Vegan and Vegetarian Diets and Calcium
I receive many emails and letters from people worrying themselves about their Ca intake when they switch to being vegetarian or vegan. They think that if they give up dairy, they will not get enough Ca in their diets. However, the reverse is true, in fact it is my belief that drinking milk and eating dairy products contributes to the disease called osteoporosis! The way that dairy is now processed causes a change in the actual molecule of the milk causing it to be a much larger molecule which cannot pass through the system so it is stored in the fat cells. Many scientists now also believe that this mutant molecule is a cause of things like Alzheimer's disease!
We can get all the CA (500 mg per day) we need from a vegetarian diet. And the Ca from vegetable sources is far higher quality than that from milk. The bad side effects of dairy are well documented by myself and many others nowadays. I have been telling people about this for many decades.
Examples of amounts of foods providing 100mg calcium
Type of Food
Protein & Calcium
A high protein diet, especially derived from animal foods, causes calcium loss in the body. The higher sulphur-to-calcium ratio of meat increases calcium excretion, and a diet rich in meat can cause bone demineralisation. A report published in 1988  comparing the amounts of calcium excreted in the urine of 15 subjects showed that the animal-protein diet caused greater loss of bone calcium in the urine (150mg/day) than the all-vegetable protein diet (103mg/day). These findings suggest that diets providing vegetable rather than animal protein may actually protect against bone loss and hence osteoporosis. In one study adults on a low-protein diet were in calcium balance regardless of whether calcium intake was 500mg, 800mg or 1400mg a day.  Interestingly The American Dietetic Association, in its 1993 policy statement on vegetable diets, pointed out that the calcium intakes recommended in the USA were increased specifically to offset calcium losses caused by the typically high protein consumption in that country.
Only 20-30% of calcium in the average diet is absorbed. Calcium absorption can be reduced because it binds to fibre, phytate or oxalate in the intestine. Vegan diets contain more than average of these substances. Fibre is no longer thought to limit the availability of calcium from food. Phytate or phytic acid is found in grains, nuts and seeds and can bind with calcium making it less absorbable. However, the body does adapt to lower levels of available calcium and the American Dietetic Association and the UK's Ministry of Agriculture, Fisheries & Foods as well as the Department of Health believe that fibre, phytate and oxalate do not have a significant effect on calcium intake overall.
Although the calcium intake of adult vegans tends to be lower than the recommended optimum, it is close to the Estimated Average Requirement. There have been no reports of calcium deficiency in adult vegans.
The Estimated Average Requirement (UK) of a nutrient in the diet is an estimate of the average needs of a group of people. About half may need more, and half may need less.
Osteoporosis is the major cause of bone fractures in the elderly. One in four British women are affected by this disease. It is better prevented than treated and prevention includes an adequate intake of calcium throughout life, but especially in childhood and young adulthood; and minimising major risk factors e.g. smoking, heavy alcohol use and lack of physical exercise. Diets high in protein and in salt (sodium chloride) also increase calcium loss from the body and may have an effect on osteoporosis. Post-menopausal women are more prone to osteoporosis because they produce less oestrogen, which protects the skeleton in younger women.
There has been much publicity about the role of dietary calcium in preventing osteoporosis but the fact remains that it is more common in Westernised countries where calcium intakes and consumption of dairy products are high compared to the rest of the world. Osteoporosis is comparatively rare in rural subsistence cultures, even though calcium intakes are much lower. Lifestyle factors, such as physical activity, lower protein intakes, little alcohol consumption and the rarity of smoking, may offer protection to people in these populations.
Cow's Milk & Health
The advertising blurb surrounding cow's milk would make anyone think it is an absolutely essential and natural product for humans. Most people when thinking of increasing their calcium intake would immediately reach for a carton of milk or slab of cheese. However, there are several reasons for not using these products as a nutrient source. Whole cow's milk is suited to the nutritional needs of calves who double their weight in 47 days and grow to 300 pounds within a year. In fact, human beings are the only species to drink the milk of another species, and the only species to drink milk beyond infancy. In addition about 90% of the world's adult population (in Britain the figure is probably 25%) is deficient in the enzyme needed to digest milk properly. The enzyme lactase is present in infants for digesting their mother's milk, but levels decline after the age of five years. Adults who lack the enzyme suffer from bloating, cramping, wind and diarrhoea if they drink milk.
