name: | Neil Barnard |
section: | Nutrition |
for: | The Defence |
experience: | Preventative medicine |
summary:
As a result of their high content of fat and cholesterol, McDonald's products contribute to heart disease, certain forms of cancer, and other diseases. The links between high-fat diets and certain diseases are established beyond any reasonable doubt.
cv:
My name is Neal D. Bernard, M.D. I am a licensed physician, a graduate of the George Washington University School of Medicine, and a diplomat of the National Board of Medical Examiners. Since 1985, I have been President of the Physicians Committee for Responsible Medicine, a non-profit organization of more than 3,000 physicians in the United States.
I am the author of three books on nutrition and health, lecture frequently on the role of nutrition in preventive medicine, and am Editor-in-Chief of Good Medicine, a quarterly magazine on medical issues, including nutrition. In these capacities, I have extensively reviewed the medical literature on nutrition issues.
I understand the relevant issues raised in this case, and my comments are set out below.
Full cv:
Available for this witness
full statement:
Many products sold at McDonald's restaurants are high in fat and cholesterol, and low in fiber and certain vitamins. For example, according to Bowes and Church's Food Values of Portions Commonly Used (1989) by J.A.T. Pennington, 55% of the calories in a Big Mac come from fat, along with 83 mg of cholesterol. For a cheeseburger, fat content is 45%, with 41 mg of cholesterol. French fries are 47%, while a hamburger is 39% fat and holds 29 mg of cholesterol. Many other products sold by the restaurant chain are similarly high in fat and cholesterol. For comparison, beans are only 4% fat. Rice is 1-5% fat, depending on the variety. A potato is less than 1% fat.
As a result of their high content of fat and cholesterol, McDonald's products contribute to heart disease, certain forms of cancer, and other diseases. The links between high-fat diets and certain diseases are established beyond any reasonable doubt.
Beef, cheese, and other animal products contain two ingredients that increase cholesterol levels: cholesterol itself and saturated fat.
There are 100 milligrams of cholesterol in four ounces beef. Every 100 milligrams of cholesterol in one's daily diet adds roughly 5 mg/dl to the total cholesterol level of the average person.
The saturated fat in beef and cheese stimulates the liver to make more cholesterol. Meats have fat not only on the outer edge, but also marbled throughout the lean. Approximately fifty percent of beef fat is saturated, which is far higher than for vegetable oils.
McDonald's advertising has been misleading regarding its fat content. The company announced the arrival of the McLean Deluxe burger by claiming that it was 91 percent fat-free. McDonald's was reporting the fat content by weight. But when dietitians or scientists measure the fat content of foods, they are not interested in the percentage by weight, because water content strongly affects the measurements. The relevant measurement is the percentage of calories from fat. Using that standard, the McLean Deluxe burger patty is 49 percent fat, due to its main ingredient being ground beef. The bun and toppings dilute the burger down to 29 percent fat, but the nine percent figure is misleading.
On July 21, 1990, the medical journal, The Lancet, published the research findings of Dr. Dean Ornish the University of California at San Francisco showing that heart disease can actually be reversed in 82% of patients using a combined regimen of a vegetarian diet along with other lifestyle measures. (Ornish 1990).A diet containing lean meat has been demonstrated to make plaques worse over time. (Ornish 1990, Blankenhorn 1987, Brown 1990) A diet including food products such as those sold at McDonald's could not accomplish this result, and, instead, tends to encourage the progression of heart disease.
The prevalence of ischemic heart disease is markedly reduced in populations which avoid meat. Phillips (1978) found a positive history of heart disease in only 3.6 percent of vegetarians age 35-64, compared to 5.1 percent among omnivores. At age 65 and older, these figures became 16.2 and 19.1 percent, respectively.
Those who avoid meat products also have a reduced risk of heart disease mortality. A study of 10,943 Welsh health food store patrons compared vegetarians and nonvegetarians in this presumably health-conscious population, and also compared both groups to the general population. Standardized mortality ratios (SMR) for heart disease among nonsmokers after seven years were .36 for both male and female vegetarians, compared to .62 for nonvegetarian males and .41 for nonvegetarian females. (Burr 1982) After 10-12 years of follow-up, SMRs for heart disease were .43 among all vegetarians and .60 for all nonvegetarians in the health food store patron survey. (Burr 1988) An 11-year study of German vegetarians showed similar results, SMR's for cardiovascular morlality of .39 (men) and .46 (women). (Chang- Claude 1992) Conversely, Adventist omnivores were shown to have age-adjusted relative risks of fatal ischemic heart disease of 1.51 (men) and 1.37 (women), when followed for a 20-year period, compared to Adventist vegetarians (Snowdon, 1984).
