Magnesium:
A Key to Calcium Absorption
By Nan Kathryn Fuchs, Ph.D.
Dr. Fuchs is a nutritional consultant in private practice in
Santa Monica, CA, and is author of "The Nutrition
Detective."
One of the most popular minerals in the news today is calcium,
needed for strong bones and teeth. We are told to take increased
amounts in our diet as a supplement to prevent osteoporosis and
eliminate muscle cramping during menstruation or from
over-exercising. Yet, calcium alone is often not enough. Without
magnesium, calcium may be not fully utilized, and underabsorption
problems may occur leading to arthritis, osteoporosis, menstrual
cramps, and some premenstrual symptoms.
Perhaps the single most significant reason calcium
malabsorption is so common today is due to a discrepancy between
what we eat and how we digest and absorb the nutrients in our
food. Our diets today are very different from those of our
ancestors though our bodies remain similar.
Thousands of years ago, our ancestors ate foods high in
magnesium and low in calcium. Because calcium supplies were
scarce and the need for this vital mineral was great, it was
effectively stored by the body. Magnesium, on the other hand, was
abundant and readily available, in the form of nuts, seeds,
grains, and vegetables, and did not need to be stored
internally.
Our bodies still retain calcium and not magnesium although we
tend to eat much more dairy than our ancestors. In addition, our
sugar and alcohol consumption is higher than theirs, and both
sugar and alcohol increase magnesium excretion through the urine.
Our grains, originally high in magnesium, have been refined,
which means that the nutrient is lost in the refining process.
The quality of our soil has deteriorated as well, due to the use
of fertilizers that contain large amounts of potassium a
magnesium antagonist. This results in foods lower in magnesium
than ever before.
ARTHRITIS AND OSTEOPOROSIS
Two major health problems, arthritis and osteoporosis, may be
caused in part by a magnesium deficiency. When you look at how
calcium is absorbed these problems become easier to understand,
and often can be controlled through diet.
Magnesium is needed for calcium absorption. Without enough
magnesium, calcium can collect in the soft tissues and cause one
type of arthritis. Not only does calcium collect in the soft
tissues of arthritics, it is poorly, if at all, absorbed into
their blood and bones. But taking more calcium is not the answer;
it only amplifies the problem. In fact, excessive calcium intake
and insufficient magnesium can contribute to both of these
diseases. Magnesium taken in proper dosages can solve the problem
of calcium deficiency.
When calcium is elevated in the blood it stimulates the
secretion of a hormone called calcitonin and suppresses the
secretion of the parathyroid hormone (PTH). These hormones
regulate the levels of calcium in our bones and soft tissues and
are, therefore, directly related to both osteoporosis and
arthritis. PTH draws calcium out of the bones and deposits it in
the soft tissues, while calcitonin increases calcium in our bones
and keeps it from being absorbed in our soft tissues. Sufficient
amounts of magnesium determine this delicate and important
balance.
Because magnesium suppresses PTH and stimulates calcitonin it
helps put calcium into our bones, preventing osteoporosis, and
helps remove it from our soft tissues eliminating some forms of
arthritis. A magnesium deficiency will prevent this chemical
action from taking place in our bodies, and no amount of calcium
can correct it. While magnesium helps our body absorb and retain
calcium, too much calcium prevents magnesium from being absorbed.
So taking large amounts of calcium without adequate magnesium may
either create malabsorption or a magnesium deficiency. Whichever
occurs, only magnesium can break the cycle.
In experiments reported in "International Clinical Nutrition
Review," a number of volunteers on a low-magnesium diet were
given both calcium and vitamin D supplements. AU the subjects
were magnesium-depleted and although they had been given adequate
supplements, all but one became deficient in calcium. When they
were given calcium intravenously, the level of calcium in their
blood rose, but only for the duration of the intravenous feeding.
As soon as the intravenous calcium was stopped, the levels
calcium in the blood dropped. However, when magnesium was given,
their magnesium levels rose and stabilized rapidly, and calcium
levels also rose within a few days - although no additional
calcium had been taken.
Dr. Guy Abraham, M.D., a research gynecologist and
endocrinologist in premenstrual syndrome and osteoporosis has
found strong evidence to suggest that women with osteoporosis
have a deficiency of a chemical that is made when they take twice
as much magnesium as calcium. In fact, he has found that when
calcium intake is decreased, it is utilized better than when it
is high. Dr. Abraham is one of many doctors and biochemists who
advocate taking more magnesium to correct calcium-deficiency
diseases.
A magnesium-rich diet can be helpful both for arthritis and to
help prevent osteoporosis. This consists of nuts, whole grains
such as brown rice, millet, buckwheat (kasha), whole wheat,
triticate, and rye, and legumes including lentils, split peas,
and a varieties of beans. A whole grain cereal or bread in the
morning, a cup of bean soup at lunch, a snack of a few nuts, and
serving of brown rice, millet, or buckwheat with dinner should
help increase magnesium when a deficiency is suspected.
At the same time, refined sugar and alcohol should be reduced,
and eliminated when possible to prevent magnesium from being
excreted in large quantities in the urine. You may also want to
re-evaluate the amount of dairy in your diet. If it has been
disproportionately high, reduce or temporarily eliminate it until
some of your symptoms are alleviated, or until you feel more of a
balance has been achieved through the inclusion of whole grains
and legumes. Oriental and Indian diets contain little or no
dairy, yet arthritis and osteoporosis are not major health
problems in these cultures. Their foods consist primarily of
green vegetables, grains, tofu, and seafood, and are twice as
high in magnesium as our average diets.
Calcium causes muscles to contract, while magnesium helps them
relax. When calcium is taken for menstrual cramps it knocks
magnesium out of the cells and makes it more available for
immediate use. However, it depletes the body of magnesium and
ensures that the problem will recur the following month unless
sufficient magnesium is added to the diet. Taking calcium gives
temporary relief of menstrual cramps.
A diet high in dairy and low in whole grains can lead to
excess calcium in the tissues and a magnesium deficiency. The
source of menstrual cramps may be coming from eating too much
cheese, yogurt, ice cream or milk, combined with insufficient
whole grains and beans. Or it could come from taking too much
calcium without enough magnesium. Modifying your diet and
increasing your magnesium supplementation may allow your
menstrual cramps to disappear.
Premenstrual chocolate craving is a phenomenon that has
puzzled a great many women who are not controlled by this
overwhelming urge at other times of the month. Yet chocolate,
which is highest in magnesium of all foods, is often a sign of
magnesium deficiency. If your diet is high in calcium you may
have poor calcium absorption as well. The answer is not to eat
more chocolate, but to increase your magnesium by eating more
whole grains, nuts, seafood, and green vegetables, and by
increasing your magnesium supplements. Your chocolate cravings
will vanish when you have enough magnesium in your diet.
According to Dr. Mildred Seelig, executive president of the
American College of Nutrition, we need an average of 200 mg. more
than we get from the average diet.
Foods highest in magnesium are nuts (especially almonds and
cashews), whole grains, seafood, and legumes (including tofu).
Eat more of these, while reducing sugar and alcohol, which
increase magnesium excretion. Don't overlook one vitamin or
mineral for another since all work together to supply you with
the nutrients you need. And consult your nutritionally- oriented
physician about all nutrients before trying them.
A balanced diet of fresh, whole foods is your best maintenance
diet. But if you have been taking large amounts of calcium and
ignoring magnesium you may want to reverse the proportions until
you achieve a better balance. Sufficient magnesium may be your
missing link.
This page was first uploaded to The Magnesium Web Site on
November 22, 2002
http://www.mgwater.com/
Healthy Water
Association--USA