Sunday, August 1, 2010

Brain Function, Nutrition and a clear mind.

Your brain runs on blood sugar, using an incredible 20% of the carbohydrates you take in. It prefers to take it's blood sugar in a certain way, however. Simply put, it likes a steady supply, and dislikes wild fluctuations. Simple carbohydrates - processed flour products and sugary foods - cause wild fluctuations. These cause a rush of sugar into the bloodstream, which triggers a balancing rush of insulin, leading to a plunging blood sugar level (hypoglycemia ). This can cause the release of adrenal hormones (called a "sugar high") that squeezes stored sugar from the liver, sending blood sugar levels back up.

Now you're on a blood sugar roller-coaster, with "sugar highs"and "sugar blues." The ups and downs of blood sugar and adrenal hormones can also stimulate neurotransmitter imbalance, causing you to feel fidgety, irritable, inattentive, and even sleepy. This is not the most conducive state for efficient brain function. Since simple carbohydrates have been implicated in diabetes as well, you may want to consider cutting back on these.

Good Foods For The Brain
The best brain foods are complex carbohydrates. The molecules in these are long, so it takes longer for the intestines to break them down into the simple sugars the body can use. Because of this, they provide a source of steady energy rather than a surge followed by a plunge.
The rate at which sugar from a food enters brain cells and other cells is measured by the "glycemic index" (GI). Foods with a high glycemic index stimulate the pancreas to secrete a lot of insulin , which starts the roller coaster. Foods with a low glycemic index don't push the pancreas to secrete much insulin, so blood sugar levels are steadier.
Fruits: grapefruit, apples, cherries, oranges, and grapes have a low glycemic index. Whole fruit ranks lower than juices, because fiber in the fruit slows the absorption of fruit sugar.
Cereals and grains: oatmeal and bran are best. Spaghetti and rice have a relatively low GI. Corn flakes sugar-coated cereals, and white bread have higher GIs.
Vegetables and legumes: Legumes, including soybeans, kidney beans, chick peas, and lentils are great brain foods. They have the lowest glycemic index of any food. Potatoes and carrots have a much higher GI.
Dairy products: Milk products have low glycemic indexes; higher than legumes, but lower than fruits.
How you prepare and eat your food also affects the way the body and brain uses it. Eating sugary food after a meal of legumes, for example, may slow the absorption of the sugar and prevent the "sugar blues." Fats can also slow sugar absorption, so ice cream will have a lower glycemic index than low fat yogurt with sugary fruit. Over-cooking some starches can be similar to pre-digesting them, thus causing them to feed their sugars into the blood too quickly.
Proteins affect brain performance because they provide amino acids, from which neurotransmitters are made. Neurotransmitters carry signals from one brain cell to another. The better you feed these messengers, the more efficiently they deliver the goods. The amino acids tryptophan and tyrosine, are precursors of neurotransmitters, the substances from which neurotransmitters are made. Tryptophan is an essential amino acid and it must be obtained from the diet. Tyrosine is not an essential amino acid because the body can make it if need be.
Some high protein, low carbohydrate, high tyrosine foods that are likely to rev up the brain are seafood, meat, eggs, soy, and dairy. High carbohydrate, low protein, high tryptophan foods that are likely to calm the brain include: pastries and desserts, bean burritos, chocolate, nuts and seeds (e.g., almonds, filberts, sunflower and sesame seeds), and legumes.

From here it just gets complicated.
People respond differently to differing ratios of protein to carbohydrates in meals, and there are also subtle sensitivities (not quite allergies) to foods that vary from person to person. Experimentation is called for, and since it is your body, you have to do it yourself.
A Final Note About Brain Foods
In studies, children scored higher on tests when on a regimen of daily vitamin supplements. "Experts" will tell you that if you eat a balanced diet, you don't need supplements, which, given the culture here, is really just a sales pitch for vitamins here, isn't it? Who eats a perfectly balanced diet?
A final, final note. Putting the right food in helps, but it's important to get it out too. That's why I nominate fiber as the unsung brain food hero. I don't know how many times I've heard or read about somebody's mind clearing up once their system was cleaned out.

No comments: