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The Truth About Saturated Fat

By Mary Enig, PhD, and Sally Fallon

The Lipid Hypothesis
The theory—called the lipid hypothesis—that there is a direct
relationship between the amount of saturated fat and cholesterol in
the diet and the incidence of coronary heart disease was proposed by a
researcher named Ancel Keys in the late 1950's. Numerous subsequent
studies have questioned his data and conclusions. Nevertheless, Keys'
articles received far more publicity than those presenting alternate
views. The vegetable oil and food processing industries, the main
beneficiaries of any research that found fault with competing
traditional foods, began promoting and funding further research
designed to support the lipid hypothesis.
The most well-known advocate of the lowfat diet was Nathan Pritikin.
Actually, Pritikin advocated elimination of sugar, white flour and all
processed foods from the diet and recommended the use of fresh raw
foods, whole grains and a strenuous exercise program; but it was the
lowfat aspects of his regime that received the most attention in the
media. Adherents found that they lost weight and that their blood
cholesterol levels and blood pressure declined. The success of the
Pritikin diet was probably due to a number of factors having nothing
to do with reduction in dietary fat—weight loss alone, for example,
will precipitate a reduction in blood cholesterol levels—but Pritikin
soon found that the fat-free diet presented many problems, not the
least of which was the fact that people just could not stay on it.
Those who possessed enough will power to remain fat-free for any
length of time developed a variety of health problems including low
energy, difficulty in concentration, depression, weight gain and
mineral deficiencies.1 Pritikin may have saved himself from heart
disease but his lowfat diet did not spare him from cancer. He died, in
the prime of life, of suicide when he realized that his Spartan regime
was not curing his leukemia. We shouldn't have to die of either heart
disease or cancer—or consume a diet that makes us depressed.
When problems with the no-fat regime became apparent, Pritikin
introduced a small amount of fat from vegetable sources into his diet—
something like 10%% of the total caloric intake. Today the Diet
Dictocrats advise us to limit fats to 25-30%% of the caloric intake,
which is about 2 1/2 ounces or 5 tablespoons per day for a diet of
2400 calories. A careful reckoning of fat intake and avoidance of
animal fats, they say, is the key to perfect health.
The "Evidence" Supporting the Lipid Hypothesis
These "experts" assure us that the lipid hypothesis is backed by
incontrovertible scientific proof. Most people would be surprised to
learn that there is, in fact, very little evidence to support the
contention that a diet low in cholesterol and saturated fat actually
reduces death from heart disease or in any way increases one's life
span. Consider the following:
Before 1920 coronary heart disease was rare in America; so rare that
when a young internist named Paul Dudley White introduced the German
electrocardiograph to his colleagues at Harvard University, they
advised him to concentrate on a more profitable branch of medicine.
