A Brief History of the Science

If the so-called evidence-based advice that we are being given is obviously wrong, how did it become the dominant dietary ethos? Dietitians and their associations are fond of pointing out that their professionals are university trained in evidence-based science for 4 full years. If this is the case, how can they be wrong about everything?

They're not wrong about everything, just about a lot of fundamental things. And it is because the science they cite is based on older science that is so well-established that it is no longer questioned. There exists an almost religious conviction that the facts are established. Thus it never needs to be reexamined, the curricula need not be overhauled.

"Big pharma"  likes it this way too. It has invested billions into research into very lucrative drugs that it promotes constantly. It advertises heavily, spending millions each year, flying medical professionals to their conferences. There, doctors and their assistants are wined, dined and influenced to prescribe the latest drug, given promotional materials, charts and generally made to feel obligated to support their benefactor(s).

The Accepted Science

The basic science that is accepted by dietitians is the so-called "Lipid Hypothesis." The lipid hypothesis was largely conjured up by a physiologist named Ancel Keys.

In his famous "Seven Country Study", Keys purported to show that nations which consumed the lowest amounts of fats (lipids) also had the lowest rates of cardiovascular disease. The seven selected countries Keys included in his report all lined up with his hypothesis that increased fat consumption correlated to increased CVD (cardiovascular disease). This eventually, despite a great deal of initial opposition, became the accepted view on the relationship between fat and heart disease upon which much of our food pyramid is based.

Eat less fat and save your heart.

An Inconvenient Truth
(apologies to President Gore)

Unfortunately for the world, and fortunately for Keys, this led to vast changes in what foods were promoted as "healthy". Fats, particularly animal fats, were to be avoided at all costs. Butter was replaced with cheap-to-produce margarine. Lard and Tallow were replaced with seed oils such as rapeseed, canola, safflower and peanut oils. Meat was to be reduced to 2 serves per week.

What then was left for consumers to consume?

Industry to the rescue. Low-fat foods were devised, all the fat was chemically or mechanically removed from foods and sweet, safe, satisfying sugar was added. Skim milk, margarine, low-fat foods proliferated. As did obesity, metabolic syndrome (syndrome X), type 2 diabetes, heart disease, cancer, and Alzheimer's disease.

Somehow, it wasn't clear that the change to low-fat foods and seed oils were the cause of this decline in health. Rather, it was seen as a decline despite the overwhelming evidence that the dietary advice was correct. Another culprit was sought and found.

People were just plain lazy. People were becoming fat and sick because they lacked the self-control to eat less, and the will to exercise enough: their energy expenditure was less than their energy consumed. The food pyramid and advice were fine and dandy, but people were becoming more sedentary. That was the problem.

How Did We Get Here?

So, we know that there must have been a mistake made somewhere, but where?

Ancel Keys published his Seven Country Study. This was proof that fat consumption correlated with heart disease. The seven countries that Keys chose to represent his data were not the only countries in his study - they were the seven of 22 countries that fit his prior hypothesis. Keys cherry-picked his data.