French Paradox
French Paradox
Research and general acceptance
Definition
The French Paradox refers to the low rate of coronary heart disease (CHD) in France despite the diet being rich in saturated fat.
Origins
2002 data from the Food and Agriculture Organization of the United Nations (FAO), showed that although the intake of saturated fat in France was higher than in the United States (US), 108 grams (g) compared to 72g per day, France had a 30–40% lower risk of CHD. Over the years, studies suggest that one of the reasons the French have a lower rate of CHD, despite higher saturated fat intakes, may be related to their regular consumption of red wine.
Links to alcohol and heart disease were first observed in 1976. English Physician William Heber-den’s classic descrition of angina pectoris, included ‘wines and liquors . . . afford considerable relief’. This led to the assumption that alcohol was a coronary vasodilator.
The French Paradox was first noted by Irish cardiologist Samuel Black in 1819. He found that the French had lower heart rate deaths compared to the Irish and attributed this to ‘the French habits and modes of living, coinciding with benignity of their climate and the peculiar character of their moral affections’. This was the beginning of more current thinking that other dietary and lifestyle factors may play a part in the risk for heart disease.
In the 1970s, epidemiological studies began to show that moderate intakes of alcohol were associated with a low rate of CHD. In 1997, a large American study by Thun et al., demonstrated that at least one drink a day reduced death risk from CHD, but more than three drinks daily was associated with an increased death rate. McElduff et al. followed this up in the same year and found that frequency was as important as quantity in risk for heart disease. Lowest risk was among those who drank moderate of alcohol amounts 4–6 days a week. At the time there were issues with defining heavy and moderate drinking and as of 2007 there is still some debate. However, there is a general agreement that 3 unit of alcohol a day for men and 2 or more a day for women is considered unhealthy.
It was not until the 1990s that the French Paradox was looked at again. Dr. Serge Renaud, a scientist from Bordeaux University in France, coined the term ‘French Paradox’ after his 1992 study. This was a large study of middle age French men. He found they have a long life expectancy despite a diet high in saturated fat. Although the diet included butter, cheese, eggs and cream, contributing to 15% of calories from saturated fats, the incidence of CHD was only 40% of the American incidence of CHD. He concluded that two to three glasses of wine a day wine reduced death rates from all disease by up to 30%, but four glasses a day were found to have an adverse effect on health. He suggested that the combined effect of the alcohol and antioxidants in wine played a role in reducing CHD. The French Paradox became internationally recognized when in 1991 he, together with another French Paradox supporter Dr. R. Curtis Ellison of Boston University School of Medicine, outlined the research on the ‘60 minutes’ documentary in the USA. Inter-estingly,soon after this, red wine sales in the United States increased by 40%.
Further studies have supported this hypothesis, including the 1995 Copenhagen Heart Study that ran from 1976 to 1988 and confirmed the health benefits of >
KEY TERMS
Angina— Pain that comes from the heart, caused by the narrowing of the coronary arteries.
Binge drinking— British Medical Association states there is no consensus on the definition of binge drinking, but is usually used to refer to heavy drinking over an evening or similar time span. Sometimes also referred to as heavy episodic drinking.
Epidemiological studies— These studies look at factors affecting the health and illness of populations.
Foie Gras— Liver of a duck or goose that has been specially fattened. It can be sold whole or prepared as pate or mousse.
High-density lipoprotein (HDL)— Often referred to as good cholesterol. This takes cholesterol away from the cells and back to the liver, where it’s broken down or excreted.
Homocysteine— This is an amino acid. High blood levels are now considered a risk factor for several diseases, including CHD.
Low-density lipoprotein (LDL)— Often referred to as bad cholesterol. It carries cholesterol from the liver to the cells and can cause harmful build-up of cholesterol.
Procyanidin— These are associated with flavanoid antioxidants derived from grape seed extract, grape skin and red wine. Like Quercetin and Resveratrol they have many health-promoting benefits.
