Milk: No Longer Recommended or Required
A substantial body of
scientific evidence raises concerns about health risks from cow�s
milk products. These problems relate to the proteins, sugar, fat,
and contaminants in dairy products, and the inadequacy of whole
cow�s milk for infant nutrition.
Health risks from milk
consumption are greatest for infants less than one year of age, in
whom whole cow�s milk can contribute to deficiencies in several
nutrients, including iron, essential fatty acids, and vitamin E.
The American Academy of Pediatrics1 recommends that
infants under one year of age not receive whole cow�s milk.
Cow�s milk products are very
low in iron,2 containing only about one-tenth of a
milligram (mg) per eight-ounce serving. To get the U.S.
Recommended Daily Allowance of 15 mg of iron, an infant would have
to drink more than 31 quarts of milk per day. Milk can also cause
blood loss from the intestinal tract, which, over time, reduces
the body�s iron stores. Researchers speculate that the blood loss
may be a reaction to proteins present in milk.3
Pasteurization does not eliminate the problem. Researchers from
the University of Iowa recently wrote in the Journal of
Pediatrics that �in a large proportion of infants, the feeding
of cow milk causes a substantial increase of hemoglobin loss. Some
infants are exquisitely sensitive to cow milk and can lose large
quantities of blood.�3
Although concerns are
greatest for children in the first year of life, there are also
health concerns related to milk use among older children and some
problems associated with cow�s milk formulas.
Milk Proteins and Diabetes
Several reports link
insulin-dependent diabetes to a specific protein in dairy
products. This form of diabetes usually begins in childhood. It is
a leading cause of blindness and contributes to heart disease,
kidney damage, and amputations due to poor circulation.
Studies of various countries
show a strong correlation between the use of dairy products and
the incidence of diabetes.4 A recent report in the
New England Journal of Medicine5 adds substantial
support to the long-standing theory that cow�s milk proteins
stimulate the production of the antibodies6 which, in
turn, destroy the insulin-producing pancreatic cells.7
In the new report, researchers from Canada and Finland found high
levels of antibodies to a specific portion of a cow�s milk
protein, called bovine serum albumin, in 100 percent of the 142
diabetic children they studied at the time the disease was
diagnosed. Non-diabetic children may have such antibodies, but
only at much lower levels. Evidence suggests that the combination
of a genetic predisposition and cow�s milk exposure is the major
cause of the childhood form of diabetes, although there is no way
of determining which children are genetically predisposed.
Antibodies can apparently form in response to even small
quantities of milk products, including infant formulas.
Pancreatic cell destruction
occurs gradually, especially after infections, which cause the
cellular proteins to be exposed to the damage of antibodies.
Diabetes becomes evident when 80 to 90 percent of the
insulin-producing beta cells are destroyed.
Milk proteins are also among
the most common causes of food allergies. Often, the cause of the
symptoms is not recognized for substantial periods of time.
Milk Sugar and Health Problems
Many people, particularly
those of Asian and African ancestry, are unable to digest the milk
sugar, lactose. The result is diarrhea and gas. For those who can
digest lactose, its breakdown products are two simple sugars:
glucose and galactose. Galactose has been implicated in ovarian
cancer8 and cataracts.9,10 Nursing children
have active enzymes that break down galactose. As we age, many of
us lose much of this capacity.
Fat Content
Whole milk, cheese, cream,
butter, ice cream, sour cream, and all other dairy products aside
from skim and non-fat products contain significant amounts of
saturated fat, as well as cholesterol, contributing to
cardiovascular diseases and certain forms of cancer. The early
changes of heart disease have been documented in American
teenagers. While children do need a certain amount of fat in their
diets, there is no nutritional requirement for cow�s milk fat. On
the contrary, cow�s milk is high in saturated fats, but low in the
essential fatty acid linoleic acid.
Contaminants
Milk contains frequent
contaminants, from pesticides to drugs. About one-third of milk
products have been shown to be contaminated with antibiotic
traces. The vitamin D content of milk has been poorly regulated.
Recent testing of 42 milk samples found only 12 percent within the
expected range of vitamin D content. Testing of ten samples of
infant formula revealed seven with more than twice the vitamin D
content reported on the label, one of which had more than four
times the label amount.11 Vitamin D is toxic in
overdose.12
Osteoporosis
Dairy products offer a false
sense of security to those concerned about osteoporosis. In
countries where dairy products are not generally consumed, there
is actually less osteoporosis than in the United States. Studies
have shown little effect of dairy products on osteoporosis.13
The Harvard Nurses� Health followed 78,000 women for a 12-year
period and found that milk did not protect against bone fractures.
