Dont Listen to This Osteoporosis Lie
Calcium is still being treated as the cure-all for osteoporosis. The entire Got milk? campaign is a testament to the strength of the belief that calcium strengthens the bones. But there is hardly any evidence to support this lie. What studies show is that calcium improves bone mass when combined with certain other minerals and vitamins. What other minerals and vitamins are required for calcium to improve bone health? Why is high-dose calcium supplementation dangerous and how can you improve bone strength? Read on to find out.
by Brad Chase
Calcium is mostly known as the mineral essential to bone health. The public and most of the medical community believe that it is essential to the development of strong, dense bones early in life and to the maintenance of healthy bone density in adulthood.
However, calcium also plays other roles in the body. It is essential to muscle contraction, electrical conduction in nerves and to the release of neurotransmitters in the brain.
Milk and dairy products are the most popular sources of calcium but, for those with lactose intolerance, there are other excellent sources too.
Good sources of calcium include green, leafy vegetables such as kale and broccoli (vegetables such as spinach and chard have high calcium content but their high oxalic acid contents make the calcium mostly unavailable).
Other good sources of calcium include egg shell, seaweeds (kelp, wakame etc.), nuts and seeds (almond, sesame, hazelnut etc.), beans, figs, okra and molasses.
Calcium can also be found in fortified foods such as calcium-enriched orange juice and soy milk.
Calcium supplements are primarily used to treat calcium deficiency and also to improve bone health.
There are a number of these supplements including inorganic salts and organic salts. The 4 most common calcium supplements are calcium carbonate, calcium citrate, calcium gluconate and calcium lactate. Of these, calcium carbonate provides the highest proportion of elemental calcium.
Health experts recommend taking calcium supplement with meals and not to take more than 500 – 600 mg at once. These precautions ensure increased bioavailability of calcium from these supplements.
This is especially important for those who take high doses of calcium supplements. Women, especially postmenopausal women, regularly take megadoses of calcium supplements daily in the hope of lowering their risks of bone fractures and in the treatment of osteoporosis.
How effective is the use of calcium supplements to strengthen bones? According to studies, not very.
Calcium supplementation is not only ineffective for lowering the risks of bone fractures but there is good evidence to suggest that it may also be harmful to your health.
Although calcium supplements are recommended for preventing bone fractures caused by osteoporosis, the truth is that there is no solid scientific evidence to back up this recommendation.
Ideally, the body closely regulates the amount of calcium it uses and stores. Because calcium gets into the body through food, the body eliminates as little as 100 mg of the mineral every day and keeps rich stores in the bones and teeth.
When the blood level of calcium falls or when there is an urgent demand for calcium elsewhere in the body, some of the calcium stored in the bones are taken to meet the pressing need.
However, because calcium is the major mineral making up the bones, the medical community oversimplified the link between calcium and bone strength and blindly recommended increased calcium supplementation for people suffering from osteoporosis.
This oversimplification created a calcium myth, a widespread belief in the power of calcium to improve bone health.
There are a number of things wrong with this theory. First, calcium is not the only mineral making up the bones. There are at least a dozen other minerals found in the bone including magnesium, zinc and even fluoride. Therefore, simply loading up on calcium can lead to a disproportionate bone mineral composition.
In addition, high dose calcium supplementation reduces the absorption of iron and zinc.
Secondly, calcium is not the only factor required for the proper mineralization of bones. Proper mineralization of the bone also requires magnesium, phosphate, vitamin D3 and vitamin K2.
Both vitamins D and K help move calcium from the blood to the bones. Therefore, they promote the incorporation of calcium into bones.
Of the two vitamins, vitamin K2 is definitely the more important. Studies show that the combination of calcium and vitamin D does very little to reduce the risk of bone fractures. However, when vitamin K2 is added, there is a significant reduction in the incidence of osteoporotic fractures.
So, how does vitamin K2 improve the combination of calcium and vitamin D? By preventing the deposition of calcium on the walls of arteries as well as on organs, soft tissues and in bone joints.