Quercetin— A natural compound which belongs to a group of plant pigments called flavonoids that are largely responsible for the colours of many fruits, flowers, and vegetables. They have many health-promoting benefits that may protect against cancer and cardiovascular disease.
Resveratrol— A natural compound found in grapes, mulberries, peanuts and red wine that may protect against cancer and cardiovascular disease.
Vasodilator— A substance that causes blood vessels the body to become wider allowing the blood to flow more easily.
regular, moderate wine consumption. Those who drank wine daily had half the risk of dying compared with non-drinkers or consumers of other alcoholic beverages. The researchers suggested the antioxidants in red wine, such as tannins and flavonoids, were key factors in its protective effects. The 1980 Seven Countries Study (Yugoslavia, Italy, Greece, Finland, Netherlands, United States and Japan) compared the relationship between diet and other risk factors to the occurrence of CHD. High intakes of animal foods, with the exception of fish, were associated with higher CHD death rates. With its reliance on meat and butter fat and less on fruits, vegetables, legumes and grains, the 40-year Zutphen study, the Dutch arm of the Seven Countries Study, looked independently at the effect of wine consumption. Their conclusion, reported at the 2007 American Heart Association’s 47th Annual Conference on Cardiovascular Disease Epidemiology and Prevention, was ‘Drinking a little alcohol every day, especially wine, may be associated with an increase in life expectancy’.
More recent studies have also found that any alcohol is responsible for most of the cardio protective effects previously seen with wine. A 1994 study of British doctors and 2002 study of U. S. male doctors indicated that the lowest risk of death was associated with one to two alcoholic drinks of any type per day, but there was no benefit from additional drinks.
However, 20 years on, there is still no conclusive evidence as to why with a diet high in saturate fat the French live longer. The World Health Organization (WHO) states ‘There is convincing evidence that low to moderate alcohol intake reduces the risk of coronary heart disease’, but as of 2007, the French Paradox has not been tested by the gold standard of research, a controlled clinical study. Until then moderate alcohol intakes with food may be the key to the French Paradox.
Description
While the French diet includes high fat foods such as cheese, croissants, pastries, butter, sausages and cold cuts, it also contains other heart healthy foods, which have a beneficial effect.
Alcohol
Although the French drink more alcohol a year than the British, it is generally with a meal. Unlike the UK, binge drinking is a rarity. The French have a moderate consumption of 1–2 glasses of wine a day, which has shown to help reduce the risk of heart disease.
Fiber
The French eat two to three times more soluble fiber from pulses, such as beans and chickpeas, fruit and vegetables, whole grains and grain products than the English and Americans. Soluble fiber helps to lower cholesterol levels. In addition these foods are a good source of antioxidants, such as Quercetin also found in red wine, which may reduce oxidation of harmful low-density lipoproteins (LDL) that can cause atherosclerosis (hardening of the arteries).
Vegetable sources of protein
A diet rich in animal meat may result in high levels of homocysteine in the blood, which can lead to atherosclerosis. Low levels of folate are associated with high homocysteine levels—an independent risk factor for CHD especially in men. The French diet is high in legumes, fresh fruits and vegetables, especially dark-green leafy vegetables that are a rich source of folate or folic acid, a B vitamin. Their animal protein dishes are generally accompanied by generous salads and pulses are a large part of typical winter foods, such as soups and stews, which may help to control levels of homocysteine.
Unsaturate fat
Although the French diet is high in fat, it includes plenty of unsaturated fat like olive oil, olives and nuts, which help lower the level of harmful LDL cholesterol. Like red wine, peanuts also contain significant amounts of the heart healthy antioxidant Resveratrol. One ounce of peanuts contains approximately 73 micrograms of Resveratrol, while a glass of red wine contains 160 micrograms per 30 millilitres (ml).
