From a scientific perspective, are there health differences between red wine and red grape juice besides the alcohol?
Kat - This is a great one because everyone wants to know, ‘can I drink red wine and will it prevent cancer?’ The answer is yes there are chemical differences between grape juice and wine, the main one being the presence of alcohol. There are physiological differences between drinking and the main thing is that alcohol is a very effective solvent A lot of the sort of biological chemicals that may be found in wine can be dissolved into fat using alcohol. That’s why it’s a great solvent. You’ll probably be able to get more chemicals into your body by drinking wine and this is actually why if you smoke and drink at the same time you’ll actually do yourself a lot more harm than if you just smoke or just drank alcohol. Alcohol does help all these nasty chemicals pass into your body much more easily. In terms of the absolute health benefits of what’s in red wine the main culprit is called reveratrol and tabloids get very excited about this and say, “Red wine you should all drink this!” Resveratrol is a really interesting molecule and organisations like Cancer Research UK are investigating it to see if it can prevent cancer. The amount that you get in the average bottle of red wine is actually relatively small. A scientist told me before that you would have to drink hundreds of bottles of red wine a day to actually get enough resveratrol to have an effect. I think the actual differences are quite minimal between grape juice and wine in terms of health benefits. We’re actually investigating resveratrol as a more – you purify the chemical and give it to people that way. In terms of alcohol health benefits the research has shown that there’s benefits for heart type things: cardiovascular disease. In a very small group of people - and this is basically men over the age of 50 and women over menopause who drink one unit of alcohol per day [there may be health benefits]. But then alcohol does cause heart disease and strokes if you drink in reasonably large amounts. If you really want health benefits you’re best sticking to the grape juice.
Chris - There’s one other chemical in red wine which we should mention and that’s procyanadin. Roger Corder is a researcher at the London Hospital Medical College and St Bartholomew’s Medical College in London and he actually found out how this worked. You can find lots of procyanadin in tannat grapes which are in southwest France. So some of the grapes that grow at very high altitude. The reason you find that is because it’s an antioxidant molecule and it helps to protect the grapes from ultraviolet. If you put it into your body what Roger Corder found is that it helps to relax blood vessels. This is present in sufficiently high quantities in red wine that you would have at therapeutic levels, i.e. a glass at dinner. It will cause a reduction in things like blood pressure and heart disease and stroke risk. If you go and buy red wine look from tannat grapes because they’re the good ones.