The low rates of heart disease among those who avoid meat products, such as those products served at McDonald's, reflect their lower prevalence of risk factors, such as elevated serum cholesterol leevls, obesity, and high blood pressure. Several studies have shown that serum cholesterol levels are markedly lower in vegetarians. A study of 233 vegetarians, matched for place of residence, sex, age, marital status, height, weight, and occupation with nonvegetarians showed that the vegetarians' mean serum total cholesterol of 185 mg/dl was significantly less than that of the nonvegetarians, 196 mg/dl. HDL values were not reported. Some of the nonvegetarians ate meat infrequently. For those nonvegetarians who ate meat at least once per week, mean cholesterol level was 19 mg/dl higher than that of vegetarians. (West 1968)
Those who avoid meat products, such as those sold at McDonald's, have lower cholesterol levels than those who consume them. Sacks found the total and HDL cholesterol levels of lactovegetarians to be 161 mg/dl and 46 mg/dl (TC/HDL=3.5), respectively. For vegans, total and HDL cholesterol levels were 133 mg/dl and 43 mg/dl (TC/HDL=3.1). (Sacks 1985) In a group of young subjects (20-47 years of age), Fisher (1986) found the average total cholesterol of meat-eaters to be 172.9 mg/dl, and of vegetarians to be 140.1 mg/dl.
Comparisons of a group of vegans with omnivorous controls matched for age and sex showed marked differences in serum lipids between the two groups. In vegan subjects 20-30 years of age, total cholesterol and HDL were 125 and 37 (TC/HDL=3.4), respectively, for males, and 133 and 43 (TC/HDL=3.1) for females. Among controls, total cholesterol and HDL were 184 and 48 (TC/HDL=3.8) respectively, for males, and 174 and 50 (TC/HDL=3.5) for females. In older vegan subjects, 30-40 years of age, total cholesterol and HDL were 137 and 41 (TC/HDL=3.3), respectively, for males, and 147 and 44 (TC/HDL=3.3) for females. Among controls, total cholesterol and HDL were 196 and 46 (TC/HDL=4.3), respectively, for males, and 193 and 54 (TC/HDL=3.6) for females. (Burslem 1978)
Avoiding meat products, such as those sold at McDonald's, reduces cholesterol levels when adopted by previously omnivorous subjects. When a vegetarian diet omitting all animal products other than skim milk was followed for three weeks in 15 previously omnivorous young (mean age 28) health professionals and health students, total cholesterol and HDL dropped from 160.0 to 140.0 mg/dl (TC/HDL=4.2), and from 37.1 to 33.4 mg/dl (TC/HDL=4.3), respectively. (Cooper 1982) A trial of a lactoovovegetarian diet in men, ranging in age from 28 to 64 (mean 44) years, reduced total and HDL cholesterol from baseline levels of 235 mg/dl (6.07 mmol/l) and 56 mg/dl (1.46 mmol/l) to 210 mg/dl (5.43 mmol/1) and 53 mg/dl (1.36 mmol/l), respectively, in six weeks. The corresponding drop in TC/HDL ratio was 4.2 to 4.0. (Kestin 1989) A vegetarian diet, in which the only permitted animal products were egg whites and one-half cup of non-fat dairy products per day, and in which total tat was limited to 10 percent of calories was conduuted for one year in patients whose mean age was 57. The total cholesterol level dropped from 229 mg/dl to 178 mg/dl, while HDL changed slightly, from 38.8 mg/dl to 36.8 mg/dI. (Ornish 1990)
"Indeed, a comparison of populations indicates that death rates for cancers of the breast, colon, and prostate are directly proportional to estimated dietary fat intakes."
