For a half century the idea
that saturated fat in foods raises cholesterol and, consequently,
causes heart attacks was dogma ostensibly justifying government
regulation. The attacks on dietary fat have increased in recent
years due to the “war on obesity.” But a new book based on
nearly ten years of research has fired a devastating salvo in defense
of this designated dietary enemy. The Big Fat Surprise: Why
Butter, Meat and Cheese Belong in a Healthy Diet by Nina
Teicholz traces the origin of the fat myth from its faulty scientific
beginning to its discrediting.
Teicholz notes the Inuit
people in the Arctic, who got 70 – 80% of their calories from fat
and ate no plants, showed no signs of cancer, diabetes, heart disease
or hypertension. In another intriguing study Maasai warriors in
Kenya, who ate only blood, meat and milk when they were studied in
early the 1960s, had no heart disease or high cholesterol.
The alarming myth about fat
was originated by Dr. Ancel Keys, for which he was even honored by
being on the cover of Time magazine
in 1961. That was the year he landed a position on the nutrition
committee of the American Heart Association, the same year the AHA
issued the first guidelines targeting saturated fats. Keys violated several
scientific norms in his research, but some of
these weren't revealed until 2002 by later researchers. It turns out
that from the 655 men he originally selected as a representative
sample, he used just 33 from Crete and 34 from Corfu as the basis for
the entire revolution of our diet. He also kept to himself for 16
years the results of a 9,000-patient coronary survey because it
failed to find cutting saturated fat reduced the risk of heart
disease. Though advocating limiting a diet to 7% saturated fat, Keys
ate chops, roasts and steaks three time a week and lived to be 100.
While our ingestion of saturated fats has dropped 11% since the early 1970s, we eat at least 25% more carbohydrates—including 50% more grains. Teicholz explains:
While our ingestion of saturated fats has dropped 11% since the early 1970s, we eat at least 25% more carbohydrates—including 50% more grains. Teicholz explains:
Instead of meat, eggs and cheese, we're eating more
pasta, grains, fruit and starchy vegetables...The problem is that
carbohydrates break down into glucose, which causes the body to
release insulin—a hormone that is fantastically efficient at
storing fat. Meanwhile, fructose, the main sugar in fruit, causes
the liver to generate triglycerides and other lipids in the blood
that are altogether bad news. Excessive carbohydrates lead not only
to obesity but also, over time, to Type 2 diabetes and, very likely,
heart disease
In 1961 the AHA advised switching to vegetable oils for
a “healthy heart.” Today these oils are 7% to 8% of our daily
calories, compared to nearly zero in 1900. But these were found to
create not only higher cancer rates but gallstones. It was also
known since the 1940s that when heated, vegetable oils create
oxidation products that lead to cirrhosis of the liver and early
death in animal experiments. To counter these concerns, vegetable
oils were hydrogenated, a process of adding hydrogen that turns the
oils from liquids into solids and also retards spoilage.
Unfortunately, hydrogenation also produced trans fats,
which were condemned by the FDA and many European countries for
raising the levels of “bad” LDL cholesterol. This led some
restaurants and food manufacturers to return to using liquid oils,
which had long-standing problems with oxidation. Worse, more recent
research had implicated oxidation in a “sizable body of
evidence...to heart disease and other illnesses such as Alzheimer's.”
In addition to
Teicholz's work, researchers
at
Purdue University studied the relationship between fats and
absorption of carotenoids, such as lutein, lycopene and
beta-carotene. These are disease-fighting nutrients that slash the
risk of cancer and heart disease, safeguard bone density, prevent
macular degeneration, and soak up damaging compounds. The
researchers served veggie salads topped with various types of salad
dressing to participants who were then tested for absorption of
carotenoids. Result: salads with the most fat—20 grams—yielded
the highest absorption of these nutrients. This study was not just
of saturated fats but included monounsaturated fats and
polyunsaturated fats. Canola oil (a monounsaturated oil) had the
best absorption rates of lutein and beta-carotene, but the
researchers said the type
of oil “had less impact on the absorption of carotenoids than
amount.”