Goose and duck fat
These fats are commonly used for cooking and to make pate or mousse,such as foie gras (goose or duck liver). Although high in fat, these fats have a nutritional composition closer to that of olive oil than butter or lard. Olive oil has about 76% monounsatu-rated fat and 15% saturated fat. Goose fat is 56% monounsaturated fat and 27% saturated fat while butter is only 33% monounsaturated fat and a huge 63% saturated fat. The benefit of monounsaturated fats is they lower total and LDL cholesterol without affecting beneficial high-density lipoprotein (HDL) cholesterol.
Portion sizes
The French may have a diet high in fat, but they eat fewer calories consequently are slimmer than Americans. 11% of the French are obese compared with 30% in the United States. Fat stimulates the release of chol-ecystokinin, a hormone that acts as a hunger suppressant and prevents over eating and snacking. In addition, portion sizes in France tend to be a third to a half of American portions. For example, in Paris a croissant weighs in at 30g, while in Philadelphia it is 60g.
Lifestyle
A 2004 survey completed by the French government’s Committee for Health Education (CFES) on French food and health showed that French eating habits have not really changed in the last 10 years. Most people in France still eat home-prepared meals, take their time eating and generally do not snack. Whereas in America snacking is a $30 billion industry.
However, the only justification for the lower CHD rates that has been most scientifically proven is the moderate consumption of wine with meals.
Function
There are several potential benefits of red wine in lowering CHD risk.
Red wine contains flavanoid antioxidants, Resveratrol and Quercetin, which help prevent the build-up of fatty deposits within the wall of the arteries. Both are found in the skin of red grapes. A 2006 study indicates that antioxidant, procyanidin, found in red wines from the South West of France, which has the lowest incidence of CHD in France, helps lower blood pressure and may account for the lower rates of heart disease.
Alcohol itself has been shown to raise good HDL cholesterol levels, but as of 2007, the exact mechanism is still unknown. HDL cholesterol helps to carry LDL cholesterol away from the walls of the arteries and back to the liver for reprocessing or excretion. This prevents build-up of cholesterol in the artery walls and protects against heart disease.
Alcohol also has the effect of decreasing thrombosis or blood-clotting .It decreases fibrinogen production, a blood-clotting enzyme, which reduces the stickiness of platelets. This reduces the incidence of clots, which may lead to a heart attack or stroke.
Benefits
Moderate consumption of alcohol can have health benefits other than reducing the risk for CHD.
In 1997, a study by the American Cancer Society found the risk of death of any cause was lower for those who had moderate intakes of alcohol compare to non-drinkers. It is thought that the amount of Resveratrol in 2-3 glasses of red wine helps to starve cancer cells by blocking a key protein that feeds them. France has relatively low rates of stomach and colon cancer and the second-lowest world incidence of heart disease after Japan. However, drinking more can lead to a greater risk of cancer.
Data from the third National Health and Nutrition Examination Survey Study (NHANES III) in 1999 showed that regular alcohol intakes lowered the risk for gallstones by 25% in both men and women.
Precautions
Individuals involved with activities that require attention, skill, or coordination, such as driving or operating machinery, should avoid alcoholic beverages. Alcohol has a depressant effect on the central nervous system and slows down brain function, which can affect judgment and emotions as well as behaviour.
The 2005 Centers for Disease Control and Prevention (CDC) guidelines advise women who may become pregnant or are pregnant not to drink. Moderate drinking during pregnancy may result in behavioural or neuro-cognitive problems in children.
There is conflicting advise on moderate alcohol or no alcohol with breast feeding. The American Academy of Paediatricians still recommends avoiding alcohol while breast-feeding. Alcohol can be passed on to the baby through the milk, which can affect the baby’s feeding, sleeping or digestion. Heavy alcohol intakes have also been shown to reduce lactation. The National Childbirth Trust and the Association of Breastfeeding Mothers in UK advocate similar advice. The recommendation is to allow sufficient time between drinking and breast-feeding so the mother can fully metabolise the alcohol.
