South African red and white wine is good for the heart. So drink up, says scientists, it's cheap medicine.
A group of researchers from the University of Cape Town (UCT) set out to see if South African wines extended the same heart benefits as those tested in international studies, and whether white wine held the same benefits as red.
"The study found that regular and moderate wine consumption (two to three glasses per day) protects against a heart attack by reducing cell death and improving the contractility [part of the healthy pumping action] of the heart," said UCT associate professor Sandrine Lecour. She was commenting on research presented by Zulfah Albertyn at a conference of the Physiology Society of Southern Africa recently held at Stellenbosch University.
To determine whether white wine held the same benefits as red, the researchers added either Pinot Noir (red), Pinotage (red) or Sauvignon Blanc (white) to the water of different groups of mice. After two weeks of "treatment", the hearts of mice and the hearts of the rats - subjected to a simulated heart attack in both the red and white study groups - showed improved heart functioning over a control group of mice who only had water. Although both the red and white wine groups showed benefits, the rats in the red wine group performed slightly better than those in the white wine group.
It is thought that the resveratrol (a polyphenol chemical found in red wine) may be responsible for the heart-protective properties, although it still needs to be scientifically proven added Lecour, who is also the deputy director of the Hatter Cardiovascular Research Institute at UCT. Although the benefits of resveratrol were not studied in this research, high levels of it were found in South African wines.
The UCT researchers focused on another compound, melatonin, which was recently discovered in grapes. Melatonin is a hormone that naturally occurs in humans and is known to regulate sleeping patterns. "The data showed that melatonin, a powerful antioxidant, is present in both red and white South African wines," said Lecour. This suggests that "chronic and moderate consumption of both red and white wine can protect against a heart attack."
"South African wines showed higher levels of melatonin than European wines," Albertyn said in her presentation. "So it may even be better."
The research also showed that the benefits of grape varieties differ in resveratrol and melatonin levels, and therefore possibly also in their heart-protective effects. "There are many factors that play a role in the cardio-protective effects of the wine, and this has to do with the type of grapes, the vineyard, the location, and it has to do with the fermentation process as well," said Albertyn.
"The take home message is that chronic consumption of South African red and white wines could potentially be cardio-protective, and the resveratrol and melatonin are inexpensive therapeutic tools against heart attack," said Albertyn.
The researchers also warned that although regular and moderate wine consumption may be beneficial to your health, excessive use of alcohol is one of the greatest risk factors for developing heart disease, and should therefore be used in moderation.