International comparisons have shown that fat in the diet, especially animal fat, increases the risk of breast cancer. (Armstrong 1975, Carroll 1985, Rose 1986) In Japan in the late 1940's, when breast cancer was particularly rare, only about seven percent of the calories in the Japanese diet came from fat, (Lands 1990) but Japanese women who eat meat daily have 8.5 times higher risk of breast cancer compared to women who rarely or never eat meat. (Hirayama 1978) As meat consumption has increased in post-World War II Japan, cancer rates are rising. Fat intake in Japan climbed fron nine percent of calories in 1955 to 25 percent in 1987. Breast cancer death rates are increasing steadily, along with cancer of the colon, ovary, uterus, prostate and pancreas. (Wynder 1991)
Paulo Toniolo, of the New York University Center, compared 250 women with breast cancer to 499 women without cancer from the same province in north-western Italy. The two groups ate about the same amount of olive oil and carbohydrates, but what made the cancer patients different was that they had habitually eaten more meat, cheese, butter, and milk. The women who consumed more animal products had as much as three times the cancer risk of other women. (Toniolo 1989)
Uterine cancer is also linked to fatty diets, as well an to obesity, which is more common on such diets. (Elwood 1977)
Ovarian cancer is also more common where people eat higher- fat diets. (Armstrong 1975, Lingeman 1974)
Cancer of the prostate is strongly linked to the consumption of meat and other animal products. (National Research Council 1982, Howell 1974, Blair 1978, Kolonel 1981, Rotkin 1977, Schuman 1982, Graham 1983, Ross 1987, Severson 1989, Oishi 1988, Mettlin 1989, Phillips 1975, Mills 1989)
Strong links have also been found between the consumption of meats and other fatty foods and colon cancer. (National Research Council 1982, Willett 1990, Gerhardason 1991) When the past diets of cancer patients are studied, it is clear that meat-based diets are linked to colon cancer. Meats contain a substantial amount of fat, and foster the growth of bacteria that cause carcinogenic secondary bile acids to form. In addition, when meat is cooked, carcinogens form on its surface.
Pancreatic cancer has also been linked to consumption of meat. (National Research Council 1982)
Avoiding meat products, such as those sold at McDonald's, improves the body's defenses against cancer. Researchers at the German Cancer Research Center in Heidelberg tested the strength of the immune systems of vegetarians. They took samples of their white blood cells and tested their capacity to destroy cancer cells (Malter 1989) The vegetarians were compared against non- vegetarians working at the cancer center. The results showed that vegetarians had more than double the ability of their non- vegetarian counterparts to destroy cancer cells.
Dietary fat also shortens the survival of patients diagnosed with cancer. In a Canadian research study, women with cancer were more likely to have lymph node involvement if they had a higher intake of saturated fat. (Verreault 1988) Researchers in Buffalo, New York, calculated the degree of risk posed by fat in the diet: For a woman who has breast cancer, her risk of dying from the disease at any point in time increases forty percent for every 1,000 grams of fat consumed monthly. (Gregorio 1985)
Cancer rates among those who avoid meat are far below population averages. A prospective German study of 1,904 subjects found standardized cancer mortality ratios for vegetarians, compared to nonvegetarians, of .48 for males and .74 for females. (Chang-Claude 1992) Lower than average standardized mortality ratios were found for colorectal, lung, breast, prostate, and other cancers.
In a study of 88,751 nurses, meat and animal fat were clearly correlated with colon cancer risk. Women who ate beef, pork, or lamb daily had a relative risk of colon cancer of 2.49, as compared to those who ate those products less than once a month. (Willett 1990) Fruit fiber had a non-significant negative association with colon cancer risk, and there was no demonstrable association between vegetable oils and cancer. Similarly, the risk of developing colon cancer for Adventists in the upper third of animal fat consumption (among Adventists) was 1.95 times the risk for those in the lowest third.