So it's about time for the myths about fats, particularly saturated
fats, to die—and also the myths about government regulation of our
foods being necessary and effective. How could the U.S. government
be so wrong about such a major issue for a half century? Teicholz
notes that problems with vegetable oils were known back in the 1940s;
that Keys' research had major errors; that a half-dozen large
important trials from the 1970s had major methodological problems and
were “unreliable at best;” and “even back then, other
scientists were warning about the [Keys] diet's potential unintended
consequences.
After the American Heart Association targeted saturated fats, the
USDA apparently accepted the AHA's recommendation without examining
the validity of Keys' research—for which he had received a massive grant from the U.S.
government—or other dubious research. It also ignored the skeptics' warnings from, among others, the National Academy of Sciences.
Keys himself was likely instrumental in the U.S. Department of Agriculture's approval in 1980 because of his governmental connections. Teicholz notes he had quickly developed important alliances with the National Institutes of Health, politicians on Capitol Hill, and the USDA itself. Harvard professor Mark Hegsted successfully persuaded the U.S. Senate to recommend Keys' diet to the entire nation. In 1977 he said the question wasn't whether Americans should change their diet, but why not? He told the Senate no risks could be identified. In a nutshell, that's how bad science became bad federal policy for a half century.
Keys himself was likely instrumental in the U.S. Department of Agriculture's approval in 1980 because of his governmental connections. Teicholz notes he had quickly developed important alliances with the National Institutes of Health, politicians on Capitol Hill, and the USDA itself. Harvard professor Mark Hegsted successfully persuaded the U.S. Senate to recommend Keys' diet to the entire nation. In 1977 he said the question wasn't whether Americans should change their diet, but why not? He told the Senate no risks could be identified. In a nutshell, that's how bad science became bad federal policy for a half century.
Obviously, the American people would have been better off if the
government had never gotten into this issue. And it never should
have because there is nothing in the U.S. Constitution that gives the
federal government any authority over food. Franklin Roosevelt's
administration attempted to control agriculture with its Agricultural
Adjustment Act, under the Constitution's “general welfare”
clause, but the Supreme Court struck that down. A second attempt was
made under the federal power to regulate interstate commerce. In
Wickard v. Filburn, a farmer had planted 23 acres of wheat
although the government had allotted him only eleven. He was fined
for growing the excess even though the grain was never marketed. It
was consumed by livestock on his own property. There was no
commerce, much less interstate commerce. Yet the Supreme Court ruled
that if he had not fed the wheat to his stock, he might had
bought feed, and that feed, even if locally produced, might
have affected the price of other wheat in interstate commerce.
Therefore, the federal government's intervention in agriculture here
was “justified” by its authority to regulate interstate commerce.
That farfetched, contorted decision was the basis for subsequent
expansion of the USDA into food and nutrition programs, such as
school lunches and food stamps. Furthermore, that empowerment was
not limited to the USDA but extended to other federal agencies.
According to the Government Accountability Office, the federal
government in 2009 had six different agencies operating “about”
26 separate food and nutrition programs in the U.S.
In our next posting we shall discuss how, just as with fats,
government policies on school lunches are based on bad science and
have led to inferior nutrition. The nation would have been
healthier without these programs, but the myth still persists that they
are necessary and generally effective. Major mistakes—even those
enduring for decades—are dismissed as rarities or inconsequential when policies and
programs are determined by good intentions rather than principles or
actual results. As Milton Friedman
pointed out, “Underlying
most arguments against the free market is a lack of belief in freedom
itself.” It always seems to be a winning argument—though
unjustified by results—that somehow government coercion in the
economy will be more effective than its absence. And if that doesn't
work, just try more of the same: bigger programs, more
government-sponsored research, larger penalties for violations, etc.,
all in the name of “better” regulation. In truth, the solution
is not a “better” government economic program but none at all.
The best outcome results from people freely exercising their rights
to life, liberty and property and not being forced by government to
do anything. It's where all interactions are by mutual consent to
mutual benefit. That is the only economic principle appropriate for
a nation of free people. It is the only system consistent with the
principle of liberty. That's why when our Founders wrote the
Constitution, they did not delegate any economic authority to the
federal government.
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