Ageing theory questioned

Behind the Headlines

Wednesday December 3 2008

Many skin creams are based on antioxidant formulas

Vitamin supplements and face creams do not slow the ageing process according to reports in The Guardian and The Daily Mail. The newspapers report that the ‘antioxidant theory’ behind many anti-ageing products has been disproved by a new study.

The research investigated the widely accepted theory that oxidation is behind ageing by studying worms genetically engineered to be more vulnerable to the process. However, these vulnerable worms survived just as long as their normal counterparts did.

Study leader David Gems told The Guardian, ‘it really demonstrates finally that trying to boost your antioxidant levels is unlikely to have any effect on ageing’.

While this is valuable research into the effects that oxidation has upon lifespan and ageing in worms, one should be cautious applying its finding to humans. Also, the study has not tested anti-ageing products in humans, which some news reports may lead readers to assume.

The role of antioxidants and oxidation in human ageing still needs further research.

 

Where did the story come from?

This research was conducted by Ryan Doonan and colleagues of Institute of Healthy Ageing and Research Department of Genetics, Evolution and Environment, University College London, and Ghent University in Belgium.

 

It was funded by Wellcome Trust, Ghent University, the Fund for Scientific Research-Flanders, and the European Community. The study was published in the peer-reviewed scientific journal, Genes and Development.

 

What kind of scientific study was this?

This was a laboratory study investigating the role that a form of free radical (superoxide) has on ageing and lifespan in worms. The study further investigates the long-standing belief that ageing is caused by oxidative damage in the body, based on a theory proposed in 1956.

 

Superoxides are unbalanced oxygen molecules produced through natural processes in the body and can actually cause oxidative damage in the body.

The researchers investigated the roles of certain genes in a species of nematode worm, C elegans. These genes lead to the production of enzymes that remove superoxides, from the worm body. The enzymes involved in detoxifying superoxides are forms of superoxide dismutase (SOD)

The researchers manipulated the five genes that normally produce this enzyme to reduce the cells ability to mop up excess superoxides.

The researchers also explain how manipulating the genes affects function and developmental characteristics in the worm, specifically the role that the forms of SOD and the three main superoxide groups have upon life history and ageing.

 

What were the results of the study?

The researchers say that, as they expected, loss of the active SOD enzymes caused increased sensitivity to oxidative stress. However, they found that their manipulation of genes and subsequent loss of the SOD enzymes had no effect of the lifespan of the worms.

 

 

What interpretations did the researchers draw from these results?

The findings suggest that superoxides are not the major determiner of ageing in C. elegans worms. In an accompanying press release an author of the study says that, ‘the free radical theory of ageing has filled a knowledge vacuum for over 50 years now, but it just doesn't stand up to the evidence’. However, the actual mechanisms of ageing remain unknown.

 

The authors propose that chemical reactions in the body and the metabolism of sugars may be more likely to be involved in ageing. They also say that although a healthy balanced diet has many benefits, ‘there is no clear evidence that dietary antioxidants can slow or prevent ageing’.

 

What does the NHS Knowledge Service make of this study?

This is valuable research into the effects that oxides and antioxidants have upon lifespan and ageing in worms, however, applying the findings to humans is questionable. To some degree, the study has challenged the theory that oxides are the principle causes of ageing.

 

The study does not examine the antioxidant effects of supplements and skin creams in humans, which were mentioned in news reports. Many people are interested in antioxidant-based products as a means to look or feel younger, but equally the research does not investigate their affect on quality of life.

The research has not tested or made claims about any individual brands of cream, vitamin or antioxidant supplements. More research will be needed before the relevance of these findings for humans is clear, and in particular for the cosmetic and supplement manufacturers.

 

Sir Muir Gray adds...

That's bad news for worms, but I never took antioxidants anyway.

 

Analysis by Bazian

Edited by NHS Choices

Links to the headlines

Blow to vitamins as antidote to ageing. The Guardian, December 01 2008

Anti-ageing face creams ‘don’t work’ - exercise and eat sensibly instead, say scientists. Daily Mail, December 01 2008

Antioxidants 'cannot slow ageing'. BBC News, December 01 2008

Links to the science

Doonan R, McElwee JJ, Matthijssens F, et al. Against the oxidative damage theory of aging: superoxide dismutases protect against oxidative stress but have little or no effect on life span in Caenorhabditis elegans. Genes and Development 2008 [To be published]

Ratings

How helpful is this page?

Average rating

Based on 1 ratings

All ratings

0  ratings
0  ratings
0  ratings
0  ratings
1  ratings

Add your rating