Our brain consists mostly of fat. Intelligence, heartbeat, muscular movements, all depend on the fat cushioned inside our head. Interestingly, for electrical messages sent to through living tissue, we have nerve cells and their connectors out of fat. All these fats are only polyunsaturated fats.
But humans are unable to make key polyunsaturated fats, or to be more exact, fatty acids. These fatty acids must come from plant sources. The two key unsaturated fatty acids are linoleic and linolenic. Nutritionists call them essential because they are as essential to the diet as vitamins and minerals. Thus, you must get these dietary essentials either from plant foods or from animals that eat plants. Linolenic acid, by the way, is also classed as an omega-3 fatty acid.
The essential fatty acids not only conduct nerve impulses, they form the membrane envelopes of brain, heart, muscles, and all other organs. But the fatty acids structures are inherently unstable. The membrane fatty acids constantly
fall apart and must be replaced with new essential fatty acids eaten in our daily food.
Soybean oil contains a relatively high proportion of linolenic acid(about seven percent). But refining destroys or removes the linolenic acid. Thus when we see soybean oil mentioned on a product label, the product will not likely supply linolenic acid.
Linolenic and linoleic acids belong to two broader series of essential fatty acids, omega-3 and omega-6. Each series consists of several members. Plants make one member each of the two series: linolenic acid(omega-3) and linoleic acid(omega-6). Once eaten, linoleic and linolenic acids are converted by our body biochemistry into other members, respectively, of the two series.
For optimum health, we need both the omega-6 and omega-3 fats in the diet as human body is unable to convert one series to the other.
The absolute amount of omega-3 fats in the diet, however, may be less important. More critical, we need to balance the amount of omega-3 with the amount of omega-6 fats. The ratio of omega 3:omega-6 fats in our diet should be somewhat 1:20. Nutritionists don’t know the best ratio for optimum health, except that 1:20 ratio seems unbalanced.
To boost omega-3 fatty acids in our diet we may intake fresh fish. Plant sources are the best bet. Of the common cooking oils, canola and soybean, contain the highest percentage. There is a catch. As already mentioned, commercial processing destroys linolenic acid.
So what can we do to increase the amount of omega-3(linolenic) acid in our daily diet?
The following foods are especially rich in the omega-3s.
Algae, including spirulina
Beans
Flax seed, freshly ground
Flax seed oil
Fish oil
Whole grains, such as brown rice and whole grain breads
Tofu
Walnuts
Leafy vegetables
Olive oil