The most significant connection between milk and ill-health is probably through its contribution to heart disease. Too much saturated fat in the diet can lead to atherosclerosis, where the arteries 'fur up' with cholesterol deposits and cannot deliver enough blood to the vital organs. The heart is particuarly susceptible. Milk and other dairy products account for about half of all saturated fats eaten in this country. Meat accounts for the rest. The UK has the highest level of heart disease in the world.
Child-care expert Dr Benjamin Spock, once an advocate of drinking cow's milk, has joined several doctors questioning its nutritional value and warning of a possible link to juvenile onset diabetes and allergies. "Breast-feeding is the best milk feeding for babies," says Dr Spock. Dr Spock is backed up by Dr Frank Oski, director of pediatrics at John Hopkins University and Dr Neal Barnard, president of the 2000-member Physicians' Committee for Responsible Medicine. Dr Oski states that cow's milk is overrated as a source of calcium, is often contaminated with traces of antibiotics, can cause allergies and digestive problems and has been linked to juvenile diabetes. 
Vegans need to get at least 500 mg of calcium from calcium rich foods, such as tofu, fortified milks and greens, or supplements. Together with calcium from other less concentrated sources, this would give an overall calcium intake between 700 mg per day and 1000 mg per day. There is very little evidence that higher intakes than this would be beneficial.
However, bone health is about much more than calcium. The fact that osteporosis risk is high in countries consuming relatively high amounts of calcium/dairy products illustrates this. Studies comparing individuals within developed countries also indicate that the benefit of calcium alone for reducing fracture risk is modest. Vitamins D and K may be more important while potassium (fruits, vegetables, roots and beans) reduces calcium losses and bone turnover and sodium (salt) increases these. Moderate, rather than low or high, protein intake is probably best. Physical activity plays a vital role. The best approach to prevention takes all these factors into account.
Dumb Comment, Dumb Study, Dumb Conclusion, Smart Ending
"Fruits and vegetables are generally
a pretty low source of calcium."
--Jay Norris, Baylor College of Medicine
Just for the record...a 100-gram portion (3.5 ounces) of
human breast milk contains 33 milligrams of calcium. Is
human breast milk considered a low source of calcium?
That same 100-gram portion of:
Carrots (raw) = 37 mg of calcium
Potato Chips = 40 mg of calcium
Oranges (Florida) = 43 mg of calcium
Apricots (dried) = 67 mg of calcium
Lettuce (dark green) = 68 mg of calcium
Figs (dried) = 126 mg of calcium
Parsley = 203 mg of calcium
Collards (raw leaves) = 250 mg of calcium
So, since 33 mg of calcium per portion of breast milk is
lower than any of the fruits and veggies on my list which
Dr. Norris collectively calls "a pretty low source of calcium"
then human breast milk must not be a proper enough food for a
nursing infant to grow strong bones. Please select one of the
two following conclusions: Either Mother Nature is a dummy,
or Doctor Norris is a poorly informed ignorant fool.
(Proceedings of the National Academy of Sciences
online edition January 14, 2008)
After commenting that vegetables are a low source of
calcium, Dr. Norris proceeded to test calcium excretion
rates on human subjects who had just eaten...a veggie.
Dr. Norris fed regular carrots and genetically modified
(GMO) carrots to 15 men and 15 women and then tested
their urine for calcium. He determined that those eating
the GMO carrots excreted less calcium, concluding that
they absorbed more calcium.
The body needs about 90 days to build new bone. One
does not build new bone after eating a carrot. After
measuring urine excretion rates, Dr. Norris assumed
that the calcium which was not excreted was used by the
body to build bone. In fact, that very calcium might
have been used to build athersclerotic plaque, kidney
stones, or cellulite.
Individual subjects eat different diets. Some might have
been eating more calcium at home than the body required.
People do so by bulking up on concentrated dairy products
such as cheese and ice cream.
Excess calcium is sometimes excreted in the urine and
other times used by the body in ways that do not
benefit the individual.
The average American woman eats 1180 milligrams of
calcium each day.
The average South African woman eats
just 80 milligrams of calcium each day.
American women have 11.5 times the rate of pelvic
fractures as do South African women, despite the
fact that they consume 1,500 percent more calcium.
Source: The Okinawa Diet Plan by Wilcox, Wilcox, & Suzuki.
Quote by a well-known carrot eater:
"Eh...what's up, doc?"