Indeed, those who drank three glasses of milk per day had more
fractures than those who rarely drank milk.14
There are many good sources
of calcium. Kale, broccoli, and other green leafy vegetables
contain calcium that is readily absorbed by the body. A recent
report in the American Journal of Clinical Nutrition
found that calcium absorbability was actually higher for kale than
for milk, and concluded that �greens such as kale can be
considered to be at least as good as milk in terms of their
calcium absorbability.�15 Beans are also rich in
calcium. Fortified orange juice supplies large amounts of calcium
in a palatable form.16
Calcium is only one of many
factors that affect the bone. Other factors include hormones,
phosphorus, boron, exercise, smoking, alcohol, and drugs.17-20
Protein is also important in calcium balance. Diets that are rich
in protein, particularly animal proteins, encourage calcium loss.21-23
Recommendations
There is no nutritional
requirement for dairy products, and there are serious problems
that can result from the proteins, sugar, fat, and contaminants in
milk products. Therefore, the following recommendations are
offered:
- Breast-feeding is the
preferred method of infant feeding. As recommended by the
American Academy of Pediatrics, whole cow's milk should not be
given to infants under one year of age.
- Parents should be alerted
to the potential risks to their children from cow's milk use.
- Cow's milk should not be
required or recommended in government guidelines.
- Government programs, such
as school lunch programs and the WIC program, should be
consistent with these recommendations.
References
1. American Academy of Pediatrics, Committee on Nutrition. The use
of whole cow?s milk in infancy. Pediatrics 1992;89:1105-9.
2. Pennington JAT, Church HN. Food values of portions commonly
used. New York, Harper and Row, 1989.
3. Ziegler EE, Fomon SJ, Nelson SE, et al. Cow milk feeding in
infancy: further observations on blood loss from the
gastrointestinal tract. J Pediatr 1990;116:11-8.
4. Scott FW. Cow milk and insulin-dependent diabetes mellitus: is
there a relationship? Am J CLin Nutr 1990;51:489-91.
5. Karjalainen J, Martin JM, Knip M, et al. A bovine albumin
peptide as a possible trigger of insulin-dependent diabetes
mellitus. N Engl J Med 1992;327:302-7.
6. Roberton DM, Paganelli R, Dinwiddie R, Levinsky RJ. Milk
antigen absorption in the preterm and term neonate. Arch Dis Child
1982;57:369-72.
7. Bruining GJ, Molenaar J, Tuk CW, Lindeman J, Bruining HA,
Marner B. Clinical time-course and characteristics of islet cell
cytoplasmatic antibodies in childhood diabetes. Diabetologia
1984;26:24-29.
8. Cramer DW, Willett WC, Bell DA, et al. Galactose consumption
and metabolism in relation to the risk of ovarian cancer. Lancet
1989;2:66-71.
9. Simoons FJ. A geographic approach to senile cataracts: possible
links with milk consumption, lactase activity, and galactose
metabolism. Digestive Diseases and Sciences 1982;27:257-64.
10. Couet C, Jan P, Debry G. Lactose and cataract in humans: a
review. J Am Coll Nutr 1991;10:79-86.
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fortified milk and infant formula. New Engl J Med
1992;326:1178-81.
12. Jacobus CH, Holick MF, Shao Q, et al. Hypervitaminosis D
associated with drinking milk. New Engl J Med 1992;326:1173-7.
13. Riggs BL, Wahner HW, Melton J, Richelson LS, Judd HL, O?Fallon
M. Dietary calcium intake and rates on bone loss in women. J Clin
Invest 1987;80:979-82.
14. Feskanich D, Willett WC, Stampfer MJ, Colditz GA. Milk,
dietary calcium, and bone fractures in women: a 12-year
prospective study. Am J Publ Health 1997;87:992-7.
15. Heaney RP, Weaver CM. Calcium absorption from kale. Am J Clin
Nutr 1990;51:656-7.
16. Nicar MJ, Pak CYC. Calcium bioavailability from calcium
carbonate and calcium citrate. J Clin Endocrinol Metab
1985;61:391-3.
17. Dawson-Hughes B. Calcium supplementation and bone loss: a
review of controlled clinical trials. Am J Clin Nutr
1991;54:274S-80S.
18. Mazess RB, Barden HS. Bone density in premenopausal women:
effects of age, dietary intake, physical activity, smoking, and
birth control pills. Am J Clin Nutr 1991;53:132-42.
19. Nelson ME, Fisher EC, Dilmanian FA, Dallal GE, Evans WJ. A 1-y
walking program and increased dietary calcium in postmenopausal
women: efect on bone. Am J Clin Nutr 1991;53:1304-11.
20. Nielsen FH, Hunt CD, Mullen LM, Hunt JR. Effect of dietary
boron on mineral, estrogen, and testosterone metabolism in
postmenopausal women. FASEB J 1987;1:394-7.
21. Zemel MB. Role of the sulfur-containing amino acids in
protein-induced hypercalciuria in men. J Nutr 1981;111:545.
22. Hegsted M. Urinary calcium and calcium balance in young men as
affected by level of protein and phosphorus intake. J Nutr
1981;111:553.
23. Marsh AG, Sanchez TV, Mickelsen O, Keiser J, Mayor G. Cortical
bone density of adult lacto-ovo-vegetarian and omnivorous women. J
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