Lower colon cancer incidence rates in vegetarians have been attributed to lower levels of cholesterol and bile acids, particularly secondary bile acids, in their intestinal tracts. (Aries 1971, van Faassen 1987, Nair 1984, Turjman 1984, Reddy 1973) The ratio of secondary to primary bile acids is reduced as meat consumption is reduced (Turjman, 1984), at least in part due to favorable changes in the gut flora when vegetarian diets are adopted. (Aries 1971, van Fassen, 1987)
Lung cancer rates are significantly lower in vegetarian populations, even in studies which control for smoking. Among non-smokers, mortality ratios for Adventists, compared to non- Adventists, are .67 for men and .42 for women. (Phillips 1980b)
Avoidance of meat products and other fatty foods, such as those served at McDonald's, also reduces the risk of other serious illnesses, some of which are noted below:
Nearly 37% of nonvegetarians in one study had a history of physician-diagnosed hypertension, compared to 14.0 percent of vegetarians. Current use of antihypertensive medication was reported by 18.5 percent of nonvegetarians and 10 percent of vegetarians (Melby 1985) A similar study provided data for 264 white and 114 African-American vegetarians (defined as no consumption of meat, fish or poultry) and nonvegetarians, all of whom were non-smokers. The prevalence of hypertension requiring current medication use was 44 percent among African-American non-vegetarians, 18 percent among African-American vegetarians, 22 percent among white nonvegetarians, and 7 percent of white vegetarians. (Melby 1989)
Adjusting for body weight and age, a vegetarian diet is independently associated with 5 to 10 mmHg lower systolic blood pressure and 2 to 10 mmHg lower diastolic blood pressure, compared to omnivores (Rouse 1982, 1983; Sacks 1988).
A study controlled for age, sex, and body weight found that blood pressure in vegetarians is 6-9 mmHg lower (systolic) and 8-14 mmHg lower (diastolic), comparod to nonvegetarians. (Sacks 1988)
Comparison of vegetarians with omnivorous controls, adjusted for sex, age, height, and weight, revealed an average blood pressure for vegetarians of 128.7/76.2 mmHg, compared to the control mean value of 139.3/84.5 mmHg. The difference in systolic values was 10.6 mmHg and in diastolic was 8.3 mmHg. Adjusting for coffee and tea consumption did not affect the difference in systolic values, but diminished the difference in diastolic values to 4.7 mmHg. (Armstrong 1977)
Rouse (1982) compared vegetarian Adventists with non-vegetarian Mormons. Atter adjusting for age and body weight, blood pressure among vegetarians averaged six mmHg lower (diastolic) and three to six mmHg lower (diastolic). Mean blood pressure for vegetarian males was 115.6/68.7 mmHg, compared to 121.2/72.2 mmHg for omnivorous males. Mean blood pressure for vegetarian females was 109.1/66.7 mmHg, compared to 114.9/72.6 mmHg for omnivorous females.
The true effects of diet are greater than these numbers suggest. Adjusting for weight underestimates the effect of vegetarianism, because vegetarianism generally reduces body weight. For example, in a study comparing 48 vegetarians (mainly ovolactovegetarians) and 41 omnivores, not adjusted for body weight, the vegetarian's blood pressure was 110/73 mmHg, compared to the control value of 126/80 mmHg, resulting in differences of 16 mmHg systolic and 7 mmHg diastolic. (Ernst 1986)
The adoption of a vegetarian diet has been found to lower the blood pressure of normotensive or hypertensive omnivores. Normotensive volunteers who began an ovolactovegetarian diet for six weeks experienced average reductions in systolic blood pressure of 6.8 mmHg and in diastolic blood pressure of 2.7 mmHg. (Rouse 1983) Blood pressure changes were independent of age, sex, initial blood pressure, body mass index, and change in body weight. (Rouse 1986) Mildly hypertensive omnivores who adopted an ovolactovegetarian diet for six weeks demonstrated a reduction in systolic blood pressure of about 5 mmHg, independent of Sodium intake, but had no statistically significant change in diastolic blood pressure. (Margetts 1985, 1986)
Eliminating meats has also permitted hypertensive patients to eliminate medication use. In a one-year trial of a vegan diet, along with mild exercise (walking), of 26 patients who had been taking antihypertensive medication, 20 were able to discontinue all use of antihypertensive medications. The mean maximal blood pressure value prior to beginning medication was 198/115 mmHg. The mean blood pressure.on medication, but before beginning the vegan diet, was 151/88 mmHg. The mean blood pressure after 12 months on the vegan diet, and after 20 of the patients had discontinued medication, was 142/83 mmHg. (Lindahl 1984)
