Navigation Links
Antioxidants -- too much of a good thing?
Date:7/21/2013

In older men, a natural antioxidant compound found in red grapes and other plants -- called resveratrol -- blocks many of the cardiovascular benefits of exercise, according to research published today [22 July 2013] in The Journal of Physiology.

Resveratrol has received widespread attention as a possible anti-aging compound and is now widely available as a dietary supplement; much has been made of its role in explaining the cardiovascular health benefits of red wine, and other foods. But now, new research at The University of Copenhagen surprisingly suggests that eating a diet rich in antioxidants may actually counteract many of the health benefits of exercise, including reduced blood pressure and cholesterol.

In contrast to earlier studies in animals in which resveratrol improved the cardiovascular benefits of exercise, this study in humans has provided surprising and strong evidence that in older men, resveratrol has the opposite effect.

What is emerging is a new view that antioxidants are not a fix for everything, and that some degree of oxidant stress may be necessary for the body to work correctly. This pivotal study suggests that reactive oxygen species, generally thought of as causing aging and disease, may be a necessary signal that causes healthy adaptations in response to stresses like exercise. So too much of a good thing (like antioxidants in the diet) may actually be detrimental to our health.

Lasse Gliemann, a PhD student who worked on the study at The University of Copenhagen, explains how they conducted the research, and the results they found: "We studied 27 healthy, physically inactive men around 65 years old for 8 weeks. During the 8 weeks all of the men performed high-intensity exercise training and half of the group received 250 mg of resveratrol daily, whereas the other group received a placebo pill (a pill containing no active ingredient). The study design was double-blinded, thus neither the subjects nor the investigators knew which participant that received either resveratrol or placebo.

"We found that exercise training was highly effective in improving cardiovascular health parameters, but resveratrol supplementation attenuated the positive effects of training on several parameters including blood pressure, plasma lipid concentrations and maximal oxygen uptake."

Ylva Hellsten, the leader of the project, says:"We were surprised to find that resveratrol supplementation in aged men blunts the positive effects of exercise training on cardiovascular health parameters, in part because our results contradict findings in animal studies.

"It should be noted that the quantities of resveratrol given in our research study are much higher than what could be obtained by intake of natural foods."

This research adds to the growing body of evidence questioning the positive effects of antioxidant supplementation in humans.

Michael Joyner, from The Mayo Clinic USA, says how the study has wider implications for research: "In addition to the surprising findings on exercise and resveratrol, this study shows the continuing need for mechanistic studies in humans. Too often human studies focus on large scale outcomes and clinical trials and not on understanding the basic biology of how we adapt."


'/>"/>

Contact: Lucy Holmes
lholmes@physoc.org
44-020-726-95727
Wiley
Source:Eurekalert

Related biology news :

1. Antioxidants may ease PAD blood pressure increase
2. Diet high in total antioxidants associated with lower risk of myocardial infarction in women
3. Powerful class of antioxidants may be potent Parkinsons treatment
4. Too much of a good thing? Too many healing cells delays wound healing
5. Cant smell anything? This discovery may give you hope
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/2/2016)... The Department of Transport Management (DOTM) of ... project, for the , Supply and Delivery of ... Infrastructure , to Decatur , ... Management Solutions. Numerous renowned international vendors participated in the tendering ... selected for the most compliant and innovative solution. The contract ...
(Date:6/1/2016)... -- Favorable Government Initiatives Coupled With Implementation ... to Boost Global Biometrics System Market Through 2021  ... " Global Biometrics Market By Type, By End ... - 2021", the global biometrics market is projected to ... growing security concerns across various end use sectors such ...
(Date:5/16/2016)... YORK , May 16, 2016   EyeLock ... solutions, today announced the opening of an IoT Center ... to strengthen and expand the development of embedded iris ... an unprecedented level of convenience and security with unmatched ... authenticate one,s identity aside from DNA. EyeLock,s platform uses ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... 2016   Boston Biomedical , an industry ... to target cancer stemness pathways, announced that its ... Drug Designation from the U.S. Food and Drug ... including gastroesophageal junction (GEJ) cancer. Napabucasin is an ... cancer stemness pathways by targeting STAT3, and is ...
(Date:6/23/2016)... SPRING, Md. , June 23, 2016 A ... collected from the crime scene to track the criminal down. ... and the U.S. Food and Drug Administration (FDA) uses DNA ... Sound far-fetched? It,s not. The ... genome sequencing to support investigations of foodborne illnesses. Put as ...
(Date:6/23/2016)... ... June 23, 2016 , ... Charm Sciences, ... microbial test has received AOAC Research Institute approval 061601. , “This is another ... year,” stated Bob Salter, Vice President of Regulatory and Industrial Affairs. “The Peel ...
(Date:6/23/2016)...  The Biodesign Challenge (BDC), a university competition that ... living systems and biotechnology, announced its winning teams at ... New York City . The teams, ... at MoMA,s Celeste Bartos Theater during the daylong summit. ... curator of architecture and design, and Suzanne Lee ...
Breaking Biology Technology: