Longevity Briefs: Can Antioxidants Like Resveratrol Slow Ageing After The Menopause?

Longevity briefs provides a short summary of novel research in biology, medicine, or biotechnology that caught the attention of our researchers in Oxford, due to its potential to improve our health, wellbeing, and longevity.

The problem:

Studies suggest that menopause is associated with an acceleration of overall biological ageing, not just reproductive ageing. The hormonal changes that occur during the menopause lead to an increased risk of many age related diseases including diabetes and heart disease. One component of this accelerated ageing is an increase in oxidative stress. Oxidative stress occurs when free radicals – highly reactive byproducts of our metabolism – damage important molecules like proteins and genetic material. 

Antioxidants are molecules that can neutralise free radicals by reacting with them in the place of something more important. The body produces its own antioxidants, but antioxidant capacity may be improved by consuming foods and supplements containing antioxidant compounds. In this clinical trial, researchers investigate the potential for two such compounds – resveratrol and vitamin C – to combat oxidative stress in postmenopausal women, and maybe mitigate some its health impact.

The discovery:

The researchers recruited 42 women aged 50-60 who were all postmenopausal and who all showed a degree of resistance to the blood sugar lowering hormone insulin, but did not have diabetes. They also excluded women taking hormone replacement therapy or certain drugs, including those with antioxidant activity. They then randomly assigned participants to take either resveratrol and vitamin C, resveratrol and a placebo, or vitamin C and a placebo for three months. There was no group taking only placebo, as the authors were more interested in comparing the effects of resveratrol or vitamin C alone with combined treatment.

At the end of the three months, blood tests showed that all treatment combinations had beneficial effects on oxidative stress, though which combination came out on top varied depending on exactly what was measured. When measuring lipohydroperoxides, a marker of oxidative damage to lipids, only resveratrol + vitamin C led to a statistically significant reduction (of 33%) compared to the start of the study. However, when measuring malondialdehyde, another marker of lipid oxidation, vitamin C alone appeared most effective, with a 38% reduction. When it came to oxidative damage to proteins, combined resveratrol and vitamin C was more effective, with a 39% reduction. Combined treatment also appeared slightly more effective in boosting total antioxidant capacity, with a 30% increase vs 28% for vitamin C alone and no statistically significant change for resveratrol.

Unfortunately, none of the groups in this study saw any improvements in their insulin sensitivity compared to when the study began. The researchers also observed that participants in the vitamin C group had significantly higher triglyceride levels than the other two groups at the end of the study.

The implications:

Resveratrol and vitamin C may have some benefit in lowering oxidative stress in postmenopausal women, though since there was no control group taking only placebo treatments, we do not know what would have happened to oxidative stress levels if the participants had not been taking either compound. However, since resveratrol and vitamin C are already established to be antioxidants, the authors mainly wanted to compare the treatments with eachother and with combined use. It seems as though there is not yet enough evidence to say that resveratrol and vitamin C together is superior to either treatment alone – more studies with larger sample sizes will be needed to answer that question.

Of course when it comes to health and ageing, a reduction in oxidative stress alone doesn’t mean much. What we would really like to know is whether reduced oxidative stress when taking either of these compounds translates to tangible health benefits such as reduced risk of age-related disease. Answering that question requires not only larger sample sizes, but also clinical trials that last much longer, so that age-related diseases have time to develop.