Please don’t tell the British Medical Journal that I republished their article on saturated fat and heart disease but this opinion piece is a fairly nice example of 40 years of dogma around a specific health topic that has been based on absolutely nothing and led us in completely the wrong direction for the last 4 decades. The consumption of saturated fats is only now being questioned by the conventional medical system, but you would have thought that based on the pitiful results of drugs that focus on lowering fats like cholesterol, we would have caught a clue a little earlier.
I have been a proponent of saturated fats in the diet for a long time and just recently have almost completed adopted an extremely high fat diet, consisting mostly of nuts, coconut oil and butter, along with veggies and organic natural sources of meat and eggs. For the last few months I have been more loosely following this strategy, with a plan to go to a full out ketogenic diet on January 1st, 2014. I plan to continue to follow my blood chemistry to make sure this diet is right for me, however this adaptation of the paleo diet seems to work very well for my attention, energy and metabolism.
Saturated fat is not the major issue – Lets bust the myth of its role in heart disease
Aseem Malhotra, Interventional cardiology specialist registrar, Croydon University Hospital, London
BMJ, 2013; 347 doi: http://dx.doi.org/10.1136/bmj.f6340 (Published 22 October 2013)
Scientists universally accept that trans fats—found in many fast foods, bakery products, and margarines—increase the risk of cardiovascular disease through inflammatory processes.
But“saturated fat” is another story. The mantra that saturated fat must be removed to reduce the risk of cardiovascular disease has dominated dietary advice and guidelines for almost four decades.Yet scientific evidence shows that this advice has, paradoxically, increased our cardiovascular risks. Furthermore, the government’s obsession with levels of total cholesterol, which has led to the over medication of millions of people with statins, has diverted our attention from the more egregious risk factor of atherogenic dyslipidaemia. Saturated fat has been demonized ever since Ancel Keys’s landmark “seven countries” study in 1970.
This concluded that a correlation existed between the incidence of coronary heart disease and total cholesterol concentrations, which then correlated with the proportion of energy provided by saturated fat. But correlation is not causation. Nevertheless, we were advised to cut fat intake to 30% of total energy and saturated fat to 10%.”
The aspect of dietary saturated fat that is believed to have the greatest influence on cardiovascular risk is elevated concentrations of low density lipoprotein (LDL) cholesterol. Yet the reduction in LDL cholesterol from reducing saturated fat intake seems to be specific to large, buoyant (type A) LDL particles, when in fact it is the small, dense (type B) particles (responsive to carbohydrate intake) that are implicated in cardiovascular disease.
Indeed, recent prospective cohort studies have not supported any significant association between saturated fat intake and cardiovascular risk.
Instead, saturated fat has been found to be protective. The source of the saturated fat may be important. Dairy foods are exemplary providers of vitamins A and D. As well as a link between vitamin D deficiency and a significantly increased risk of cardiovascular mortality, calcium and phosphorus found commonly in dairy foods may have antihypertensive effects that may contribute to inverse associations with cardiovascular risk.
One study showed that higher concentrations of plasma trans-palmitoleic acid, a fatty acid mainly found in dairy foods, was associated with higher concentrations of high density lipoprotein, lower concentrations of triglycerides and C reactive protein, reduced insulin resistance, and a lower incidence of diabetes in adults.
Red meat is another major source of saturated fat. Consumption of processed meats, but not red meat, has been associated with coronary heart disease and diabetes mellitus, which may be explained by nitrates and sodium as preservatives.
The notoriety of fat is based on its higher energy content per gram in comparison with protein and carbohydrate. However, work by the biochemist Richard Feinman and nuclear physicist Eugene Fine on thermodynamics and the metabolic advantage of different diet compositions showed that the body did not metabolise different macronutrients in the same way.
Kekwick and Pawan carried out one of the earliest obesity experiments,published in the Lancet in 1956.
They compared groups consuming diets of 90% fat, 90% protein, and 90% carbohydrate and showed that the greatest weight loss was in the fat consuming group. The authors concluded that the “composition of the diet appeared to outweigh in importance the intake of calories.” The “calorie is not a calorie” theory has been further substantiated by a recent JAMA study showing that a “low fat”diet resulted in the greatest decrease in energy expenditure, an unhealthy lipid pattern, and increased insulin resistance in comparison with a low carbohydrate and low glycaemic index diet.
In the past 30 years in the United States the proportion of energy from consumed fat has fallen from 40% to 30% (although absolute fat consumption has remained the same),yet obesity has rocketed.