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What
About Dairy?
Looking Behind the Mustache
Dig into nearly anyone's supermarket
shopping cart (with their permission, naturally) and what do you find?
Amid the canned corn, Rice Crispies, carrots and cellophane, you're likely
to unearth a jug of milk, a carton of yoghurt, and a wedge or two of cheese--
even if the basket belongs to one of North America's more-than 12 million
vegetarians.
Thanks to star-spangled
industry promotions and decades of government-sponsored nutrition "education"
in schools, dairy foods are universally revered as a fundamental food
group and the vital building blocks of strong bones and teeth. Understandably,
North Americans generally react with disbelief when informed-- even by
medical authorities-- that dairy foods are not essential for human health,
and that most people on this planet do quite nicely without them.
Even harder to swallow
is the news that a solid and growing body of scientific evidence suggests
that limiting or eliminating dairy products from the diet may be important
to achieving optimal health.
"What do you mean,
'Dairy foods aren't essential?'"
The dairy industry
spends millions of dollars of milk money on high-gloss advertising to
convince us that their products are not only wholesome and chic, but downright
essential for our health. Essential?
"There is no
human requirement for milk from a cow," says Suzanne Havala, RD,
author of the American Dietetic Association's "Position Paper on
Vegetarian Diets" and several books on nutrition. "The use of
milk and its products in our country is strictly a cultural tradition,"
she notes. "There are millions of people around the world who never
consume cow's milk and are none the worse for it."
Dietitians Virginia
and Mark Messina, PhD, echo this view in their 1996 book The Vegetarian
Way. "Vegetarians who avoid dairy products may seem to be choosing
an unusual diet by Western standards, but are actually choosing a typical
diet by world standards...The belief that milk is essential in the diet
is clearly incorrect."
The calcium scoop
But aren't dairy products
our only reliable source of precious calcium?, you might ask. You'd certainly
think so listening to Lauren Bacall, Christie Brinkley and the other mustachioed
celebrities paid handsomely to urge us on to ever greater heights of milk
consumption.
Although milk, cheese,
yoghurt, butter and the like are not pivotal to our welfare, calcium certainly
is. In small amounts in the bloodstream, it plays a critical part in blood
clotting, muscle contraction, heartbeat maintenance, and proper nerve
function. About 99 percent of calcium (roughly three pounds total) is
stored in our bones and teeth, which rely upon the mineral for their strength.
When needed, calcium is released from our bones into the blood.
Calcium is calcium,
however, whether it's from broccoli or cottage cheese. "There's no
best source of calcium," explains Robert Heaney, a professor with
the Osteoporosis Research Center at Creighton University School of Medicine.
"The sheer quantity of calcium in dairy products certainly makes
them attractive sources, but they have no monopoly on calcium. There's
no reason in the world why you couldn't get an adequate intake from a
vegetable source."
In fact, nutritional
anthropologists believe that our earliest ancestors-- who got most of
their calcium from wild plant foods-- had higher calcium intake than their
milk-quaffing contemporaries. Anthropologists also think that until 10,000
years ago or so, all humans were lactose intolerant.
Calcium and bone health:
What's the connection?
The dairy industry
tirelessly advances the notion that their calcium-rich foods are veritable
guarantors of unbreakable bones. Problem is, there is scant support for
this assertion in the medical literature. There is no clear scientific
evidence that high calcium intakes alone-- even the Recommended Dietary
Allowance (RDA) of 800 mgs-- can ensure bone health.
"It might surprise
you to know that throughout the world people who consume the most calcium
actually have the poorest bone health," say the Messinas. "The
idea that dosing yourself with calcium will automatically keep your bones
in good shape is just plain wrong."
Indeed, researchers
have found that nations with the greatest calcium intake have the highest
rates of osteoporosis and hip fracture, and that there are relatively
few fractures among populations where calcium levels are not so high.
After studying bone fracture rates worldwide, researcher JA Kanis concluded
that the differences in fracture rates, "cannot be accounted for
by differences in dietary intake of calcium but may relate more to physical
activity [which promotes strong bones]." Of course the dairy industry
disputes these findings, continuing to insist that every man, woman and
child would benefit from drinking at least three glasses of milk a day.
