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Food For
Thought
DHA AS BRAIN FOOD
William Sears, MD

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.
SMART FATS
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
the problem is it's not 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.
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. An informative book on best fats for growing
brains is: SMART FATS by Dr. Michael Schmidt.
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 from fat.
DHA for Students
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.
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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.
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Smart fats. Besides being found in human milk, DHA appears in
high levels in coldwater fish: sardines, salmon, and albacore tuna.
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.
Dumb fats. Avoid factory fats, which are biochemically-altered
fats recognized by the words "hydrogenated" or "partially
hydrogenated" in the fine print on the package label. The
hydrogenation process produces trans fatty acids which may affect
brain function and health in two ways. The trans fats enter the
cells of the central nervous system where they may compete with the
action of natural fats, so that the nerves in the brain don't
function as well as they were designed to. Also, hydrogenation turns
unsaturated fats into saturated fats, in which the fat molecules
pack together tightly, like lard. Brain researchers worry that the
same type of packing could occur in blood vessels, compromising the
blood flow to the brain. Avoiding hydrogenated fats is especially
important for the growing brains of children, since children who
fill up on these undesirable fats are likely to eat less of the
omega-3 fatty acids that are good for the brain. (For more about the
effects of hydrogenated fats on health and well-being, see
Hydrogenated Fats)
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NUTRITIP:
Feeding Senior Brains
Once upon a time it was believed that the brain doesn't grow as
people get older. New research, however, has shown that the brain
cells continue to branch out and make connections throughout a
person's life. Eating the right diet can help the brain make the
right connections - at all ages.
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PURE MOMS
Over my thirty years in pediatric practice, I have noticed a
striking connection between how children are fed and how healthy
they are. Mothers who consistently don't allow any unhealthy food to
pollute the minds and bodies of their children seem to have
healthier children. I have noticed that these children are sick less
often, and when they do come for periodic checkups they seem more
settled and better behaved. These "pure children" seem to get tagged
with fewer labels, such as "ADD" or "learning disabilities." Even
when these children do warrant such tags, they seem to cope better
with behavioral and learning differences, and they seem less severe.
These moms have made a believer out of me. I truly believe that
there is a connection between how kids are fed and how they act and
learn.
© Copyright 2006 http://www.AskDrSears.com
Used by permission

Martha and William Sears
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