Can Three B Vitamins a Day Keep a Heart Attack Away?
As we saw in last week’s article, homocysteine is a risk factor for
heart disease. One of the most appealing features of the homocysteine
theory is its simplicity and ease of application to the prevention of
heart disease. The first step in lowering homocysteine is to get a
simple blood test to measure it.
Such tests, which are becoming widely available, typically cost
between $45 and $120 and are covered by many insurers. If the
homocysteine level is higher than seven micromoles per liter of plasma,
it is too high according to most researchers now studying the matter.
Homocysteine levels are controlled by three B vitamins – B6, folic
acid, and B12. By avoiding toxins that deplete the body of these B
vitamins and by eating a diet that is rich in them, an individual can
lower homocysteine levels and therefore the risk of heart attack and
stroke. The most common toxins that deplete the body of B vitamins and
raise the level of homocysteine are alcohol, tobacco, and coffee.
Alcohol, Tobacco and Coffee
There are three known interrelated effects of heavy alcohol
consumption: elevated homocysteine levels; greater risk of stroke; and
interference with metabolism of folic acid, vitamin B6, and vitamin B12.
Since homocysteine is implicated in vascular disease, elevated
homocysteine levels could explain the greater incidence of stroke among
heavy drinkers, and the depletion of the B vitamins could explain the
elevated homocysteine.
Tobacco smokers also have high homocysteine levels that increase
markedly with daily number of cigarettes smokes. And they too have
lower levels of B6, folic acid, and B12. Coffee consumption has long
been suspected of being a contributing factor in the development of
coronary heart disease. A 1997 study showed a marked increase in
homocysteine concentration with increased intake of coffee.
The combination of cigarette smoking and high coffee intake was
associated with particularly high homocysteine concentration, which
could explain why this combination has been shown to have a
particularly strong effect on heart attack risk.
Processed Food
Eliminating toxins that prevent the absorption of vitamins B6,
B12, and folic acid is the first step in lowering homocysteine levels.
The next step is eating a diet that provides optimal intake of these
vitamins. This means eliminating processed foods from the diet and
maximizing intake of fresh, whole, raw foods.
Vitamins B6, B12, and folic acid are each exquisitely sensitive to
destruction by harsh physical or chemical treatments involved in food
processing, refining, and preservation. They are destroyed by milling,
heating, chemical additives, radiation, and storage.
For example, in milling wheat into white flour, 50 to 90 percent of
vitamin B6 is destroyed. Losses of vitamin B6 amount to 40 to 50
percent in canning meats and fish and 60 to 70 percent in canning
vegetables.
Losses of folic acid range from 25 to 75 percent when fresh raw
foods are compared with refined, processed, and preserved foods.
Canning as a method of preserving foods was invented in the early
19th century to feed Napoleon’s armies. In the canning process, food
is cooked and heated to a high temperature. Two of the vitamins that
are most sensitive to this form of food preservation are B6 and folic
acid.
Surprisingly enough, freezing also involves heating at high
temperatures. To prevent deterioration of frozen foods, particularly
vegetables and fruits, the food is first blanched. This process
involves rapid heating of food in boiling water for a short period of
time.
The heat inactivates the food’s enzymes that otherwise would cause
slow deterioration of the food while frozen.
This step also destroys 10 to 15 percent of the vitamins that are
sensitive to heat. Two of the most sensitive to destruction by heat are B6 and folic acid. The radiation of foods with X-rays or gamma
rays has been advocated to increase the shelf-life of foods. Three of
the most sensitive vitamins to the effects of this type of radiation
are vitamin B6, folic acid, and vitamin B12.
Sources of Vitamin B6, Folic Acid, and B12
The way to maximize the intake of vitamin B6, folic acid, and B12
is to maximize the intake of whole, fresh, unprocessed foods. Folic
acid is found in significant amounts in fresh green vegetables like
asparagus, broccoli, spinach, cabbage , romaine lettuce, red leaf
lettuce, turnip greens, collard greens, and any other green leafy
vegetable.
It is found in legumes like lentils, navy beans, garbanzo beans,
black beans, and white beans. It is found in fruits such as oranges,
pineapple, raspberries. It is found in grains, particularly wheat germ.
Vitamin B6 is also widely distributed in food. It is found in
animal protein like beef, chicken, lamb, pork, fish, and eggs. It is
found in whole grains like whole wheat, unpolished rice, and wheat germ
where it is primarily concentrated.
It is found in vegetables: asparagus, broccoli, Brussels sprouts,
cabbage, cauliflower, corn, potatoes, and spinach. It is in fruits, in
particular avocado (the fat in avocado is menstruated20and is good for
you) and bananas. It is in nuts and seeds and legumes. B12 is found
only in animal foods: meats, poultry, fish, eggs, and dairy.
The Problem of Getting These B Vitamins
The problem is not the availability of these foods in the American
diet. The problem is the destruction of the vitamins they contain
through processing and methods of food preparation. That is why it is
so important to eat whole, unprocessed, fresh foods and to eat them raw
or as lightly cooked as is consistent with palatability.
There is another problem with obtaining adequate amounts of
vitamins B6, B12, and folic acid. And that is not intake but
absorption. As we have seen alcohol and tobacco interfere with the
absorption of all three of these vitamins.
But other factors do as well. Chief among these is aging. As
people age their ability to absorb vitamin B12 declines, and B12
deficiency is common among the elderly. A B12 deficiency makes folic
acid unavailable in the body. To counteract malabsorption, vitamin
supplementation may be required.
And it may also be necessary when diet alone fails to bring down
homocysteine levels, for whatever reason. No clinical consensus on how
to treat homocysteine with vitamin supplementation has yet emerged.
Presumably that will be established when clinical trials now under way
are completed.
Lowering Protein
Homocysteine is not found in food. It is a by-product of protein
metabolism. It is formed form methionine (ma-THI-a-neen) which is an
essential amino acid found in all protein, but particularly animal
protein. Could there be another way of lowering homocysteine levels by
consuming less of the methionine it is made from? Kilmer McCully, “Father of the Homocysteine Theory,” thinks so. He considers arteriosclerosis a disease of “protein intoxication,” and while Americans are busy focusing on fat avoidance to lower cholesterol, he believes they should be reducing their consumption of animal protein to lower homocysteine.
However, he does not advocate a vegetarian diet, but rather a
balanced diet. An excess of methionine will cause a build up of
homocysteine – only if it is not balanced by the proper B vitamins. He
recommends that 20 to 25 percent of calories be protein in the form of
meat, fish, poultry, eggs, milk, cheese, and beans.
About 25 to 35 percent should be fat. And 40 to 55 percent should
be carbohydrates from fresh vegetables, fruits, and whole grains.
Refined carbohydrates from sugar and white flour are excluded.
By eliminating toxins like alcohol, tobacco, and coffee that
deplete the body of B vitamins; by eliminating processed foods that are
depleted or devoid of B vitamins; by eating fresh, whole, raw foods
that are rich in B vitamins; by balancing intake of animal protein with
sufficient B vitamins; and by supplementing with B vitamins, if
necessary, homocysteine can be lowered and with it the risk of
cardiovascular disease.
Mary Lou Williams, M. Ed., is a lecturer and writer in the field of
nutrition. She welcomes inquiries. She can be reached at (239)
267-6480.