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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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