Individuals taking prescription and over the counter medications also need to be aware of the potential interactions any of their medications may have with alcohol and should consult a doctor.
Risks
Higher intakes of alcohol drinking levels seem to offset the benefits of moderate drinking on CHD, by increasing risk of death from many other diseases.
Excessive intake of any kind of alcohol increases the risk of cancer of the mouth, oesophagus, stomach, liver, breast and colon. The Cancer Prevention Study in 2002 found that one drink or less in postmenopausal women increased the risk of death from breast cancer by 30%. They did not find an increased risk in pre-menopausal women.
Excessive alcohol can increase blood pressure, which increases the risk for CHD. Cutting back to moderate drinking can lower systolic blood pressure by up to 10mmHg.
According to a US study published in 2005, older men who drink more than the daily recommendations of alcohol may be more likely to suffer from a stroke.
Triglycerides are a type of fat found in food. High levels in the blood are associated with an increased risk if CHD and the liver make more triglycerides with excess alcohol, sugar and calories.
The risk of cirrhosis seems connected more with alcohol abuse than moderate use. Excessive drinkers will develop fatty liver, the first stage of alcoholic liver disease, but this can disappear when alcohol is reduced to moderate levels. Continued excessive alcohol can lead to alcoholic hepatitis or cirrhosis and liver failure.
Heavy alcohol use for 10 years or more is the usual cause of Chronic Pancreatitis. Acute pancreatitis with severe abdominal pain can occur before this and will settle if drinking is discontinued.
Research and general acceptance
There has never been a controlled clinical trial testing the effect of alcohol, but there is agreement that while drinking too much of any kind of alcohol is not healthy, moderate alcohol intakes may have some health benefits. As such, a number of medical associations including the European Society of Cardiology, The National Institute on Alcohol Abuse and Alcoholism, American Dietetic Association, American Heart Association, Royal College of Physicians, and British Heart Foundation have the recommendation for alcohol as ‘If you use alcohol, do so in moderation’. Recommendation on how many drinks per day equate moderation differs from country to country. In the United States, moderation is defined as up to one drink per day for women and up to two drinks per day for men. In the United Kingdom, moderation is defined as not exceeding 2–3 units for women and 3– 4 units for men. There is also agreement that the evidence is not convincing enough to make a recommendation to start drinking alcohol if teetotal.
However, Dr Malcolm law and Nicholas Wald, British specialists in preventive medicine at St. Bartholomew’s and the Royal London School of Medicine and Dentistry and Dr. Marion Nestle, chairwoman of the department of nutrition at New York University, have put forward another explanation for the French
QUESTIONS TO ASK YOUR DOCTOR
- What does moderate drinking mean?
- How much red wine should I be drinking?
- What health problems are associated with drinking?
- Can I drink when I am pregnant?
- What does one unit of alcohol include?
- Can I save all my daily alcohol units for the weekend?
diet and health. They argue that it is related to France’s history of lower animal fat intakes rather then their consumption of red wine. Up to 1970, the French ate less animal fat and had significantly lower blood cholesterol levels than the British. Now French habits are changing, they are eating more meat and fast foods and their consumption of animal fat is similar to those in Britain. The 1999 National Survey on Individual Food in France by the Research Center for the Study and Monitoring of Living Standards shows that between 1950 and 1980 the consumption of meat fat and oils doubled and alcohol intake halved. The rate of obesity in France has also increased from 8% in 1997 to 12% (The 2003 National Health and Wellness Survey by Consumer Health Sciences) and over 40% of the French are now considered overweight, not far off the 50% figure for the British and Americans. They say it takes 25-35 years for increased fat intakes to translate into heart disease and it is only a matter of time before France faces the obesity epidemics and CHD rates that began in America and Britain nearly 20 years ago.
Resources
BOOKS
Guiliano, Mireille. French Women Don’t Get Fat: The Secret of Eating for PleasureKnopf, 2004. A non-diet book on how to eat with balance, control and pleasure, including recipes.
