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3. "There are no government endorsed alternatives to dairy products
because no other food has a similar nutrient profile. Therefore
it would be inappropriate to present milk alternatives beside the
milk group."
Calcium is the key nutrient provided by milk and milk products,
and their calcium content has given dairy foods the status of an
exclusive food group.1 Other nutrients provided by milk can be obtained
elsewhere. While milk is an excellent source of calcium, this does
not mean that it is the only reliable source. There are many Canadians
that do not consume the recommended numbers of servings of dairy
foods each day, and for these people as well as for vegetarians,
it would be of tremendous value to know what other foods could provide
this valuable nutrient.
1. Health and Welfare Canada. Action Towards Healthy Eating. Report
of the Task Group and Technical Group on Canada's Food Guide and
the Task Group on Food consumption to the Communications/Implementation
Committee. Minister of Supply and Services Canada, 1990.
Page 17
1. "A replacement food would have to be the nutritional equivalent
of dairy products. None exists. There is no one unsupplemented food
that could realistically serve as a milk alternative. According
to Becoming Vegetarian, the criterion for an alternative to milk
products is that it be "calcium-rich". Health Canada attributes
not one but 16 significant nutrients to milk. "
While it is true that Health Canada attributes 16 significant nutrients
to milk, it is calcium that is the key nutrient considered when
foods are included or excluded from this group by Health Canada.1
It is interesting to note that our critics are quick to say that
the basis for the meat alternatives group is protein, not the minerals
iron and zinc. However, iron and zinc are listed as nutrients that
these foods provide. With reference to the milk and milk products
-- calcium is the basis for this group, not the many other nutrients
it provides.
1. Health and Welfare Canada. Action Towards Healthy Eating. Report
of the Task Group and Technical Group on Canada's Food Guide and
the Task Group on Food consumption to the Communications/Implementation
Committee. Minister of Supply and Services Canada, 1990.
2. "Zinc absorption may be inhibited by fibre as well as phytate
and oxalates. Although Canada's Food Guide to Healthy Eating includes
beans, tofu and peanut butter under the meat and alternatives group
, they are not good sources of zinc."
Why would it be acceptable to include foods that are not nutritionally
equal to meat, poultry and fish in this group if they are good sources
of the key nutrient protein, but unacceptable to include foods that
are not identical nutritionally to dairy even if they are good sources
of their key nutrient, calcium? Seems like a double standard to
us. For the record, beans and tofu are good sources of zinc (15-25%
of the RNI).
Page 18
1. "Despite the authors' implications to the contrary, neither
the government nor the dairy industry has ever claimed that milk
alone could prevent or cure osteoporosis."
Our exact statement was: "People get the impression that the best
way to prevent , or even cure, osteoporosis is to drink milk." We
were illustrating the one extreme of how people perceive dairy products
in our culture. We never stated that the dairy industry or the government
ever claimed that milk alone could cure or prevent osteoporosis.
We object to having our words twisted to mean something very different
than what we actually said.
If we look at Dairy Bureau advertising, we can see why people get
this impression. (Canadian Living: September, 1995).
"Eye Opening Data: The Osteoporosis Society of Canada
New figures show that a staggering 1 in 3 women after age fifty
develops this disabling bone disease. In fact, osteoporosis is more
common in older women than heart attacks, diabetes and strokes.
To stay healthy, a woman must be well-nourished. This means eating
enough nutritious foods, including the recommended 2-4 servings
of milk products, every day."
2. "It's probably stating the obvious to point out that although
Africans and Orientals may not drink milk, Canadians don't exactly
consume huge amounts of insects or bok choy, good sources of calcium
for those two groups respectively."
This comment borders on racism. The consumption of insects is considered
uncivilized by North Americans standards. Inferring that African
people eat huge amounts of insects to meet calcium needs is an insult
to many of these people and demonstrates a lack of awareness of
their food patterns. In reality, insects are a part of the diet
for only a limited number of African people.
Oriental Canadians do continue to use Chinese greens such as bok
choy as important sources of calcium. One need only look as far
as local Oriental markets.
3. "...the implication that osteoporosis is nonexistent in other
cultures is misleading."
Once again, our critics are inferring that we made statements that
we did not make. Stating that "...we need to look at the eating
patterns of cultures in Africa or the Orient that don't include
milk in their diets, and yet have bone health as good or better
than ours." is hardly saying that osteoporosis is nonexistent in
these cultures.
