More olive love.

A fatty acid found in abundance in olive oil and other "healthy" unsaturated fats has yet another benefit: it helps keep the body satisfied to prolong the time between meals.

A new study in the October Cell Metabolism, a publication of Cell Press, reveals that once this type of fat, known as oleic acid, reaches the intestine, it is converted into a lipid hormone (oleoylethanolamide, or OEA) that wards off the next round of hunger pangs. The researchers said it may be the first description of an ingredient in food that directly provides the raw materials for a hormone's production. . .

Previous studies had shown that feeding stimulates cells in the intestinal lining to produce OEA, which, when administered as a drug, decreases meal frequency by engaging receptors called peroxisome proliferator-activated receptors a (PPARa).

Piomelli's team now reports that infusion of fat into the small intestine stimulates the release of OEA, whereas infusion of protein or carbohydrate does not. They also demonstrate that OEA production uses dietary oleic acid and is disrupted in mutant mice lacking the membrane fatty-acid transporter CD36. Treatments that disrupt CD36 or PPARa undermine the hunger control otherwise driven by fat.

Overall, the results suggest that activation of small-intestinal OEA release, enabled by CD36-mediated uptake of oleic acid from the diet, serves as a molecular sensor linking fat consumption to satiety. (Piomelli said satiety is perhaps best described as the opposite of hunger.)

That's useful. A diet with good amounts of oleic acid is satisfying, and that can mean that less is eaten, and done so less often. You may be wondering what foods besides olives contain oleic acid and "other "healthy" unsaturated fats"?

Monounsaturated fatty acids (MUFA) contain one, cis double bond. Oleic acid (C18:1 c9), a MUFA, is the predominant fatty acid in ruminant animal products and comprises from 30-50% of the total fatty acids present. Consumption of diets rich in monounsaturated fatty acids increases good (HDL) and lowers bad (LDL) cholesterol levels (Mensink and Katan, 1989). Canola and olive oils contain predominately MUFA at levels of 58% and 72% of total fatty acids, respectively.

I'm not sure about the claim that "it may be the first description of an ingredient in food that directly provides the raw materials for a hormone's production." The earlier post Fat City cited research that showed -

The fat hormone strongly stimulates insulin's effects on muscle and suppresses fat accumulation in the liver, they report. "This lipid is almost as good as insulin at pushing sugar out of the blood and it prevents fat in the liver," Hotamisligil said. "Delivering fat protects against fat, at least in the liver."

That fat hormone's production was a bit more convoluted but I find is interesting that the old ideas about fat are changing. From that same research PR -

"Most people think that fat is bad and the more you have the worse it is," said Gökhan Hotamisligil of Harvard School of Public Health. "To a certain extent that may be true, but it's far too simplistic. Rather than being one chemical entity, fats are actually a huge soup of things with hundreds of molecules and many different structures. In the blood, high fatty acids and triglycerides are often considered bad and low levels good, but it's not quite that way. It depends what constitutes this soup rather than how much you have."

Check out that article linked above about beef fat. It has some detailed analyses of fats produced using various feeding regimes. I've begun sending my beef to the lab for analysis just to confirm that I am actually producing what the researchers say should result from the methods I use. I'm now pursuing some of the finer points. For example, the fat profile of grass finished meats is far superior to that of grain finished meats, but it also varies a little depending on the kind of grass they get fed.