No single nutrient or group of nutrients has been identified that, by its presence or absence, accounts for the blood pressure lowering effect of a vegetarian diet. (Armstrong 1979, Rouse 1984, Sacks 1988)
Overall, Seventh-day Adventists, about half of whom are vegetarians, have 45 percent of the rate of diabetes of the general population, and within the Adventist population, vegetarians have lower rates of diabetes than nonvegetatarians. In a large prospective study of Adventists, the prevalence of diagnosed diabetes at the outset was 1.9 times higher in nonvegetarian men and 1.4 times in nonvegetarian women, compared to vegetarians. Excluding those with diabetes at the outset, the remaining subjects were followed over the subsequent 21 years. Among this group, the age-adjusted risk of diabetes appearing on a death certificate for nonvegetarians, compared to vegetarians was 2.2 for men and 1.4 for women. Adjusting for weight, the prevalence of diabetes at the outset of this study was 1.8 times higher in nonvegetarian men and 1.4 times higher in non-vegetarian women, compared to vegetarians, and the risk of diabetes appearing on a death certificate for those who were not diabetic at the outset was 1.8 for nonvegetarian men and 1.1 for nonvegetarian women. (Snowdon, 1985)
Diets restricting meat consumption have also been shown to improve diabetic control. In a study of 65 patients (42 men, 27 women) with non-insulin-dependent diabetes, aged 35-82 years (average 61.5), a 26-day inpatient program used a diet composed of grains, vegetables, fruits, and legumes, and limiting meats to 85 grams per week and limiting dairy use to non-fat products only, along with mild exercise. At the end of 26 days the average fasting glucose level dropped from 179.5 to 133.5 mg/dl. Medication use was greatly reduced, and remained so thereafter. A follow-up 2-3 years later, the number of patients on insulin had dropped from 18 at baseline to 10; the number on oral medication dropped from 31 at baseline to 13, and the number controlled with diet alone increased from 20 to 46. In the 2-3 year follow-up period, 15 patients had a total of 17 hospitalizations. (Barnard, 1983)
In a 25-day inpatient program, researchers used a low-fat, vegetarian diet. with regular exercise in patients with diabetic neuropathy. Patients ranged in age from 45 to 78 (average 64). Of the 22 patients, 17 had a remission of pain in 4-16 days (average 10.3), accompanied by a drop in average fasting blood sugar from 169 to 121. Six subjects stopped insulin or oral medications. At follow-up one to four years later, 17 of the 21 patients remained on the prescribed regimen, of whom 16 retained the gains they achieved in the inpatient program. (Crane)
The diets of patients who tend to stay free of retinal damage are higher in carbohydrate and fiber, and lower in protetin. (Roy, 1989)
In international comparisons, the prevalence of diabetes correlates positively with obesity, serum cholesterol levels, and intake of fat, animal fat, protein, animal protein, and sugar, and correlates negatively with intakes of carbohydrate and vegetable fat. (West 1966, 1971) Saturated fat consumption may increase insulin secretion and lead to insulin insensitivity. it may also alter fecal microbial enzyme activity and increase estrogen synthesis, which in turn reduces insulin sensitivity. (Snowdon, 1985) High-fiber diets lower post-prandial blood sugars and insulin levels, due to both delayed gastrointestinal absorption of glucose and increased tissue sensitivity to insulin. (Munoz, 1984) Vegetarian diets are low in cholesterol and fat, particularly saturated fat, and high in complex carbohydrates and fiber.
The McDonald's Corporation aggressively aims promotions at children, using the Ronald McDonald character, Saturday morning advertising, popular movie themes, and bright, attractive play areas at each store.
During March, 1993, (National Nutrition Month), McDonald's distributed attractive plastic toys and booklets on what the restaurant chain considers to be good nutrition. One of these toys is a plastic beef steak named "Slugger," which flexes its toy muscles as if to suggest that meat gives strength. The accompanying booklet states that eating two servings a day of foods in the meat group "can make it easier to do things like climb higher and ride your bike farther." The meat group includes beef, pork, poultry, fish, and also eggs, beans, and nuts.