4. "A Hong Kong study has shown that children who meet their calcium
needs with diary products have stronger, denser bones than other
children..."
Our critics cite studies in China and Hong Kong demonstrating how
bone health improves if milk is consumed. Considering the high incidence
of lactose intolerance, the over-population and environmental impact
of massive increase in dairy consumption in the Orient, would it
not make more sense culturally, economically and environmentally
to fortify soymilk with calcium?
Page 20
1. "...here are just a few examples of why the incidence of osteoporosis
may be somewhat higher in western countries."
The nutritionists at the Dairy Bureau agree that some non-dairy
consuming cultures have lower rates of osteoporosis than ours. They
go on to list the possible reasons for this phenomenon. It seems
rather ironic that the first reason they cite is that "almost half
of Canadian women consume less than the recommended two to four
servings of milk and milk products per day". This hardly provides
a logical explanation of why some non-dairying cultures have less
osteoporosis than Western countries. Perhaps the time has come that
we acknowledge the fact that people can achieve adequate bone health
without the use of dairy foods.
2. "In a chapter on life without dairy products, why discuss the
role played by meat in the prevalence of osteoporosis? In our section
on calcium (p. 25) we establish that calcium loss due to the protein
content of dairy products is minimal because of their high calcium:protein
ratio. Moreover, phosphorus, which is found in dairy products, encourages
calcium retention and significantly offsets the effect of protein
intake."
This is the Dairy Bureau nutritionists response to the following
statement: "While calcium losses are counteracted, at least in part,
by the high phosphorus levels in foods such as meats, increasingly
our high protein intake is being targeted as a significant factor
contributing to our high incidence of osteoporosis."
In a chapter about meeting calcium needs on a plant-based diet,
it is very important to discuss calcium balance and the factors
that both negatively and positively affect this balance. High protein,
meat-centered Western diets can increase calcium requirements due
to the oxidation of excess sulfur-containing amino acids which generate
endogenous acid, the excretion of which results in acidic urine
and increased calcium losses.1 While we are criticized for bringing
up the effect of meat on calcium balance, our critics go on to defend
the protein and phosphorus content of milk. By doing so they imply
that we have condemned milk as a source of calcium due to its protein
content. Once again, the Dairy Bureau nutritionists have made it
appear as though we have said something which we did not say. We
would never state or even imply that milk has a detrimental effect
on calcium balance because we do not believe that it does.
1. Health and Welfare Canada. Nutrition Recommendations: The report
of the Scientific Review Committee. Ministry of Supply and Services
Canada. 1990; p. 133.
3. "It has been found that a mixed diet, one that includes high
intakes of both protein and phosphorus, greatly diminishes the effect
of protein on urinary calcium and calcium balance."
The Dairy Bureau nutritionists cite a commentary titled "Protein
intake and the calcium economy" by Dr. Robert Heaney as their source
for this statement. After carefully reading this article, we were
unsure of how our critics arrived at the conclusion that high intakes
of phosphorus greatly diminish the effect of protein on calcium
balance. Here is what Dr. Heaney says about calcium and phosphorus
in this commentary:
"Phosphorus is well known to decrease urinary calcium loss. Precisely
for this reason, phosphorus supplements are part of the management
of patients with recurrent renal stones; also, for the same reason,
it is commonly believed that the hypocalciuric effect of the coingested
phosphorus offsets the hypercalciuric effect of the protein. Indeed,
the phosphorus in these food protein sources does lower urinary
calcium. However, that does not mean that coingested phosphorus
offsets the negative effect of protein on calcium balance. What
is less well recognized is that, in addition to its effect on the
kidney, phosphorus increases the calcium content of the digestive
secretions and, hence, increases endogenous calcium loss through
the gut. In more than 500 individual studies, using a parenteral
calcium tracer (unpublished observations), my colleagues and I have
found that endogenous fecal calcium increases with phosphorus intake.
Furthermore, this increase is of about the same magnitude as the
concurrent decrease in urinary calcium."1
We would interpret Dr. Heaney's words to mean that the phosphorus
present in high protein foods does not offset the negative effects
of the protein to the extent that many people believe it does. To
verify our interpretation of this work, we contacted Dr. Heaney
personally on October 16, 1996. Our question to Dr. Heaney was to
what extent does phosphorus affect calcium balance. His answer was
really very simple -- phosphorus doesn't factor in, particularly
over the long term where humans are concerned. He noted however,
that calcium losses caused by protein can be offset by consuming
more calcium.
