Here's a brief explanation of the mechanism
behind the effect of food on serotonin levels
After consumption of a carbohydrate-rich
meal, the hormone insulin is secreted, which causes a lowering of the
blood levels of most amino acids (the building blocks of protein), with
the exception of tryptophan, which is a precursor to serotonin. When
there are high blood levels of tryptophan in relation to other amino
acids, it enters the brain at a higher rate, thus synthesizing more
serotonin. To make matters more interesting, tryptophan is present in
many protein-rich foods, which have been found to prevent serotonin
production. So, you can see how intricate and complex this system is.
In terms of specific translation of foods
into the effects of serotonin, here are some nutritionist suggestions
If you're having trouble falling asleep,
try a small snack of carbohydrate-rich food. Warm milk may work for the
psychological comfort, but also because milk contains a moderate amount
of carbohydrate in the form of lactose (milk sugar).
If you tend to have only carbohydrate
(i.e., plain bagel) before class, and you often fall asleep during
class, try adding some protein by putting some hard cheese (cheddar,
American, Swiss, etc.) or peanut butter on the bagel. Or, have a yogurt
or cottage cheese instead.
For those who are active (athletes or
exercisers), don't be fooled by carbohydrate's relaxing effects. You'll
do best with a diet rich in grains/starches, legumes (dried beans and
peas), fruit, and vegetables in order to get carbohydrates for muscle
energy. Don't skimp on protein either, which is necessary for muscle
growth and repair. Additionally, include some fat to help satisfy the
appetite and promote healthy skin.
Attention span difficulties may or may not
be attributed to what you consume. Many college students go for long
periods of time without eating. This certainly can affect your
concentration. Our brains need glucose, and if we deny it through lack
of food, our bodies have to work harder to break down stored
carbohydrates for glucose that'll be used to feed our brain and central
nervous system. That's why it's a good idea to have something to eat
about every four hours or so. Be prepared by carrying some snacks with
you, especially if you're busy and short on time. Some portable snack
ideas include fruit, low-fat granola bars, nuts, and low-fat crackers.
Different food components have different
effects on the manufacture serotonin.
Sugar (sweets):
Trigger a quick release of insulin that
lowers blood levels of most large amino acids except tryptophan, which
remains in the blood and can enter the brain. As a result, serotonin
levels rise, but blood-sugar levels also rise and fall dramatically.
Refined starch (white bread, white
rice):
Triggers release of insulin that lowers
blood levels of most large amino acids except tryptophan, which remains
in the blood and can enter the brain. As a result, serotonin levels
rise, but blood-sugar levels also rise and fall, sometimes too low.
Whole grain starch (whole wheat,
brown rice, oatmeal):
Triggers a slow, sustained release of
insulin that lowers blood levels of most large amino acids except
tryptophan, which remains in the blood and can enter the brain. As a
result, serotonin levels rise gradually, and blood-sugar levels remain
stable, without the rise and fall experienced with sugar or refined
grains.
Vitamin B6:
Aids in the manufacture of serotonin. A
deficiency of this B vitamin reduces serotonin production and affects
mood and cravings.
Estrogen:
Might inhibit vitamin B6 status and
decrease brain serotonin levels by its affects on neuropeptide Y (NPY).
Tryptophan:
Raises blood levels, then brain levels of
tryptophan, which increases serotonin production.
Protein:
Raises blood levels of all large amino
acids. As a result, only small amounts of tryptophan enter the brain,
serotonin levels do not rise, and cravings for carbohydrates might
increase. A person might also feel more energetic and more clearheaded
as a result of lowered serotonin levels.
Fat:
Omega-3 fatty acids in fish oil raise
serotonin levels, although how they do this is unclear.
Carbohydrates
A desire for sweets seems hardwired into
the brain. A carbohydrate-rich meal or snack stimulates the release of
the hormone insulin from the pancreas, which lowers blood levels of all
amino acids except tryptophan. Normally, tryptophan must compete with
other amino acids for entry into the brain, but insulin eliminates the
competition, allowing tryptophan levels to rise in the brain.
Tryptophan is then converted into serotonin, the neurotransmitter that
regulates sleep, reduces pain and appetite, and generally calms you
down and improves your mood.
What is Melatonin?
Melatonin is manufactured from serotonin.
Therefore, as melatonin levels increase, serotonin levels usually
decrease. Very small amounts of melatonin are found in foods such as
meats, grains, fruits, and vegetables.
Melatonin promotes sleep (makes you
feel sleepy), it
affects reproductive functions and thyroid and adrenal cortex
functions. Insufficient melatonin can result in lack of sleep and
therefore fatigue. Performance may subsequently suffer.
It has also been found that melatonin
levels drop by up to 75% suddenly just before puberty, suggesting the
involvement of melatonin in the regulation of the onset of puberty.
Exposure to light lowers melatonin levels
and increases serotonin levels, hence serotonin levels are lower and
melatonin levels are higher in the winter as compared to the spring and
summer, especially in people with SAD (seasonal affective disorder).
SAD or seasonal affective disorder
(syndrome) is a disorder in which too much melatonin is produced,
especially during the long nights of winter (unless a person is
regularly exposed to an artificial light source), causing profound
depression, oversleeping, weight gain, tiredness, and sadness.
Treatment consists of exposure to bright lights for several hours each
day to inhibit melatonin production.
The pineal gland (where melatonin is
produced) is about the size of a pea and located near the centre of the
brain in humans, is stimulated by nerves from the eyes. The pineal
gland secretes melatonin at night when it’s dark, thus secretes more in
winter when the nights are longer.
This subject can get incredibly deep.
Suffice to say, take diet seriously. There is an amazing amount of
chemistry going on in your body all the time which can adversely affect
your mood and feeling of wellbeing. There will be days when you just
don't feel up to par, but you can't explain why. Hopefully this article
will encourage you research this subject further and take the value of
good diet more seriously.