In addition, vitamin K2 stimulates the production of the protein known as osteocalcin from osteoblasts, the cells that make up the bones. Osteocalcin is required to bind calcium to bones.
High-dose calcium supplementation may increase bone mineral density but it does not give the bone tensile strength.
There is a difference between bone mineral density and bone strength. The confusion between the two terms arises from the inappropriate determination of mineral density in bone tests. By regarding the T-score of the bones of a youth as the standard, bone tests do not account for changes that occur to the bone as we age.
Therefore, most adults are classified as osteoporotic and promptly placed on high-dose calcium supplementation.
Calcium may increase bone density but that only shows a measure of the compressive strength of bones.
The relevant measure is tensile strength because it reflects the ability of bones to contract and expand while restricting breakage. Unfortunately, calcium supplementation does not improve the tensile strength of bones (weight-bearing exercise does).
It is no wonder then that megadoses of calcium do not lower the risk of osteoporotic bone fractures.
Multiple studies and meta-analyses have found that increasing the blood level of elemental calcium can raise the risk of cardiovascular disease, heart attack and stroke.
In one review involving over 8,000 participants, it was demonstrated that those taking 500 mg/day and above of calcium supplements had 27% higher risks of heart attack than those who did not. Another meta-analysis published in JAMA Internal Medicine and involving 12,000 men concluded that 1,000 mg/day of calcium supplement increased the risk of cardiovascular disease by 30%.
Some experts have argued back that combining vitamin D with calcium will reduce the risk of heart attack but a more recent review found that assertion to be untrue.
The review showed that the combination of calcium and vitamin D raised the risk of heart attack by 24% and also increased the combined risk of heart attack and stroke by 15%.
All of these results show that calcium supplementation is not only ineffective for reducing the risk of osteoporotic bone fractures but that it has a negative effect on the cardiovascular system.
So, how does calcium supplements increase the risk of heart attack and stroke?
It turns out that the answer is very straightforward. By raising blood calcium levels, calcium supplements increase the amount of elemental calcium moving around the body.
In the absence of factors such as vitamin K2 to drive calcium to the bones, the excess calcium in the blood deposited around the body as it is transported. Because free calcium travels in the blood, it is easily deposited in the walls of the arteries where it forms plaques.
This observation calls into the question the belief that the cholesterol deposited on artery walls is responsible for atherosclerosis and poor cardiovascular health. When examined, it was discovered that over 90% of arterial plaques are calcified.
While cholesterol is waxy, calcium is solid. Once deposited, it hardens cholesterol and the walls of the arteries.
Therefore, the calcification of arterial walls reduces the elasticity of arteries and serves as the root cause of all kinds of cardiovascular disease.
Calcium supplements raise the risk of heart attack and stroke because the calcified plaques on the artery walls can also break off easily and block blood vessels. Therefore, the increased risk of cardiovascular disease and stroke in the elderly can be directly traced to years of high calcium intake.
Another confirmed harmful effect of calcium supplementation is increased risk of prostate cancer.
The Physicians’ Health Study published in the American Journal of Clinical Nutrition in 2001 showed that men who consumed more than 600 mg/day calcium from dairy products had 32% higher risk of prostate cancer than those who consumed less than 150 mg/day of dairy calcium.
A 1998 study published in the journal, Cancer Research, also confirmed the link between prostate cancer and high calcium consumption.
Besides the walls of arteries, the kidney is another major site where calcium is preferentially deposited.
Therefore, calcium supplementation in the treatment of osteoporosis can lead to the formation of kidney stones.
Usually calcium supplements are not recommended for people with impaired kidney functions. However, there is evidence to suggest that high doses of calcium supplements can affect kidney functions even in people without previous kidney problems.
Calcium supplement can cause kidney stones because the body tries to excrete excess calcium through the kidneys.
A 2004 study published in the journal, Kidney International, investigated the effect of changing the schedule of calcium supplementation on the risk of kidney stone formation. The researchers found that urinary calcium oxalate levels were reduced when calcium supplements were given with meals but not when given at bedtime.
Therefore, they recommended that calcium supplements should be taken with meals in order to lower the risk of kidney stones.
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