The recipe for healthy
bones clearly calls for more than simply ingesting copious amounts of
calcium-rich foods. Certainly, calcium intake is keenly important, particularly
during childhood, early adulthood and up to the age of 30-35 when our
bones achieve their peak mass and stop growing. But retaining the calcium
we've stored in our bones appears to be even more vital. This is especially
the case in our late 40s or so, when our bones begin to break down faster
than they can be rebuilt, alas, an inevitable part of aging. Indeed, research
from hundreds of subjects indicates that preventing calcium loss is actually
three to four times more important in determining calcium balance-- that
is, whether we gain, maintain or lose calcium from our bones-- than is
calcium intake. And one of the greatest instigators of calcium loss, it
turns out, is a high-protein diet.
The protein drain
Protein, and especially
protein from animal sources, makes our urine acidic, a condition the body
attempts to remedy by drawing calcium, an alkaline mineral, from the bones.
Eventually, this calcium is lost, flushed from the body in the urine.
What makes this even more alarming is that many North American adults
typically eat twice the recommended amount of protein. (The RDA for protein
is 50 grams for women and 60 for men.) Researchers who reviewed 16 studies
examining the protein-calcium relationship found that when protein intake
is above 75 grams per day, more calcium is lost in the urine than is retained
in the body. Researchers speculate that this level of protein intake alone
could account for the bone loss commonly seen in postmenopausal women!
If you already eat
a plant-based diet, you'll be comforted to know that meat-free diets produce
less acid than those containing meat, and that vegan diets produce less
acid than those including dairy products. According to one recent study,
by eliminating animal protein altogether from the diet, people can cut
urinary calcium losses in half.
All of which leads
Havala and others to conclude that Americans would need less calcium in
their diets if they simply ate less protein. But researcher Heaney calls
this a moot point, believing that Americans aren't willing to shift substantially
away from meaty, high-protein fare. "For most people it is easier
to fix the calcium intake component of the problem than to fix the calcium
excretory loss problem. An extra serving or two of low-fat or skim milk
each day will do the job nicely," Heaney claims.
Pediatrician Charles
Attwood, MD, represents an opposing viewpoint. "It seems that milk,
with its excessive protein, may be part of the calcium problem instead
of a solution."
If, for whatever reason,
you include dairy foods in your diet, Havala suggests using only nonfat
varieties, and limiting your intake of these to one or two servings a
day. Havala also recommends that you avoid 1% or 2% milk and yoghurt because
of their high-fat content.
Okay, so how much calcium
DO I need?
- Fact: The RDA for
calcium is established higher than it otherwise would be in order to
compensate for calcium losses due to American's high consumption of
protein.
- Fact: People worldwide
develop and maintain strong bones on levels of calcium considerably
below the 800-mg RDA. The World Health Organization recommends 400-500
mgs daily.
- Fact: Studies indicate
that the bones of vegetarians are just as dense as those of non-vegetarians,
and that osteoporosis is not more common in vegetarians than in nonvegetarians.
- Fact: Because vegetarians
generally have lower protein intakes and absorb and retain calcium better,
they may have lower calcium needs.
Yet, despite these
facts, most medical authorities still recommend that people eating a plant-based
diet aim to achieve the RDA. Why? Some believe that the evidence that
vegetarians need less dietary calcium is not yet conclusive. Others worry
that vegetarians will get the erroneous idea that calcium isn't important.
For most people, the
RDA can quite easily be fulfilled by eating a varied diet with at least
several servings of calcium-rich foods each day. (See sidebar.) Children,
teens and young women should be especially careful to include these foods
since their calcium needs are relatively high compared to others. Some
people may choose to take supplements as added insurance. Of course one
advantage of meeting calcium needs with plant foods is that many are also
excellent sources of antioxidants, fiber, folic acid, complex carbohydrates,
iron and other important vitamins and minerals you won't find in milk
products.
Meeting calcium needs
without dairy has gotten a lot easier with the availability of a huge
assortment of fortified nondairy "milks" made from soy, rice
and nuts. (Not all are fortified, so check the labels carefully.) An 8-ounce
glass of fortified soy milk has 2-300 mgs of calcium, compared to the
300 mgs in the same glass of cow's milk. (An 8-ounce glass of fortified
orange juice also has about 300 mgs of calcium.) Most health food stores
and some grocery stores also stock cheeses, yoghurts and frozen desserts
made from rice milk, soy milk and fruit juices. Though these products
might not taste exactly like what you're used to, with an open mind and
adventurous spirit you may find their distinctive flavors divine.
