servings of dairy reported a 27% lower incidence of
kidney stones than those who did not. However,
higher levels of supplemental calcium in older men
and women may be associated with an increased risk
of kidney stones.
High calcium intakes may also increaseprostate
cancer risk. A 2001 Harvard School of Public Health
study showed that men consuming the most dairy
products had about 32% higher risk of developing
prostate cancer than those consuming the least.
The recommendation is not to avoid calcium, but
keep to the recommended guidelines of 1000mg for
adults and not to exceed the upper limit set at 2000–
2500mg of calcium per day.
Health concerns with too much Vitamin D are
rare. Excess vitamin D is generally the result of taking
high dose of supplements rather than from too much
sunlight or food sources alone. The tolerable upper
intake level (UL) for vitamin D at 1,000 IU (25 mcg)
for infants up to 12 months of age and 2,000 IU (50
mcg) IU for children, adults, pregnant, and lactating
women.
Research and general acceptance
Adequate calcium and Vitamin D are key to
reducing the risk of osteoporosis and this is the general
acceptance all mainstream medical associations, mem-
ber societies of the IOF, and part of the recommended
dietary guidelines for many countries.
In 2007, The FDA is proposing to allow dairy
processors and other food manufacturers to use new
label language to promote the health benefits of cal-
cium. Currently, a sample claim is ‘‘Regular exercise
and a healthy diet with enough calcium helps teen and
young adult white and Asian women maintain good
bone health and may reduce their high risk of osteo-
porosis later in life’’. Under a proposed new rule, milk
cartons, yogurt packages and even some fat-free
cheeses could soon display wording to the effect that
Vitamin D and calcium can help reduce the risk of
osteoporosis and promote bone health.
However, there is still the continued debate on the
benefit of consuming the large amounts of calcium
currently recommended for adults. Countries with
high calcium intakes such as America and Sweden
have some of the highest rates of osteoporosis. In
contrast, countries such as the Gambia, China, Peru
and India, have a much lower fracture incidence,
despite an average calcium intake of 300mg/d, less
than a third the amount recommended in the USA.
Differing dietary, genetic and lifestyle factors, includ-
ing physical activity and sun exposure may account for
the low fracture rate, but there are some thoughts that
the differences are related to high intakes of animal
protein, of which diary is included. High protein
increases the acid load in the body. In order to neu-
tralize the acid, the body pulls calcium from bones,
which may increase bone loss and increase the risk of
osteoporosis. As such there are thoughts that the focus
of the guidelines should be aimed at encouraging
everyone to eat more calcium-rich plant-based foods,
instead of consuming more dairy foods. Fruits and
vegetables are considered alkali rich foods that do
not need neutralizing and as such are more beneficial
to bone health. In addition, they are low in calories,
full offiberandantioxidants. As of 2007, recommen-
dations are that more studies are needed to understand
the consequences of this acid- base balance for skeletal
health in the long term.Resources
BOOKS
Brown, Susan E.Better bones, Better Body: beyond Estrogen
and CalciumMcGraw-Hill; 2 edition (April 1, 2000).
This book looks at osteoporosis from a wider perspec-
tive that includes lifestyle and exercise. It includes an
osteoporosis risk assessment questionnaire and a step-
by-step program for strengthening bones and improv-
ing overall health and well-being.
PERIODICALS
Celia J Pryrme, Gita D Mishra, Maria A O’Connell,
et al.‘‘Fruit and Vegetable Intakes and Bone Mineral
Status: A Cross-Sectional Study in 5 Age and Sex
Cohorts’’American Journal of Clinical Nutrition2006,
83: 1420-1428
Park SY, Murphy SP, Wilkens LR, Nomura AMY, Hen-
derson BE and Kolonel, LN. ‘‘Calcium and Vitamin D
Intake and Risk of Colorectal Cancer: The Multiethnic
Cohort Study’’American Journal of Epidemiology2007,
Volume 165, Number 7, Pages 784-793QUESTIONS TO ASK YOUR
DOCTOR With a family history of osteoporosis, should I
take a calcium supplement?
Do I need to take a Vitamin D supplement if I
avoid sun exposure?
If I don’t eat diary foods, how can I get enough
calcium in my diet?
Does eating too much protein increase my risk of
osteoporosis
Will too much dairy cause kidney stones?Osteoporosis diet