Lewis, Perdue. The French Paradox and Beyond: Living Longer with Wine and the Mediterranean Lifestyle Renaissance Publishing, 1992.Backed by Dr. Curtis Ellison, Chief, Department of Preventive Medicine and Epidemiology, Boston University School of Medicine a supporter of the French Paradox, this book describes the benefits of the Mediterranean lifestyle.
Mayle, Peter. A Year in Provence Vintage Reprint edition, 1991 A light-hearted autobiography as well as a travel/ restaurant guide and cultural study of the south of France by a British businessman who gives Britain up it and buys ahouse in Provence with his wife and two dogs.
PERIODICALS
Boffetta P and Garefinkel L. ‘Alcohol drinking among men enrolled in an American Cancer Society prospective study’Epidemiology 1990, 1(5), 42–48.
Corder R, Mullen W, Khan NQ, MArks SC, Wood EG, Carrier MJ and Crozier A.‘Red wine procyanidins and vascular health’ Nature November 2006, 444,566.
Doll R, et al. ‘Mortality in relation to consumption of alcohol: 13 years observations on male British doctors’ British Medical Journal 1994, 309, 911–918.
Feigelson H‘Alcohol Consumption Increases The Risk Of Fatal Breast Cancer’ Cancer Causes and Control December 2002.
Gunzerath L, Faden V, Zakhari S, and Warren, K ‘National Institute on Alcohol Abuse and Alcoholism report on moderate drinking’ Alcoholism: Clinical & Experimental Research December, 2004 28(6) 829–847.
Keys A. ‘Coronary Heart Disease in Seven Countries’ Circulation 1970, 41(Suppl I):I-1–I-211.
Law M, Wald N. ‘Why heart disease mortality is low in France: the time lag explanation’ British Medical Journal 1999, 318:1471–1480.
McElduff P and Dobson AJ ‘How much alcohol and how often? Population based case-control study of alcohol consumption and risk of a major coronary event prospective study’ British Medical Journal 1997; 314: 1159.
Mukamal KJ, Ascherio A, Mittleman MA et al. ‘Alcohol and risk for ischemic stroke in men: the role of drinking patterns and usual beverage’Annals of Internal Medicine 2005,142:11–19.
Thun MJ, Peto R, Lopez AD, Monaco JH, Henley SJ, Heath CW and Doll R. ‘Alcohol consumption and mortality among middle-aged and elderly U.S. adults’ New England Journal of Medicine 1997, 337: 1705–1714.
ORGANIZATIONS
American Heart Association (AHA). National Center, 7272.
Greenville Avenue, Dallas, TX 7523 USA. Website: <http://www.americanheart.org/>
American Dietetic Association (ADA). 120 South Riverside Plaza, Suite 2000, Chicago, Illinois 60606-6995 USA. Website: <http://www.eatright.org/>
British Heart Foundation (BHF).14 Fitzhardinge Street, London W1H 6DH, UK. Website: <http://www.bhf.org.uk/>
European Society of Cardiology. The European Heart House, 2035 Route des Colles 2035 Route des Colles, B.P. 179 - Les Templiers, F-06903 Sophia Antipolis, France. Website:<http://www.escardio.org/>
Food Standards Agency UK (FSA). Eat well Be well, Healthy Heart Aviation House, 125 Kingsway, London WC2B 6NH UK. Website: <http://www.eatwell.gov.uk/> .
National Institute on Alcohol Abuse and Alcoholism (NIAAA). 5635 Fishers Lane, MSC 9304, Bethesda, MD 20892-9304 USA. Website: <http://www.niaaa.nih.gov/>
The Royal College of Physicians. 11 St Andrews Place, Regent’s Park, London, NW1 4LE uk. Website: <http://www.rcplondon.ac.uk/>
Tracy J Parker, RD.