It was hard to miss the story recently which trumpeted the miraculous, health-preserving properties of a plant chemical in red wine known as resveratrol.
Recent research conducted at Harvard Medical School in the USA found that feeding mice with resveratrol helped counteract the ill effects of a fatty, calorie-laden diet.
Unfortunately, the results of studies in mice (or species such as guinea pigs, rats, monkeys, rabbits and dogs for that matter) do not necessarily transfer to humans. Also despite the headlines such as "Red wine helps extend life" and "Red wine really is healthy for us" the fact is the dosage of resveratrol used in the recent study in mice is equivalent to drinking about 100 bottles of red wine a day.
The headlines referring to red wine reminded me of the eminently healthy reputation this drink has. It is red wine, we are told, that is the likely reason why French folk who eat animal fat and have elevated levels of cholesterol in their bloodstreams have general immunity to heart disease. The supposed health-giving properties of red wine are usually quoted as an explanation for this French "paradox".
But is drinking red wine really as healthy as some would have us believe? For a start, even if alcohol can help spare us a heart attack, this condition only accounts for about a quarter of deaths.
Alcohol actually increases the risk of other potential killers including cancer. Factor such things into the equation and the apparent benefits of alcohol, essentially evaporate[1].
Also, while red wine is often touted as the tipple of choice by health professionals, it is has been shown that wine drinkers, compared to those who generally choose other forms of alcohol (beer and spirits) tend to eat healthier diets and smoke less too. The science shows that it's not the wine drinking per se , but other factors associated with red wine drinking that account for the apparent "benefits" of wine drinking[2-4].
The whole concept of the French paradox is based on the notion that eating animal fat and having raised levels of cholesterol is perilous for health.
Conventional wisdom dictates that a diet rich in saturated fat found in animal products such as meat, eggs and dairy products, and the higher blood levels of cholesterol this is said to induce, increase the risk of the artery-furring process that gives rise to heart disease.
This concept dates back to 1953, when an American researcher by the name of Ancel Keys published a study showing that the higher the level of fat in a nation's diet, the greater its rate of heart disease[5]. Other research performed over the last half-century have shown similar results, and have been bolstered by additional studies linking higher levels of cholesterol in the bloodstream to increased risk of heart disease too.
However, the case against saturated fat and cholesterol may not be as open-and-shut as we have been led to believe. When Keys published his seminal study 50 years ago, he focused on just six countries. However, at that time, data from 22 countries existed, which suggests Keys had been a tad selective about the evidence he presented.
Actually, much of the data Keys omitted did not fit into the neat little concept he was keen to popularise. For instance, despite similar fat intakes, heart disease deaths in Finland were found to be seven times higher than in Mexico. Also, deeper excavation has found enormous variance in heart disease rates within countries, despite similar dietary habits.
It's perhaps also worth bearing in mind that of the two-dozen-odd studies that have looked at the association between saturated fat and heart disease risk in the last half-century, all but a handful have found no association. Never mind that though, because as we're repeatedly told, eating saturated fat boosts blood levels of cholesterol, and that will get us in the end.
However, this association seems to be largely confined to relatively young individuals. Beyond middle age, higher cholesterol levels are not associated with adverse effects on health. Actually, in the elderly, some studies have found that raised cholesterol levels are associated with positive health benefits. Despite these facts, there are some who continue to bang the anti-cholesterol drum, and cite evidence to support this in the form of studies which show that cholesterol-reducing medications known as statins can reduce the risk of heart disease.
However, some researchers have suggested that the disease-protective benefits of statins come not from their cholesterol-quelling action, but from other biochemical effects they are known to have in the body. For instance, statins have anti-inflammatory effects, and inflammation is believed to be an important underlying process in heart disease.
The concept that cholesterol is not the spectre it's so often made out to be is supported by the fact that taking dietary steps to reduce cholesterol does not save lives[6]. It seems that eating animal fat and having lofty levels of cholesterol in the bloodstream are not the perilous risk factors in heart disease they are generally made out to be. The explanation for the French paradox is not red wine nor anything else come to that. The fact is the French "paradox" doesn't need an explanation, because it really is not a paradox at all.
References:
1. White IR, et al. Alcohol consumption and mortality: modelling risks for men and women at different ages. BMJ 2002;325:191
2. McCann SE, et al. Alcoholic beverage preference and characteristics of drinkers and nondrinkers in western New York" (United States). Nutr Metab Cardiovasc Dis. 2003;13(1):2-11
3. Tjonneland AM, et al. The connection between food and alcohol intake habits among 48, 763 Danish men and women. A cross-sectional study in the project "Food, cancer and health". Ugeskr Laeger 1999;161(50):6923-7
4. Barefoot J C, et al. Alcohol beverage preference, diet and health habits in the UNC Alumni Heart Study. Am J Clin Nutr 2002;76(2):466-72
5. Studer M, et al. Effect of different antilipidemic agents and diets on mortality. Archives of Internal Medicine. 2005;165:725-730
6. Keys A. Atherosclerosis: a problem in new public health. Journal of Mount Sinai Hospital. 1953;20:118-139
Dr. John Briffa is a London-based doctor, author and health writer with a special interest in nutrition and natural medicine. His website is www.drbriffa.com
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