aging was caused by oxidative stress, a phenomenon in which cellular damage is caused by free radicals and nasty oxygen-based molecules that build up over time as byproducts of normal biological processes.

freeradicalAccording to the theory, the cellular defense against the culprits-which are enzymes known as superoxide dismutases-gets overwhelmed by the accumulating bad guys and the next thing you know, cells are looking like Methuselah.

From the theory sprung an entire industry hawking antioxidant therapies from Vitamin A to Coenzyme Q which supposedly boosted the body’s ability to water-cannon the free radicals.

Alas clinical trials have never shown them to work and now McGill University scientists are raising doubts about the validity of the oxidative stress theory itself.

Siegfried Hekimi and colleagues disabled one-by-one, 5 genes coding for superoxide dismutases in a worm that goes by the unassuming name C. elegans.

The successive gene deletions did not shorten the worms’ lifespan; in fact in one instance, the altered critters outlived the wild-types.

The report is in PloS Genetics.

bagtheCoenzymeQ?Come to think of it, the evidence supporting the oxidative stress theory is circumstantial, Hekimi told BurrillReport.

And oxidative stress could be the result of aging rather than its cause.

“It is true that the more an organism appears aged, whether in terms of disease, or appearance or anything you care to measure, the more it seems to be suffering from oxidative stress. (But) people think correlation is causation,” he told BurrillReport.
Hekimi’s not saying oxidative stress is actually a good thing. It clearly interferes with normal cellular functioning. But it’s a stretch, he says, to say that oxidative stress causes aging.



  1. RKB | 4/04/09

    Thank you for this thought provoking article. I found a blog that addresses some of the issues created by oxidative stress and the ‘oxygen paradox’ that we face. I thought that your readers might be interested:

  2. Yena | 15/02/12

    Great insights, and thanks for taking time to share it. I was even disgusted by it and if possible get rid of it as long as I can. I even have bookmark it and share it with my friends.

Add Your Comment

You must be logged in to post a comment.

We just want the site to look nice!
  • Comment Policy

    Pizaazz encourages the posting of comments that are pertinent to issues raised in our posts. The appearance of a comment on Pizaazz does not imply that we agree with or endorse it.

    We do not accept comments containing profanity, spam, unapproved advertising, or unreasonably hateful statements.

Contact us if interested