"It has often been observed that the French do not develop heart disease despite bad eating habits. This phenomenon, referred to as French Paradox has often been attributed, even by scientific studies, to the consumption of red wine which contains a chemical compound resveratrol which is beneficial for the heart and has anti-cancer properties," the study conducted by the Bio-chemistry department of Allahabad University says.

Prof Syed Ibrahim Rizvi, the author of the study, which was presented at the National Symposium on Advances in Clinical Biochemistry held in Aligarh in November, 2008, said "it has been baffling for scientists that under laboratory conditions, resveratrol is required in much higher amounts to show effects similar to what is observed under normal conditions".

"For example, the amount of resveratrol ingested through a glass of wine or a serving of red grapes, another important source of the compound, has not been sufficient to elicit health benefits in studies conducted under laboratory conditions," he said.

"The key to this phenomenon may be found in an enzymatic system present in the red blood cells, known as plasma membrane redox system (PMRS). The resveratrol that is ingested into the body through any source, donates electrons to the PMRS which is present in the red blood cells. These electrons are used by the PMRS to maintain the levels of ascorbic acid (Vitamin C) in the plasma," said Rizvi.

"Vitamin C is essential to regenerate Vitamin E which plays a very important role in preventing atherosclerosis, or hardening of the arteries, which in turn gives rise to several diseases related to the heart," Rizvi added.

"This phenomenon offers a possible explanation to the health-promoting effects of resveratrol, even when consumed in moderate concentrations. With this, people may also be rest assured that for health benefits, they need not consume large amounts of resveratrol-rich food like red wine, red grapes or pomegranate," he added.

Another important finding of the study has been that the rate of red blood cell PMRS increases during human aging. "It appears that the increase in PMRS activity is a defence mechanism of the human body to cope with increased oxidative stress during aging. Thus any compound which displays PMRS activating effect has a potential anti-aging effect," he added.

"This phenomenon offers a possible explanation to the health-promoting effects of resveratrol, even when consumed in moderate concentrations. With this, people may also be rest assured that for health benefits, they need not consume large amounts of resveratrol-rich food like red wine, red grapes or pomegranate," he added.