DHA (docosahexaenoic acid)

DHA (docosahexaenoic acid)

Topics you will find:
DHA as a Brain Food
DHA Supplements: Pregnancy/Lactation
DHA Food Sources
DHA and A.D.D.
DHA for Students
DHA AS A BRAIN FOOD

Fats make up sixty percent of the brain and the nerves that run every system in the body. So, it stands to reason that the better the fat in the diet, the better the brain. So, with all the fat eaten by the average American, why don't we have more geniuses in this country? The average American brain is getting enough fat, but it's not getting the right kind of fat.

Think of your brain as the master gland that sends chemical messengers throughout the body, telling each organ how to work. An important group of these chemical messengers are the prostaglandins (so-called because they were originally discovered in the prostate gland). Prostaglandins initiate the body's self-repair system. The body needs two kinds of fat to manufacture healthy brain cells (the message senders) and prostaglandins (the messengers). These are omega 6 fatty acids (found in many oils, such as safflower, sunflower, corn, and sesame oils) and omega 3 fatty acids (found in flax, pumpkin seeds and walnuts, and coldwater fish, such as salmon and tuna). The foods from which oil can be extracted are generally the foods highest in essential fatty acids.

Most important to brain function are the two essential fatty acids, linoleic (or omega 6) and alpha linolenic (or omega 3). These are the prime structural components of brain cell membranes and are also an important part of the enzymes within cell membranes that allow the membranes to transport valuable nutrients in and out of the cells.

When the cells of the human body - and the human brain - are deprived of the essential fatty acids they need to grow and function, the cells will try to build replacement fatty acids that are similar, but may actually be harmful. Higher blood levels of "replacement fatty acids" are associated with diets that are high in hydrogenated fats and diets that contain excessive amounts of omega 6 fatty acids. Levels of replacement fatty acids have been found to be elevated in persons suffering from depression or Attention Deficit Disorder. A diet rich in omega 3 fatty acids (such as the LNA from flax oil or the EPA and DHA from fish oils) not only provides the body with healthy fats, but it also lowers the blood level of potentially harmful ones, such as cholesterol and, possibly, even reversing the effects of excess trans fatty acids.

Using the lock and key analogy will help you understand how the brain communication system works. Neurotransmitters are biochemical messengers that carry information from one brain cell to another, sort of like sparks flying across the gap between nerve cells. Each cell membrane contains a series of locks. The various message carriers (prostaglandins and neurotransmitters) are like keys. The keys and the locks must match. When the cell membrane is unhealthy because it is made of the wrong kind of replacement fatty acids, the keys won't fit, and brain function suffers. Nutrients may also fail to fit in a mismade lock.

The eye is a perfect example of the importance of getting the right kind of fat. The retina of the eye contains a high concentration of the fatty acid DHA, which the body forms from nutritious fats in the diet. The more nutritious the fat, the better the eye can function. And since most people are visual learners, better eyes mean better brains.

Western diets contain too much of the omega 6 fatty acids and too little of the omega 3's. Omega 3 fatty acids are found in ground flax seeds and flaxseed oil, coldwater fish (primarily salmon and tuna), canola oil, soybeans, walnuts, wheatgerm, pumpkin seeds, and eggs.

Smart fats for growing brains*. Fats can also influence brain development and performance, especially at either end of life -- growing infants and elderly people. In fact, there are two windows of time in which the brain is especially sensitive to nutrition: the first two years of life for a growing baby and the last couple decades of life for a senior citizen. Both growing and aging brains need nutritious fats.

The most rapid brain growth occurs during the first year of life, with the infant's brain tripling in size by the first birthday. During this stage of rapid central nervous system growth, the brain uses sixty percent of the total energy consumed by the infant. Fats are a major component of the brain cell membrane and the myelin sheath around each nerve. So, it makes sense that getting enough fat, and the right kinds of fat, can greatly affect brain development and performance. In fact, during the first year, around fifty percent of an infant's daily calories come from fat. Mother Nature knows how important fat is for babies; fifty percent of the calories in mother's milk is fat.