Foods in the meat group do not increase endurance or athletic prowess, and do not improve a child's capacity to climb or ride a bike. The concept that high-protein foods are essential for endurance was proved false many years ago, as noted in the American Journal of Nutrition
"During the mid-1800's Liebig, the preeminent physiological chemist of his time, promoted the concept that energy for all muscular movement was produced by the oxidation of protein. The customary diets of heavy laborers and athletes were found to be high in protein, and this was accepted as a physical necessity.... Although research of the 1850s and 1860s soon showed that Liebig's theory was false, and that carbohydrates and fatty acids were the major fuels of muscular activity, Liebig's writings had a continuing impact well into the 20th century." - (Nieman 1988).
It is now well established that carbohydrate, stored in the form of glycogen, is the limiting factor in endurance. The practice of 'carbo-loading" is a common practice among endurance athletes. While beans and nuts do contain carbohydrate, the principal members of the "meat group" are devoid of carbohydrate, being principally composed of protein and fat. There is no evidence whatsoever that such foods improve athletic performance for children or adults.
In the period immediately following a meal, meats can cause a measurable increase in blood viscosity, something which, if anything, will impair athletic performance.
The Physicians Committee for Responsible Medicine has asked the Office of Advertising Practices of the Federal Trade Commission to direct McDonald's to halt this promotional campaign. The statement that meat or related products "can make it easier to do things like climb higher and ride your bike farther" is a false claim and should be withdrawn. An accurate description of the effects of meat consumption would note its links to heart disease, cancer (particularly colon and prostate cancer), obesity, and other health problems.
As the director of the Framingham Heart Study Dr. William Castelli, has said: "When you see the golden arches, you're probably on the road to the pearly gates."
supplementary statement:
Fat, Cholesterol and Heart Disease
McDonald's products tend to be high in fat and cholesterol.
Diets that are high in fat and cholesterol increase the risk of
coronary heart disease (CHD). This is of grave concern because
heart disease is very common in the U.K., the U.S., and other
Western countries. An estimated 6,160,000 Americans had coronary heart disease in 1992, defined as angina pectoris (chest pain) and/or a history of heart attack. The epidemic is not limited to older individuals; about 45 percent of the 1,500,000 Americans who have heart attacks each year are under age 65.(1)
The effects of dietary cholesterol and dietary fat can be separated for purposes of discussion, although many McDonald's products contain substantial amounts of both. Dietary Cholesterol
According to Bowes and Church's Food Values of Portions Commonly Used (1989) by J.A.T. Pennington, a Big Mac contains 83mg of cholesterol, a cheeseburger contains 41 mg of cholesterol, and a hamburger holds 29 mg of cholesterol. The mathematical relationship between dietary cholesterol and heart disease was summarized in an American Medical Association journal, called the Archives of Pathology and Laboratory Medicine, in October, 1988, by Jeremiah Stamler, M.D., of Northwestern University Medical School in Chicago, Illinois, and Richard Shekelle, Ph.D., of the University of Texas School of Public Health in Houston, Texas:
"In humans, ingestion of dietary cholesterol raises serum cholesterol, largely through its effect on low-density lipoprotein-cholesterol. Over the range of intake in usual American diets, this effect is substantial, e.g. with 300 mg of cholesterol intake per 1,000 kcal, rather than 100, serum cholesterol is on average about 6% to 7% higher, equivalent to a 12% to 14% greater risk of coronary heart disease."(2)
The Lipid Research Clinics Trial, one of the best-known multi-center research studies on heart disease, showed that on average every one percent increase in the serum cholesterol level is associated with an increase in the risk of a heart attack of two percent or more.(3) The relationships between dietary cholesterol and cholesterol levels, and between cholesterol levels and heart disease risk, as I have described them here, are commonly accepted by researchers and clinicians.
Dietary cholesterol also contributes to heart disease apart from its effect on serum cholesterol levels, as the article by Stamler and Shekelle describes:
"In addition, since 1981, four prospective within-population studies have shown that dietary cholesterol intake of individuals is significantly related to their long-term CHD risk, independent of and in addition to serum cholesterol, blood pressure, and cigarette use. On average, a 200 mg/1000 kcal higher intake of cholesterol at baseline was associated with a 30% higher CHD rate (95% confidence interval, 1.1 to 1.5). Conversely, lower intakes of cholesterol were associated with significantly lower risks of CHD, and of all causes mortality as well....The importance of a low-dietary cholesterol intake for prevention of CHD merits emphasis."(2)
There is no reasonable doubt that dietary cholesterol increases the risk of heart disease and that foods of the type sold at McDonald's contain sufficient cholesterol to present a genuine risk.