Beyond Bones
While the question
of whether dairy foods contribute to or detract from the well- being of
our skeletons often occupies center stage, there are additional serious
health concerns that might make you wary of dairy.
- Allergies: Milk
is the most common cause of food allergy. A recent study found that
one way to reduce the number of allergies in infants is for the breastfeeding
mother to avoid consuming, or make very limited use of cow's milk.
- Anemia: Overreliance
on milk in children can lead to anemia, as milk is very low in iron,
and drinking large quantities of it can crowd iron-rich foods from the
diet. In young infants, protein from cow's milk can cause intestinal
bleeding, another possible cause of anemia.
- Colic: Sensitivity
to cow's milk can cause colic, a digestive ailment in infants. Colic
can cause problems even in infants who aren't drinking cow's milk but
whose mothers are.
- Food safety concerns:
Washington Post columnist Colman McCarthy chides that milk is tainted
with so many that it should be sold by prescription only. Dairy farmers
regularly administer drugs and growth hormones to cows to boost milk
production. Investigations have routinely found residues of these veterinary
pharmaceuticals in milk and other milk products, some of which may raise
cancer risks. One compound approved for use in 1993 and now widely employed
by commercial dairies is the controversial genetically engineered Bovine
Growth Hormone (BGH). Many feel that this compound-- which increases
milk production in an era of serious milk surplus-- poses grave potential
health risks for consumers (including elevated antibiotic residue levels
in milk) while favoring large-scale factory farms at the expense of
small dairy producers. Unfortunately, producers who shun BGH are forbidden
from labeling their products as such. Only organic dairy foods are certified
to be free of antibiotic and BGH residues.
- Heart disease:
Dairy products are major contributors of fat, saturated fat and cholesterol
to the diet. According to cardiologist Dean Ornish, MD, "Milk rates
second only to beef as the largest source of saturated fat in the American
diet." Consider, for example, that one glass of 2% milk has as
much saturated fat as three strips of bacon. Almost half the calories
in whole milk come from fat.
- Insulin-dependent
diabetes: Recent research indicates that consuming cow's milk throughout
adolescence increases the risk of developing Type I diabetes. About
1 million Americans have this disease. (13)
- Lactose intolerance:
Many people cannot stomach lactose, the sugar in milk, because they
lack the necessary digestive enzyme. Some people are also sensitive
to milk protein. An estimated 50 million Americans experience intestinal
discomfort after consuming dairy products. Symptoms include bloating,
stomach pain, cramps, gas or diarrhea.
- Women's health
concerns: Studies indicate that osteoporosis, which afflicts 20 million
American women, and ovarian cancer are most common in those countries
with the highest consumption of dairy food and lowest in those countries
with low dairy intake. According to gynecologist Christiane Northrup,
MD, author of Women's Bodies Women's Wisdom, other health problems
associated with the consumption of dairy foods include benign breast
conditions, recurrent vaginitis, acne, menstrual cramps, fibroids, chronic
intestinal upset and increased pain from endometriosis.
Such findings prompted
breast surgeon Robert Kradjian, MD, in 1993 to review more than 500 medical
articles written about milk since 1988. "How would I summarize the
articles?," Kradian asks. "First of all, none of the
authors spoke of cow's milk as an excellent food, free of side effects.
The main focus of the published reports seem to be on intestinal colic,
intestinal irritation, intestinal bleeding, and anemia, allergic reactions
in infants and children as well as infections such as salmonella... In
adults the problems seemed centered more around heart disease and arthritis,
allergy, sinusitis, and the more serious questions of leukemia, lymphoma
and cancer."
Conclusions
1. Dairy foods are
not essential for human health
2. All the nutrients
dairy foods offer can be obtained from plants foods with the added bonus
of protective nutrients unavailable in milk products
3. Plant foods are
protective against many diseases, dairy foods elevate the risks of numerous
diseases
4. Deciding whether
to include them in your diet boils down to personal preference.
5. Debate over dairy
has grown more acrimonious in the last decade
6. There are enough
studies, experts and opinions to satisfy any number of positions.
7. Only certainty:
the more you know about dairy foods, the harder it is to eat them with
the assurance that they are doing a body good.
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