Different species provide different types of fat in their milk, fine-tuned to the needs of that particular animal. For example, mother cows provide milk that is high in saturated fats and low in brain-building fats, such as DHA. This helps their calves grow rapidly, though it may not do much for their brains. In adult cows, the brain is small compared with the body. Cows don't have to do a lot of thinking to survive. In human infants, the brain grows faster than the body. Highly developed brains are important to human beings, so human milk is low in body- building saturated fats and rich in brain-building fats, such as the fatty acid DHA (docosahexaenoic acid), an omega 3 fatty acid.

DHA is the primary structural component of brain tissue, so it stands to reason that a deficiency of DHA in the diet could translate into a deficiency in brain function. In fact, research is increasingly recognizing the possibility that DHA has a crucial influence on neurotransmitters in the brain, helping brain cells better communicate with each other. Asian cultures have long appreciated the brain-building effects of DHA. In Japan, DHA is considered such an important "health food" that it is used as a nutritional supplement to enrich some foods, and students frequently take DHA pills before examinations.

Just how important is DHA for brain development? Consider these research findings:

* Infants who have low amounts of DHA in their diet have reduced brain development and diminished visual acuity.
* The increased intelligence and academic performance of breastfed compared with formula- fed infants has been attributed in part to the increased DHA content of human milk.
* Cultures whose diet is high in omega 3 fatty acids (such as the Eskimos who eat a lot of fish) have a lower incidence of degenerative diseases of the central nervous system, such as multiple sclerosis.
* Experimental animals whose diets are low in DHA have been found to have smaller brains and delayed central nervous system development.
* Some children with poor school performance because of ADD, have been shown to have insufficient essential fatty acids in their diet. (See A.D.D. - A Nutritional Deficiency?)

DUMB FATS

Just as there are fats that improve how the brain functions, there are fats that hinder the brain's work. The dumbest fats are those that are man-made through the process of hydrogenation. These fats are referred to on package labels as "hydrogenated" or "partially hydrogenated." A diet rich in these fats not only deprives the eater of the smart fats, but they can actually interfere with the action of smart fats on brain function.

NOURISHING TEEN BRAINS

Even though the brain has completed most of its growth by adolescence, it continues to make vital connections. This is another window of opportunity for brain growth when a healthy diet is important. However, adolescence may be a period when there is a lack of essential fatty acids in the diet. There are several reasons for this deficiency: adolescents tend to eat a lot of saturated fat foods and foods that contain hydrogenated fats. Young athletes often restrict their fat intake in order to keep fit and trim. When they cut out fat, in general, they also cut out healthy fats. Teen brains need more fish and fewer fries.

NUTRITIP: Fat Food for Growing Brains

While a baby is in the womb, the brain grows more rapidly than in any other stage of infant or child development. And during the first year after birth, the brain continues to grow rapidly, tripling in size by an infant's first birthday. So, it would make sense for a pregnant and lactating mother to supplement her diet with brain-building nutrients, primarily the omega 3 fatty acids found in fish and flax oil (one tablespoon of flax oil daily, four ounces of tuna or salmon three times a week). In fact, some nutritionists recommend that pregnant and lactating women take 200 milligrams of DHA supplements a day.

The recommended dosage of Neuromins� DHA is 100mg per day. Those who eat little or no DHA rich foods should take 200mg of Neuromins� DHA per day. Today, the average Americans daily intake of DHA is significantly lower then it was 50 years ago. Similarly, the level of DHA in breast milk of American women is significantly lower then it was 50 years ago. An additional 200mg of DHA a day increases the benefits of the average American mother�s breastmilk to near historic levels.

DHA FOOD SOURCES

The best sources of DHA are: seafood, algae, and especially coldwater fish. Omega-3 fatty acids are nature's antifreeze. In general, the colder the water, the higher the omega-3 content in the fish oil. Popular sources of DHA are: salmon, sardines, and tuna. Eggs and organ meats have a small amount of DHA in them, but the healthiest source of dietary DHA is seafood. Two 4-ounce servings of omega-3-rich fish per week should yield a sufficient amount of omega-3 fatty acids, especially DHA. Besides fish oils, vegetable oils (primarily flaxseed, soy, and canola) are also rich sources of omega 3 fatty acids, with flaxseed oil being the best. The two F's, fish and flax, are the top brain-building foods for growing children, and adults.