Dietary Fat
Animal fats are particularly rich in saturated fatty acids
(SFA). Approximately fifty percent of beef fat is saturated.
Bowes and Church's Food Values of Portions Commonly Used (1989) reports that fat contributes 55% of the calories in a Big Mac, 45% of the calories of a cheeseburger, 47% of the calories of
McDonald's french fries, and 39% of the calories in a hamburger.
Saturated fat tends to increase serum cholesterol levels
through its effect on the liver. The relationship between saturated fat intake and total cholesterol (total-C) levels was
summarized in an article drafted by scientists with the National
Cholesterol Education Program, published in the Journal of the
American Dietetic Association in 1988:
"...for every 1% increase in the SFA intake (on a caloric basis), plasma total-C increases approximately 2.7 mg/dL."(4)This means that for an average person with a cholesterol level of roughly 200 mg/dL, every one percent increase in saturated fat intake would then be associated with more than a one percent rise in plasma cholesterol which, as noted above, is associated with at least a two percent increased risk of heart disease. This effect of each percentage point increase in dietary fat must be added to the effect of the dietary cholesterol which is often part of fatty foods. Together, the effect on risk is substantial.
To put these figures in perspective, the average fat intake in the U.S. is approximately 37% of calories. As noted by Professor D.J. Naismith, the fat content of a typical McDonald's meal is substantially higher than that figure, at 43 percent. A typical McDonald's meal, of course, contains both cholesterol and fat.
The appropriate yardstick by which to judge foods of the type sold at McDonald's and their contribution to health risks is not the average American diet, but the dietary guidelines recommended by health authorities. The U.S. government and most major private health organizations have for many years recommended limiting dietary fat intake to less than 30 percent of calories. If anything, this figure is overly generous. International comparisons, such as those from various sections of China, clearly show advantages to reducing fat intake to levels that are substantially lower than those currently recommended by U.S. health authorities. Those advantages include a reduced risk of heart disease and cancer.
Diet and Cancer Risk:
In addition to the extensive information I have already
submitted regarding the links between foods of the type sold at
McDonald's and cancer risk, I would like to provide a few additional comments. These particularly relate to Professor Naismith's reference to cohort studies.
Cancer remains a serious and growing problem, and there is
no question that diet plays a substantial role in cancer risk.
More than 1.2 million Americans are diagnosed with cancer (excluding basal and squamous cell skin cancers and in situ carcinomas except bladder) annually, and more than 500,000 die of the
disease, accounting for one in every five deaths in the U.S.(5)
The most common forms of cancer in the United States are prostate, breast, lung, and colorectal.
As noted in my testimony, international and case-control studies have shown a strong relationship between fat intake and breast cancer risk, while most cohort studies have not shown a relationship. This same observation was recently made by Hunter et al. in the New England Journal of Medicine.(6) This observation is not new; rather it reflects the limitations of cohort studies. First, they have typically investigated only a narrow band of fat intake. Second, they do not generally account for fat intake during adolescence, which may be the time when fat exerts its greatest effect on breast cancer risk. Third, their follow-up periods are typically short.
It has long been apparent that a substantial portion of the risk for other cancers is attributable to dietary factors.(7) Colorectal cancer, for example, is diagnosed in 152,000 Americans and kills 57,000 annually.(5) Women and men who consume meat frequently have 2.5 and 3.6 times the incidence of colon cancer, respectively, compared to those who consume these products rarely or never.(8-11) The elevated colon cancer risk from diets high in animal products is believed to be caused by the higher levels of cholesterol and bile acids, particularly secondary bile acids, that these products cause in the intestinal tract.(12-16) Medical consensus holds that an increased consumption of high-fat, low-fiber foods affects the composition of the diet in such a way that there is a very real risk of cancer of the breast or bowel or heart disease as a result. When the dietary composition is altered in this way, it adds a very real risk of obesity, which, in turn, increases the risk of breast cancer and coronary heart disease; such increased risk is established beyond any scientific doubt.
date signed: | July 27, 1993 |
status: | ? |
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