1. Heaney, R. Protein intake and the calcium economy. J.Am.Diet.Assoc.
1993: Vol.93;No.11:1259-1260.
Page 21
1. Our critics cite a quote from Nutrition Recommendations for
Canadians regarding the impact of calcium on bone health. The essence
of this quote is that protein is only a concern if phosphorus intake
does not increase in conjunction with protein intake. This quote
taken from page 78 of the protein section, not pages 132-133 of
the calcium section as our critics claimed. It is interesting to
note that the conclusion of the scientific review committee experts
for the calcium section on pages 132-133, is somewhat different:
"It cannot be assumed, however that the low calcium intake of women
living in countries with a cereal-based food economy (400-500 mg/day)
is necessarily adequate for women consuming a Western diet. The
oxidation of excess sulfur amino acids in the high-protein Western
diet generates endogenous acid, the excretion of which results in
an acidic urine. The efficiency of the parathyroid hormone-dependent
renal reabsorption of calcium from the filtered urine decreases
with increasing acidity. Unless this tendency toward an increased
urinary loss of calcium is counteracted by other factors, it can
result in a negative calcium balance (i.e. bone loss)."
"Urinary calcium is also affected by the intake of phosphorus.
Excess dietary phosphate produces a mild depression in serum calcium
similar to that produced by a low calcium intake. The consequent
rise in serum parathyroid hormone induces an analogous increase
in mobilization of calcium from the skeleton, and renal reabsorption
of calcium from the urine. However, there does not appear to be
a compensating increase in the efficiency of calcium reabsorption
such as occurs following a decrease in dietary calcium. "
The controversy surrounding the effects of phosphorus on calcium
retention has been raging for several years. Since 1990 (publish
date of Nutrition Recommendations) our understanding of these issues
has improved and we have more evidence which would indicate that
increasing phosphorus is not necessarily an advantage1, and indeed,
when the calcium:phosphorus ratio is low, the excess phosphorus
could be a disadvantage to bone health. 2-4
1. Heaney, R. Protein intake and the calcium economy. J.Am.Diet.Assoc.
1993: Vol.93;No.11:1259-1260.
2. Draper, H., scythes, C. Calcium, phosphorus and osteoporosis.
Fed.Proc. 40:2434-2438, 1981.
3. Calvo, M. and Park, Y. Changing phosphorus content of the U.S.
diet: potential for adverse effects on bone. Amer.Inst.Nutr. 1168(s)-1180(s),
1996.
4, Anderson, J. Calcium, phosphorus and human bone development.
Amer.Inst.Nutr. 1153(s)-1158(s), 1996.
2. "This statement only supports the consumption of dairy products;
why then is it included in a chapter on life without dairy products?"
[referring to our statements regarding the research on the bone
health of vegans and lacto-ovo vegetarians].
Once again, the Dairy Bureau nutritionists assume that we are against
the use of dairy foods and lacto-ovo vegetarians. This is simply
not the case. We believe dairy products are an excellent source
of calcium, and readily agree that their use makes it easier for
people to meet calcium needs. We also believe that people choose
not to consume dairy products can meet their nutritional needs when
their diet is appropriately planned. In this particular section
of the chapter we are discussing the calcium intakes of North Americans
and the research that has been done on their bone health. We would
have no reason to exclude research on the bone health of lacto-ovo
vegetarians, as this information is of great value.
Page 22-23
1. "Both the Osteoporosis Society of Canada and the National Institutes
of Health support increased calcium intakes, throughout the life
cycle" ["referring to:"...for people in good health, there appears
to be no advantage in higher-than-recommended intakes {of calcium}]."
Our critics once again have taken our words out of context. The
quote they are refuting is taken from a paragraph called "Calcium
Supplements". In this section we explain the role of calcium supplements,
and when their use is warranted. The above statement is made as
a word of caution so people will not be overzealous in their use
of supplements. Calcium supplements can interfere with zinc absorption,
and thus, we would not recommend taking higher than recommended
amounts for healthy people. We would consider the recommendations
of the Osteoporosis Society of Canada and the National Institute
of Health as valid recommendations, and our caution refers to amounts
higher than professionally recognized recommended intakes for healthy
people.
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