Trying the low-fat strategy only made obesity worse
The logical leap from Anitschkow's findings is that eating foods with lots of cholesterol will increase the amount of cholesterol in your body. Doctors ran with this conclusion, announcing a link between dietary fats, blood cholesterol, and heart disease in the 1960s, says Dr. Roger Clemens, who was a member of the USDA 2010 Dietary Guidelines Advisory Committee. In 1984, the National Institutes of Health advised Americans to cut their dietary fat to 30% of total daily calories, kicking off the low-fat craze and convincing a legion of Spandex-clad aerobics practitioners to bring calculators to the grocery store.
The result was a rush to make everything low fat, which usually meant artificial substitutes or a bunch of sugar. Low-fat substitutes for eggs, pasta, and desserts became de rigueur, and, later, the faux-fat nightmare known as olestra was unleashed on unsuspecting consumers. Remember olestra? Maybe it’s better if you don’t.
Did avoiding cholesterol let everyone’s hearts beat as one unified, plaque-free instrument of health and happiness? Not even close. “Obesity rates increased at that time, because instead of eating good-quality fats from the earth, we ate fats made by humans, such as fake butter or foods that were processed to take the fat out,” says dietitian Julie Fortenberry. “Those are things that caused inflammation.” Remember inflammation -- it'll be important.
How could the medical community be so wrong?
Quite a few reasons, actually. First, the studies that concluded dietary cholesterol was the cause of elevated blood cholesterol levels were flawed in their design, since they often couldn't separate cholesterol from things like processed sugar and flour. Also, clinical trials among small populations don’t always translate to the total population, Clemens says, and although words like “association” and “related” (e.g., high cholesterol levels are related to heart disease) sound convincing, the actual evidence “may be quite weak.”
Meta-analyses -- when researchers analyze hundreds of studies conducted over years, and on which most current cholesterol evidence relies -- are more reliable, but they can take decades to develop, according to Clemens. Throw in some aggressive marketing by drug companies and intense lobbying by the food industry, and you have our current misinterpretation of the link between dietary and blood cholesterol.