Resveratrol, wine and the 'French paradox' - latest fad or miracle health cure?
We talk to Dr John D'Arcy - plus video of Barbara Walters and Prof. Sinclair on resveratrol
By Robyn Lewis
There’s been a lot in the news lately about resveratrol, a compound found naturally in the skins of red wine grapes, mulberries and other plants such as Japanese knotweed – and in wine, particularly red wine.
Resveratrol is one of a family of compounds made naturally by some plants when they are under attack by bacteria or fungi, and it appears that it may have beneficial effects on humans too, including anti-cancer, anti-inflammatory, blood-sugar-lowering and other cardiovascular benefits.
It’s also being touted as the latest anti-aging, energy-boosting, weight-shedding miracle food supplement - with resveratrol extract pills now being made from knotweed and red wine skins and claiming benefits from protection from brain degeneration to treating insulin resistance. Interestingly, knotweed root extract has been an ingredient long-used in traditional Chinese medicine.
Indeed, wine and doctors have gone together in Western medicine for a very long time indeed, and Australia’s first vine cuttings and those of Dr Christopher Rawson Penfold were brought to this country for medicinal purposes.
What is resveratrol, and does it work?
VisitVineyards.com is a keen supporter of the Australian Heart Foundation. We asked Dr John D’Arcy - Australia’s best-known media doctor who is well known for his concern about heart disease - what he thinks about resveratrol:
‘We all know about antioxidants which are valuable molecules that scout around our system seeking out free radicals. Now these are the internal rust buckets of our system. Just as an apple which has been sliced and left for a while discolours or oxidises, the same is true of the body and it’s the free radicals which do the oxidation or rusting if you like.
Oxidation is part of the ageing system so anything which slows it down may be a benefit. Resveratrol is an antioxidant and compared to the many others we get by eating fresh food, it’s a very good one.’
What does it actually do in the body?
‘The research which was announced by Harvard Medical School and the National Institute of Ageing back in 2006 was on obese mice. Now before you start pointing out the difference between mice and men let me say that mice are closer to us than some of the other organisms which have been treated with resveratrol (such as yeasts, worms, fruit flies and fish).
The fat mice on resveratrol treatment suffered less insulin resistance and less diabetes and their hearts came off better as well.
A company called Sirtris is just starting human trials in humans with diabetes with an anti-aging formulation of resveratrol.’
Wikipedia notes: ‘Experiments have shown that resveratrol treatment extended the life of fruit flies, nematode worms and short-living fish but it did not increase the life span of mice.’ So, on human ageing it’s probably too early to tell.
What are its effects on the heart?
‘The hearts of the fattened mice on resveratrol were much less ravaged than those without it. The pathologist was looking for areas of fat, a response to damage of the tissue and found a significant shortage of it.’
Resveratrol is also found in wine. It seems to be concentrated or even made in the wine making process, so wine – especially red wine – contains more resveratrol than grape juice alone. Heavier red wines have more than lighter reds, which in turn have more than white wine. There are wines which are now being made by leaving the fruit in contact with the skins, or passing the wine through skins a second time, so these might also contain more resveratrol.
We asked Dr D’Arcy is resveratrol present in wine in sufficient quantities to make any difference?
‘That fact isn’t known yet but I like the comment of Professor David Sinclair of the Harvard Medical School who is working with it: "And we will celebrate each new solution with a glass of red wine."
Professor Sinclair is investigating several critical genes that control the rate of ageing, diet restriction and resveratrol (see video below).
What about the so-called ‘French paradox’?
Wikipedia states: ‘Resveratrol is found in the skin of red grapes and is a constituent of red wine, but apparently not in sufficient amounts to explain the ‘French paradox’.
To explain all this we sought out another doctor who also happens to be a winemaker, this time Dr George Mihaly of the esteemed Paradigm Hill on the eastern side of Victoria’s Mornington Peninsula, which produces elegant cool climate wines.
Dr Mihaly is not a medical practitioner but a pharmacologist by training: ‘I was formerly involved in a medical research career developing new medicines – and most recently I set up and ran my own biotechnology R&D company before moving to another branch of biotech – called winegrowing!
As for which medicines, I’ve been involved in the selected stages of development of a wide range - from anticancer treatments to cardiovascular diseases and most recently, new medicines to hopefully treat Alzheimers.’
Firstly though let’s look at the so-called ‘French paradox’, which is the observation (first made in 1819) that the French may suffer a relatively low incidence of coronary heart disease despite having a diet relatively rich in saturated fats.
Various hypotheses have been put forward to explain this, including that the French consume more red wine, to the simple fact that they don’t snack between meals, take more time to eat their food and thus eat less compared with the average American or Australian for example.
We asked Dr Mihaly what he thought, and about resveratrol in his wines:
‘The exact cause for the French paradox remains elusive. Nonetheless, resveratrol has been put forward as the possible candidate because of a range of antioxidant and potential therapeutic activities suggested by a wide range of lab experiments.
However resveratrol is only one of a family of related, naturally occurring substances that are formed in grape skins. It may well be that resveratrol exerts its putative beneficial effect through its own action or maybe it does so through a combined effect with these other similar molecules. This is yet to be proven.