The new machine revealed the presence of arterial blockages, thus
permitting early diagnosis of coronary heart disease. But in those
days clogged arteries were a medical rarity, and White had to search
for patients who could benefit from his new technology. During the
next forty years, however, the incidence of coronary heart disease
rose dramatically, so much so that by the mid fifties heart disease
was the leading cause of death among Americans. Today heart disease
causes at least 40%% of all US deaths. If, as we have been told, heart
disease results from the consumption of saturated fats, one would
expect to find a corresponding increase in animal fat in the American
diet. Actually, the reverse is true. During the sixty-year period from
1910 to 1970, the proportion of traditional animal fat in the American
diet declined from 83%% to 62%%, and butter consumption plummeted from
eighteen pounds per person per year to four. During the past eighty
years, dietary cholesterol intake has increased only 1%%. During the
same period the percentage of dietary vegetable oils in the form of
margarine, shortening and refined oils increased about 400%% while the
consumption of sugar and processed foods increased about 60%%.2
The Framingham Heart Study is often cited as proof of the lipid
hypothesis. This study began in 1948 and involved some 6,000 people
from the town of Framingham, Massachusetts. Two groups were compared
at five-year intervals—those who consumed little cholesterol and
saturated fat and those who consumed large amounts. After 40 years,
the director of this study had to admit: "In Framingham, Mass, the
more saturated fat one ate, the more cholesterol one ate, the more
calories one ate, the lower the person's serum cholesterol. . . we
found that the people who ate the most cholesterol, ate the most
saturated fat, ate the most calories, weighed the least and were the
most physically active."3 The study did show that those who weighed
more and had abnormally high blood cholesterol levels were slightly
more at risk for future heart disease; but weight gain and cholesterol
levels had an inverse correlation with fat and cholesterol intake in
the diet.4
In a multi-year British study involving several thousand men, half
were asked to reduce saturated fat and cholesterol in their diets, to
stop smoking and to increase the amounts of unsaturated oils such as
margarine and vegetable oils. After one year, those on the "good" diet
had 100%% more deaths than those on the "bad" diet, in spite of the
fact that those men on the "bad" diet continued to smoke! But in
describing the study, the author ignored these results in favor of the
politically correct conclusion: "The implication for public health
policy in the U.K. is that a preventive programme such as we evaluated
in this trial is probably effective. . . ."5
The U.S. Multiple Risk Factor Intervention Trial, (MRFIT) sponsored by
the National Heart, Lung and Blood Institute, compared mortality rates
and eating habits of over 12,000 men. Those with "good" dietary habits
(reduced saturated fat and cholesterol, reduced smoking, etc.) showed
a marginal reduction in total coronary heart disease, but their
overall mortality from all causes was higher. Similar results have
been obtained in several other studies. The few studies that indicate
a correlation between fat reduction and a decrease in coronary heart
disease mortality also document a concurrent increase in deaths from
cancer, brain hemorrhage, suicide and violent death.6
The Lipid Research Clinics Coronary Primary Prevention Trial (LRC-
CPPT), which cost 150 million dollars, is the study most often cited
by the experts to justify lowfat diets. Actually, dietary cholesterol
and saturated fat were not tested in this study as all subjects were
given a low-cholesterol, low-saturated-fat diet. Instead, the study
tested the effects of a cholesterol-lowering drug. Their statistical
analysis of the results implied a 24%% reduction in the rate of
coronary heart disease in the group taking the drug compared with the
placebo group; however, nonheart disease deaths in the drug group
increased—deaths from cancer, stroke, violence and suicide.7 Even the
conclusion that lowering cholesterol reduces heart disease is suspect.
Independent researchers who tabulated the results of this study found
no significant statistical difference in coronary heart disease death
rates between the two groups.8 However, both the popular press and
medical journals touted the LRC-CPPT as the long-sought proof that
animal fats are the cause of heart disease, America's number one
killer.
Studies that Challenge the Lipid Hypothesis
While it is true that researchers have induced heart disease in some
animals by giving them extremely large dosages of oxidized or rancid
cholesterol—amounts ten times that found in the ordinary human diet—
several population studies squarely contradict the cholesterol-heart
disease connection. A survey of 1700 patients with hardening of the
arteries, conducted by the famous heart surgeon Michael DeBakey, found
no relationship between the level of cholesterol in the blood and the
incidence of atherosclerosis.9 A survey of South Carolina adults found
no correlation of blood cholesterol levels with "bad" dietary habits,
such as use of red meat, animal fats, fried foods, butter, eggs, whole
milk, bacon, sausage and cheese.10 A Medical Research Council survey
showed that men eating butter ran half the risk of developing heart
disease as those using margarine.11
Mother's milk provides a higher proportion of cholesterol than almost
any other food. It also contains over 50%% of its calories as fat, much
of it saturated fat. Both cholesterol and saturated fat are essential
for growth in babies and children, especially the development of the
brain.12 Yet, the American Heart Association is now recommending a low-
cholesterol, lowfat diet for children! Commercial formulas are low in
saturated fats and soy formulas are devoid of cholesterol. A recent
study linked lowfat diets with failure to thrive in children.13
Numerous surveys of traditional populations have yielded information
that is an embarrassment to the Diet Dictocrats. For example, a study
comparing Jews when they lived in Yemen, whose diets contained fats
solely of animal origin, to Yemenite Jews living in Israel, whose
diets contained margarine and vegetable oils, revealed little heart
disease or diabetes in the former group but high levels of both
diseases in the latter.14 (The study also noted that the Yemenite Jews
consumed no sugar but those in Israel consumed sugar in amounts
equaling 25-30%% of total carbohydrate intake.) A comparison of
populations in northern and southern India revealed a similar pattern.
