Real Food (30 page)

Although Keys was a central figure in the cholesterol hypothesis, he was not always invited to mingle with the nutrition establishment.
Some people think this relative ostracism was due to his loner character and indifference to politics. I wonder whether Keys
was excluded because proponents of the cholesterol hypothesis were threatened by his lifelong habit of independent thinking.

The medical professor Stephen Phinney remembers a hallway encounter with Keys in the mid-1980s, shortly after the Lipid Research
Clinic Coronary Prevention Trial demonstrated that the drug cholestyramine reduced cholesterol and coronary mortality. Keys
showed Phinney a paper in which he examined HDL and mortality in Minnesota businessmen. In the paper, Keys wrote that HDL
levels predicted heart-related deaths, but not death from all causes. Phinney recalled: "Dr. Keys was fuming, because this
manuscript had been rejected by the major medical journals. Having set the cholesterol-lowering juggernaut in motion, the
nutrition establishment was not about to let him sully the picture by demonstrating that it was not the only factor that determined
important outcomes such as longevity. In his early 80s, Dr. Keys was still way out ahead of the consensus."
¹³

Later, Phinney told me why Keys, a nutritional epidemiologist, was unique in his field. "He understood the complexity of nutritional
metabolism, whereas the pharmacologists either sought to reduce its complexity or ignored it. Pharmacology is a reductionist
discipline— you always want to purify your drug and precisely define its target and its mechanism," said Phinney. "This helps
explain why diet and nutrition struggle for acceptance in the medical mainstream. The Mediterranean diet works better than
atorvastatin"— the statin sold as Lipitor, which lowers LDL—" because it breaks the reductionist rule by harnessing the power
of a combination of nutrients working against both cholesterol and inflammation."
¹⁴

Ancel Keys left a substantial legacy— and a complicated one. He was right to praise antioxidant-rich vegetables, monounsaturated
olive oil, and fish. In 1994, the famous Lyon study found the greatest protection against heart disease in the Mediterranean
diet was provided by omega-3 fats found in fish.

Yet Keys also set the stage for a battle against the alleged dangers of saturated fats in traditional foods such as butter—
dangers that were oversold, if not by Keys himself then certainly by the medical-pharmaceutical complex, which took up the
anticholesterol campaign with enthusiasm befitting a crusade.

The Cholesterol Skeptics

THE OLD ADVICE— butter
high cholesterol
heart attack— was too crude to be accurate. New advice is more subtle; even the conventional wisdom holds that margarine
is "worse than" butter, and we know that high HDL is good. Yet I have some sympathy for the researchers who reduced the message
to an antibutter slogan. They meant well. If you labor in a complex field— and heart disease is certainly that— the appetite
for simple answers can be maddening.

People will ask, If butter doesn't cause heart disease, what does? Well, I venture, genes, lack of exercise, inflammation,
free radicals, smoking, and industrial foods like trans fats, sugar, and corn oil. I believe this is accurate and reasonably
complete; I hope it's also brief enough to keep people from nodding off. I don't envy doctors, who are forced by the clock
and by anxious patients to reduce complex disease etiology, diagnosis, and treatment to three-minute summaries.

On diet and disease, this is as simple as I can make it without doing injustice to accuracy or uncertainty:
traditional foods are good
for you.
There are various ways to go about proving this. You can feed people corn or coconut oil, and see that corn oil lowers HDL
and coconut oil doesn't. You can observe whether people who eat extreme diets (e.g., all meat) get heart disease. And so on.
Such studies convinced me that you can eat whatever you want— except industrial foods. If that satisfies you, close this book
and enjoy butter and eggs. Those who would like to know more about heart disease may wish to read on.

The quintessential disease of civilization, heart disease was rare before 1900, and rare it remains in preindustrial groups.
In the United States, the first heart attack was reported in 1912, and by midcentury heart disease was the nation's biggest
killer. Today cardiovascular diseases— conditions of the heart and blood vessels, including angina, stroke, congestive heart
failure, and heart disease— are still the leading cause of death. All cardiovascular diseases combined kill about a million
Americans a year, men and women in pretty much equal numbers. Heart disease alone is responsible for five hundred thousand
deaths every year.
¹⁵

There is also good news. Since peaking in the late 1960s, the death rate from cardiovascular diseases has fallen. In 1999,
the mortality rate was less than 40 percent of the rate in 1950.
¹⁶
Back then, heart disease was an acute, often fatal condition. After a heart attack, patients were simply sent home to rest
and to die. Today doctors are adept at various treatments— clot-busting drugs, tiny balloons to open arteries, bypass surgery—
so that heart disease, though still prevalent, is more often chronic than fatal. These advances keep many of the sixty-four
million Americans with heart disease alive longer.

In the first stage of heart disease,
angina,
blood flow to the heart is restricted. When blood flow stops, that's a
myocardial
infarction,
or
heart attack.
Together, angina and a heart attack are what doctors call
coronary heart disease. Arteriosclerosis,
or hardening of the arterial walls, is partly a function of age; with time, the smooth, elastic arterial cells become fibrous
and stiff. Arteriosclerosis may be a protective measure to prevent the arteries from expanding under the pressure of blood;
veins, which carry blood to the heart at much lower pressure, don't stiffen in this way. When arterial walls become thick
and swollen, it's called an
atheroma-,
many atheromas are known as
atherosclerosis.
Atheromas, which contain calcium, cholesterol, and fats, may burst, causing blood clots or heart attacks.

