Shoes, Ships, and Sealing Wax

fat...brain...stuff

I'm not typing much at all...trying to limit unnecessary computer time...because my right thumb is numb. And my right arm is tingling. And I know what that's a sign of and I don't like it...

But I am so intrigued by this story about omega-3 fatty acids and the brain from today's Post that I want to mark it for later.

Here's the part that has me really fascinated:

Essential fatty acids are fats that can't be produced by the body but are required for good health. They play key roles in the structure of brain cells and of the eye, particularly the retina. They're vital for each neuron's membrane, both its outer protection and its means of accessing key nutrients. And it is these essential fats that regulate the growth of long tendrils called axons that enable neurons to communicate with each other.
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Omega-3s and omega-6s are close enough in chemical structure to be able to compete for the same molecular machinery that allows entry into the brain. (Omega-3 fatty acid molecules have three carbon atoms on one end; omega-6 fatty acids have six.)

That fact might simply still be a little quirk of nature had not a huge shift occurred in diets during the past century. In 1909, Americans got most of their fat from free-range animals, which have higher levels of omega-3s than the chicken, beef and pork commonly eaten today. They also consumed about 0.02 pounds per year of soybean oil -- a number that increased gradually until about 1960, when "soybean oil took over the U.S. food chain," says William Lands, a retired biochemist with NIAAA. "It was like a tsunami."

By 1999, soybean oil -- a major ingredient in crackers, bread, salad dressings, baked goods and processed food of all sorts -- accounted for 20 percent of total calories consumed in the United States, according to the U.S. Department of Agriculture. Per capita consumption reached 25 pounds per year. "That means that there has been an 1,000-fold increase in [consumption of] omega-6 fatty acids" over 100 years, Hibbeln says. "So we have literally changed the composition of people's bodies and their brains. A very interesting question, which we don't know the answer to yet, is to what degree the dietary change has changed overall behavior in our society."