People in northern India consume 17 times more animal fat but have an
incidence of coronary heart disease seven times lower than people in
southern India.15 The Masai and kindred tribes of Africa subsist
largely on milk, blood and beef. They are free from coronary heart
disease and have excellent blood cholesterol levels.16 Eskimos eat
liberally of animal fats from fish and marine animals. On their native
diet they are free of disease and exceptionally hardy.17 An extensive
study of diet and disease patterns in China found that the region in
which the populace consumes large amounts of whole milk had half the
rate of heart disease as several districts in which only small amounts
of animal products are consumed.18 Several Mediterranean societies
have low rates of heart disease even though fat—including highly
saturated fat from lamb, sausage and goat cheese—comprises up to 70%%
of their caloric intake. The inhabitants of Crete, for example, are
remarkable for their good health and longevity.19 A study of Puerto
Ricans revealed that, although they consume large amounts of animal
fat, they have a very low incidence of colon and breast cancer.20 A
study of the long-lived inhabitants of Soviet Georgia revealed that
those who eat the most fatty meat live the longest.21 In Okinawa,
where the average life span for women is 84 years—longer than in Japan—
the inhabitants eat generous amounts of pork and seafood and do all
their cooking in lard.22 None of these studies is mentioned by those
urging restriction of saturated fats.
The relative good health of the Japanese, who have the longest life
span of any nation in the world, is generally attributed to a lowfat
diet. Although the Japanese eat few dairy fats, the notion that their
diet is low in fat is a myth; rather, it contains moderate amounts of
animal fats from eggs, pork, chicken, beef, seafood and organ meats.
With their fondness for shellfish and fish broth, eaten on a daily
basis, the Japanese probably consume more cholesterol than most
Americans. What they do not consume is a lot of vegetable oil, white
flour or processed food (although they do eat white rice.) The life
span of the Japanese has increased since World War II with an increase
in animal fat and protein in the diet.23 Those who point to Japanese
statistics to promote the lowfat diet fail to mention that the Swiss
live almost as long on one of the fattiest diets in the world. Tied
for third in the longevity stakes are Austria and Greece—both with
high-fat diets.24
As a final example, let us consider the French. Anyone who has eaten
his way across France has observed that the French diet is just loaded
with saturated fats in the form of butter, eggs, cheese, cream, liver,
meats and rich patés. Yet the French have a lower rate of coronary
heart disease than many other western countries. In the United States,
315 of every 100,000 middle-aged men die of heart attacks each year;
in France the rate is 145 per 100,000. In the Gascony region, where
goose and duck liver form a staple of the diet, this rate is a
remarkably low 80 per 100,000.25 This phenomenon has recently gained
international attention as the French Paradox. (The French do suffer
from many degenerative diseases, however. They eat large amounts of
sugar and white flour and in recent years have succumbed to the
timesaving temptations of processed foods.)
A chorus of establishment voices, including the American Cancer
Society, the National Cancer Institute and the Senate Committee on
Nutrition and Human Needs, claims that animal fat is linked not only
with heart disease but also with cancers of various types. Yet when
researchers from the University of Maryland analyzed the data they
used to make such claims, they found that vegetable fat consumption
was correlated with cancer and animal fat was not.26