Saturated fat

Health issues

Diets high in saturated fat correlate in some studies with an increased incidence of atherosclerosis and coronary heart disease . Some studies suggest that replacing saturated fats in the diet with unsaturated fats will increase one's ratio of HDL to LDL serum cholesterol.

This argument is based on the "Lipid Hypothesis", as described below in the 5th paragraph of the Controversy section.

Controversy

It has been alleged that the many studies of saturated fat in the diet do not distinguish between saturated fat and trans fat. With this bias, such studies do not isolate saturated fat as unhealthful, so saturated fat could be healthful. Foods such as peanuts and pure peanut butter (not having added hydrogenated vegetable oils) contain saturated fat but no trans fat. Several studies have shown that a diet including regular consumption of peanuts or peanut butter can significantly lower LDL cholesterol while raising HDL levels compared to an average American diet, in turn reducing the risk of cardiovascular disease by as much as 21%. Critics of saturated fat can counter that the health benefits of these foods might stem not from their saturated fat content, but rather their high levels of mono- and polyunsaturated fat.

Studies suggesting replacing saturated fats with unsaturated fats to increase the ratio of HDL to LDL serum cholesterol, have to be analysed within the concept of processed/damaged/oxidised/Trans-shaped versus naturally found/undamaged saturated fats, since saturated fat is extremely stable and easily withstands cooking/roasting heats, they resist oxidation and can be stored the longest.

Other foods that contain healthy saturated fat if not hydrogenated or oxidized are peanuts and peanut butter. It should be noted that the fat found in all foods is a mixture of saturated, monounsaturated (olive oil), and polyunsaturated (canola oil, corn oil, soybean oil). It's the preponderance of one type of fat that classifies that food.

Saturated fats have been reported to have nutritional benefits, according to Dr. Mary Enig, a biochemist and nutritionist on fats. Lauric acid, a medium chain fatty acid, "has antimicrobial properties and is the precursor to monolaurin, the antimicrobial lipid (Enig, Mary G. Know Your Fats. p.114)." She also notes that lauric acid "gives human milk its major antimicrobial properties, and it may be a conditionally essential fatty acid since it cannot be made by mammals other than the lactating female and must be obtained from the diet (p.194)."

There is a growing concern among nutritionists that saturated fats have been demonized in the past century. Much of it is based on the Lipid Hypothesis, which argues that saturated fats cause heart disease. There is also another issue of concern about the history behind saturated fat and trans fat. Hydrogenated oils were actually portrayed as much healthier than the naturally occurring saturated fats. The Oiling of America shows that big business was the culprit in demonizing saturated fats.

Another confounding issue may be the formation of exogenous (outside the body) advanced glycation endproducts (AGEs) and oxidation products generated during cooking, which it appears some of the studies have not controlled for. It has been suggested that, "given the prominence of this type of food in the human diet, the deleterious effects of high-fat foods may be in part due to the high content in glycotoxins, above and beyond those due to oxidized fatty acid derivatives." The glycotoxins, as he called them, are more commonly called AGEs.

Molecular description