Whilst it has been suggested that one would have to ingest huge amounts of red wine to get enough resveratrol to be ‘therapeutic’, it is worth noting that in natural red wine there is the collective role of the structural analogues (ie similar molecules) to resveratrol.’
In other words, it may not be acting alone.
Let’s look some more at how it’s formed in grapes:
‘As red wine is fermented on skins, resveratrol is present in much higher levels in red wine than in white wine. Resveratrol is formed in skins as a response by the vine to the level of microbiological disease pressure (ie moist/cold conditions).
It appears that the levels of resveratrol are higher in red wines from cooler areas than from warmer areas – possibly because the levels of disease pressure is higher in cool, moist environments.
Whilst the actual substance resveratrol is present at fairly low levels in finished wine (usually 2mg/litre to 10 mg/litre), it has been an interest of mine to monitor the levels in Paradigm Hill wines to see how the levels vary:
- from one season top the next
- between red and white wines
- between different clones of pinot noir (MV6 and 115)
- between different red wines (pinot noir and shiraz)
Paradigm Hill is one of the few if not the only vineyard in Australia to quote its resveratrol levels on the label. We asked Dr Mihaly why?
‘I include the levels on our back label purely out of interest. I get the AWRI to do the measurements for me because it requires highly specialised lab equipment.
It’s still too early to be definitive but my observations suggest that:
- cooler [wetter] seasons result in higher levels
- red is far higher than white [where it is barely detectable]
- clones show definite pattern
- grape variety shows no definite pattern
We had previously spoken with ‘the wine doctor’ Dr Philip Norrie, who for many years has researched the relationship between wine, doctors and health. As well as being a medical doctor, he has completed a Ph.D. on the history of wine in medicine and with his wife co-owns a vineyard in the Hunter Valley, Pendarves Estate.
Dr Norrie is now behind the production of the world’s first resveratrol-enhanced wine (REW), made by a process which he has patented and is licencing out. Currently REW is only available in Australia.
He claims that this new antioxidant resveratrol-enhanced wine makes all other wines redundant from a health point of view. On his website Dr Norrie states that: ‘The best way to treat a disease is to not get it in the first place, hence the move away from treating disease to preventing disease.'
'The Holy Grail of the wine industry and oenotherapy (wine therapy) has been to produce a resveratrol-enhanced or enriched thus, healthier wine as the best preventative medicine to slow down the aging process and therefore extend human life expectancy.’
Dr Mihaly states: ‘I am not sure what to make of the idea of “resveratrol-enhanced wines". It would presumably depend on how much resveratrol the wine contains, and at what levels these are beneficial, relative to the amount of alcohol in wine, which over a certain level (two glasses per day for men and one per day for women, according to Dr John D’Arcy and the Heart Foundation) is bad for you.
The Wine Doctor's wines are claimed to contain up to 100 times more of the powerful anti-oxidant resveratrol than is found naturally in wine, which based on Dr Mihaly’s resveratrol levels would be from 200mg/litre to 1000 mg/litre.
A litre is far more than the average recommended daily allowance of wine. So one 100 ml glass may contain anywhere between 20-100 mg of resveratrol - the concentrations are not published on their website, and I don't have a back label to consult.
It all gets a bit more confusing after a trip to the pharmacy - one brand of resveratrol capsules contains 18 mg of 'resveratrol equivalent' with a dosage of one per day, another claims to contain 250 mg, with a recommended dosage of two per day. Perhaps until some more research is done and dosages are defined it's best to err on the side of caution, for after all, all drugs have side effects.
So like most things to do with our health, the jury is still out. Resveratrol does appear to be good for you, but whether it acts better with related compounds that occur naturally in wine, or whether it can act alone as in a dietary supplement pill, remains unknown.
One thing’s for sure, though, those early doctors – and many current ones – were onto a good thing with their red wines. In moderation of course, Dr John!
VisitVineyards.com promotes the responsible consumption of alcohol, by adults only (over the age of 18 in Australia).
Dr John D’Arcy
Dr Philip Norrie
Information about alcohol-related health issues and Australian Government policy
Prof. David A. Sinclair
The Heart Foundation
Wikipedia on resveratrol
See more links and related articles and products below.
When researching this article the author ordered a trial sample of resveratrol tablets from a company called Viv3 based in the UK. The terms and conditions were very carefully checked and there was no mention of any follow up fees. Their receipt was also very carefully scrutinised on arrival, again with no mention of any further charges or 'cancellation period'.
However I now have two unauthorised transactions on my credit card and further internet research now shows that this company is operating a scam, apparently based in Barcelona. Yes you get the trial sample but you also get ongoing monthly charges which can apparently only be remedied by cancelling your credit card. To read more complaints about Viv3's resveratrol unauthorised billing and what you can do about it please go here. Sadly, operations like this will only give the product a bad name.
Contact the credit card department of your bank immediately. I am pleased to report that mine responded very positively and there is some chance that I may get a refund.
Menawhile, listen to American presenter Barbara Walters talk to Prof. Sinclair about resveratrol
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