French paradox

The overall impact of the popular perception, in the English-speaking world, that the French paradox is a real phenomenon, has been to give added credibility to health claims associated with specific French dietary practices.

This was seen most dramatically when, in 1991, an early account of the then-novel concept of the French paradox was aired in the United States on 60 Minutes. The broadcast left the impression that France's high levels of red wine consumption accounted for much of the country's lower incidence of cardiac disease. Within a year, the consumption of red wine in the United States had increased by 40%[8] and some wine sellers began promoting their products as "health food."[9]

The cultural impact of the French paradox can be seen in the large number of book titles in the diet-and-health field which purport to give the reader access to the secrets behind the paradox:

• The Fat Fallacy: The French Diet Secrets to Permanent Weight Loss (William Clower, 2003);
• The French Don't Diet Plan: 10 Simple Steps to Stay Thin for Life (William Clower, 2006)
• French Women Don't Get Fat (Mireille Guiliano, 2004, which became a #1 best-seller in 2006)
• Cholesterol and The French Paradox (Frank Cooper, 2009);
• The French Women Don't Get Fat Cookbook (Mireille Guiliano, 2010).

Other books sought to boost their credibility by reference to the French paradox. The American edition of The Dukan Diet, written by Pierre Dukan, a Paris-based doctor, is marketed with the subtitle, “The real reason the French stay thin.”

The existence of the French paradox has caused some researchers to speculate that the link between dietary consumption of saturated fats and coronary heart disease might not be as strong as had previously been imagined. This has resulted in a review of the earlier studies which had suggested this link.

Some researchers have thrown into question the entire claimed connection between natural saturated fat consumption and cardiovascular disease. In 2006, this view received some indirect support from the results of the Nurses' Health Study run by the Women's Health Initiative. After accumulating approximately 8 years of data on the diet and health of 49,000 post-menopausal American women, the researchers found that the balance of saturated versus unsaturated fats did not appear to affect heart disease risk, whereas the consumption of trans fat was associated with significantly increased risk of cardiovascular disease.[10]

Similarly, the authors of a 2009 review of dietary studies concluded that there was insufficient evidence to establish a causal link between consumption of saturated fats and coronary heart disease risk.[11]

It has been suggested that France's high red wine consumption is a primary factor in the trend. This hypothesis was expounded in a 60 Minutes broadcast in 1991.[12] The program catalysed a large increase in North American demand for red wines from around the world. It is believed that one of the components of red wine potentially related to this effect is resveratrol;[13] however, the authors of a 2003 study concluded that the amount of resveratrol absorbed by drinkers of red wine is small enough that it is unlikely to explain the paradox.[14]

Red wine was considered a possible explanation, but proved unlikely to explain the paradox

The difference between U.S. annual per capita alcohol consumption (9.2 litres per year)[15] and French consumption (12.2 litres per year) is only 3 litres per year.[16]

There is a lack of medical consensus about whether moderate consumption of beer, wine, or distilled spirits has a stronger association with longevity. Of ten major studies, three found stronger evidence for wine, three for beer, three for liquor, and one study found no difference between alcoholic beverages.[17]

Wines, particularly red wines, are a source of low levels of resveratrol. However, there is no high-quality evidence that resveratrol improves lifespan or has an effect on any human disease.[18][19]

Oligomeric procyanidins have been proposed to offer protection to human vascular cells,[20] with other research indicating that red wine polyphenols reduce absorption of malondialdehyde which is implicated in elevating levels of low-density lipoprotein in the onset of arteriosclerosis.[21]

However, once digested and metabolized, the role of polyphenols to assert possible health effects in humans cannot be determined.[22] Although polyphenols are speculated to be part of the health-promoting effects of wine consumption, no evidence exists to date that ingesting polyphenols from red wine or food sources actually provides health benefits.[23]

The French diet is based on natural saturated fats such as butter, cheese, and cream that the human body finds easy to metabolize because they are rich in shorter saturated fatty acids ranging from the 4-carbon butyric acid to the 16-carbon palmitic acid. The American diet includes greater amounts of saturated fats made via hydrogenating vegetable oils which include longer 18- and 20-carbon fatty acids. In addition, these hydrogenated fats include small quantities of trans fats which may have associated health risks.[24][25][26]

In his 2003 book, The Fat Fallacy: The French Diet Secrets to Permanent Weight Loss, Will Clower suggests the French paradox may be narrowed down to a few key factors, namely:

• Good fats versus bad fats — French people get up to 80% of their fat intake from dairy and vegetable sources, including whole milk, cheeses, and whole milk yogurt.
• Higher quantities of fish (at least three times a week).
• Smaller portions, eaten more slowly and divided among courses that let the body begin to digest food already consumed before more food is added.
• Lower sugar intake — American low-fat and no-fat foods often contain high concentrations of sugar. French diets avoid these products preferring full-fat versions without added sugar.
• Low incidence of snacks between meals.
• Avoidance of common American food items, such as soda, deep-fried foods, snack foods, and especially prepared foods which can typically make up a large percentage of the foods found in American grocery stores.

Clower tends to downplay the common beliefs that wine consumption and smoking are greatly responsible for the French paradox. While a higher percentage of French people smoke, this is not greatly higher than the U.S. (35% in France vs. 25% in U.S.) and is unlikely to account for the weight difference between countries.

Mireille Guiliano, author of the 2006 bestseller French Women Don't Get Fat,[27] agrees that the weight differences are not due to French smoking habits. She points out that the smoking rates for women in France and the U.S. are virtually identical.[28] Guiliano suggests that the key factors are:

• Smaller portion sizes: - she advocates the 50% rule, i.e. asking for half of whatever food one is offered, "la moitié, s'il vous plaît" in French [29]
• Savoring food to increase the feeling of satisfaction, choosing a small amount of high quality food rather than larger amounts of low quality food
• Eating 3 meals a day and not snacking
• Taking in plenty of liquid such as water, herbal tea and soup
• Sitting down and eating mindfully (no multitasking and eating while standing up, watching TV, or reading)
• Emphasizing freshness, variety, balance, and, above all, pleasure[28]

In his 2008 book In Defense of Food, Michael Pollan suggests the explanation is not any single nutrient, nor the amount of carbohydrates or fats or proteins, but the whole length and breadth of nutrients found in "natural" as opposed to "processed" foods.[30]

It has been suggested that a higher intake of fruit and vegetables in the diet may lower the risk of cardiovascular diseases.[31]

One proposed explanation of the French paradox regards possible effects (epigenetic or otherwise) of dietary improvements in the first months and years of life, exerted across multiple generations. Following defeat in the Franco-Prussian War in 1871, the French government introduced an aggressive nutritional program providing high quality foods to pregnant women and young children with the aim of fortifying future generations of soldiers (the program was implemented about three decades prior to an analogous initiative in England in response to the Boer War). It has been suggested that the particular timing of this historical intervention might help explain the relatively low rates of obesity and heart disease found in France.[32]