The cholesterol hypothesis holds that saturated fats raise cholesterol and cholesterol clogs arteries, but a number of researchers,
some of whom belong to a network called the International Committee of Cholesterol Skeptics, are doubtful. "The truth is that
the cholesterol theory has never been proven," says Dr. Kilmer McCully, whom I quoted earlier on oxidized cholesterol in powdered
eggs. "Elevation of blood cholesterol is a symptom— not a cause— of heart disease." Here is Ravnskov, a leading skeptic and
the author of
The Cholesterol Myths:
"When the cholesterol campaign was introduced in Sweden in 1989,1 was very surprised.

Having followed the scientific literature about cholesterol and cardiovascular disease superficially for years, I could not
recall any study showing that high cholesterol was dangerous to the heart, or that any type of dietary fat was more beneficial
or harmful than another. I became curious and started to read more systematically. Anyone who reads the literature in this
field with an open mind soon discovers that the emperor has no clothes."
¹⁷

At first I thought the skeptics might be few in number, but I found them all over. In 1978, a National Institutes of Health
conference held to discuss the drop in death rates from heart attacks since the 1960s was unable to account for the decline
by changes in fat and cholesterol consumption or blood cholesterol.
¹⁸
Yet this statement got little attention. In 1998, a British National Health Service review found that blood cholesterol alone
was a "relatively poor predictor of individual risk."
¹⁹
The authors concluded that for the general population, "cholesterol screening is unlikely to reduce mortality and can be
misleading or even harmful."

As you might imagine, the cholesterol skeptics have not received a hearty embrace from the medical and pharmaceutical establishment.
In Finland, supporters of the anticholesterol campaign belittled Ravnskov's book on television, and then— literally— set the
book on fire. When I read
The Cholesterol Myths,
I got excited too, but it didn't put me in the mood to burn books. Quite the opposite: it made me want to buy them. I began
to read medical journals and textbooks, and soon I was a skeptic, too.

Does saturated fat raise cholesterol? Not in unhealthy ways. Early studies did show that certain saturated fats, when compared
with polyunsaturated oils, raise total cholesterol, but now we know that total cholesterol is a poor predictor of heart disease.
In fact, saturated fats raise HDL and polyunsaturated oils lower it. The National Cholesterol Education Program is clear about
the virtues of HDL: "the higher, the better." The general effect of saturated fats is to restore a healthy balance of HDL
and LDL. Coconut oil, for example, raises HDL if it's low, and lowers LDL if it's high. As we've seen, certain saturated fats
(stearic acid in beef and chocolate, and palmitic acid in butter and coconut oil) are good for HDL and LDL ratios.
²⁰
There is abundant evidence from traditional diets to absolve saturated fats. In Nigeria, for example, the Fulani get half
their calories from fats, half of which are saturated. Despite what the theory predicts, they have low LDL.
²¹

Does high blood cholesterol predict heart disease? In a striking number of cases, the link is weak. Since 1948, researchers
have studied the residents of Framingham, Massachusetts, a city near Boston. After a few years, directors of the now famous
Framingham Heart Study reported findings that became the bedrock of the cholesterol hypothesis: when they sorted people by
low, normal, and high cholesterol, those with high levels had more fatal heart attacks. But almost half the heart attack patients
had normal or low cholesterol. In Russia, a twelve-year study of more than sixty-four hundred men found those with low cholesterol
had more heart disease.
²²
A study in rural China found that neither cholesterol nor LDL was linked to heart disease.
²³

I could cite many other examples— and the cholesterol skeptics do, at length— but the point, I hope, is clear: in Massachusetts,
Russia, and China, something other than high cholesterol must be to blame for a large number of heart disease cases.

Cholesterol may be a concern for a relatively small group of people: younger men at high risk of heart disease, such as those
who've already had one heart attack. In 1987, the Framingham data showed an association between high cholesterol and mortality
for men under forty-seven. But for men older than forty-seven and for all women, there was
no association
between cholesterol and death rates from all causes, including heart disease.
²⁴
According to James Wright of the University of British Columbia, compared with high blood pressure, obesity, diabetes, and
smoking, cholesterol is the weakest risk factor for women and heart disease.

The Center for Medical Consumers believes that the heart disease-awareness campaign exaggerates risks for women. One hears
that cardiovascular diseases kill almost five hundred thousand women a year in the United States, but nearly 80 percent of
heart-related deaths occur in women older than seventy-five. Associate Director Maryann Napoli described what the Framingham
researchers found: "Cholesterol was identified as one, but only one, of 240 risk factors that included male baldness, creased
ear lobes, and being married to a highly educated woman. Research focused on cholesterol because it is a modifiable risk factor
(translation: drug industry opportunity). Though the Framingham Study found a strong association between . . . cholesterol
and heart disease only in young and middle-aged men, the entire population was . . . instructed to fear this particular risk
factor."