Excessive Calcium Causes Osteoporosis
The older you get, the higher your risk of osteoporosis.
Obviously, osteoporosis is about aging.
Osteoporosis patients originally had very strong bones, like everybody else.
Osteoporosis is not about the inability to build strong bones, but about premature degeneration of the bones.
Can My Bones Be Tested?
For some people the first sign of osteoporosis is to realize they are getting shorter or to break a bone easily.
A bone density test can find out how solid your bones are. If you are age 65 or older, taking a bone density test called a DEXA-scan (dual-energy x-ray absorptiometry) can tells what your risk for a fracture or broken bone is, or it could show that you have normal bone density. Or, it could show that you have low bone mass or even osteoporosis.
All our organs age. In all our organs cells constantly reproduce themselves; they wear out and are replaced by new ones. And because the number of times cells can multiply is fixed, organs eventually age. Like the skin eventually becomes wrinkled when there are less cells available to replace the dehydrated old skin-cells.
We all know that if we expose our skin to the sun too much, that we will look older sooner. Excessive sun-exposure accelerates the aging of the skin. It does so because the sun burns the outer skin cells, which must be replaced by new cells sooner. And the sooner cells must be replaced; the sooner the moment will come that these cells cannot multiply anymore.
Accelerated aging of cells is about a higher turnover of cells; new cells replacing old cells more frequently.
Medicines. Some common medicines can make bones weaker. These include a type of steroid drug called glucocorticoids used for arthritis and asthma, some antiseizure drugs, certain sleeping pills, treatments for endometriosis, and some cancer drugs.
An overactive thyroid gland or using too much thyroid hormone for an underactive thyroid can also be a problem.
Lifestyle. Smoking increases loss of bone mass. For this and many other health reasons, stop smoking. Limit how much alcohol you drink. Too much alcohol can put you at risk for falling and breaking a bone.
What causes old bone-cells to be replaced by new ones sooner?
We know that estrogens are protective. (and androgens to a lesser extent) All bone-scientists acknowledge that if the female body has sufficient estrogens at its disposal all the time, osteoporosis risk is far lower.
That is why osteoporosis risk is 3-fold higher in women: In women, the estrogens level is far lower every 4th week and the bones are less protected at that time. And in post-menopausal women, estrogens level is permanently decreased.
If we knew exactly how estrogens protect against premature aging of the bones, we would also know how the opposite process enhances osteoporosis.
So, how exactly is bone-metabolism influenced by estrogen?
Estrogens inhibit both the uptake of calcium into the bones and deportation of calcium from the bones.
But how exactly can processing more calcium cause osteoporosis?
The absorption of calcium requires the activity of specialized cells: osteoblasts. These osteoblasts also compose pre-calcified bone-matrix, upon which the calcium can precipitate.
Deportation of calcium from the bones requires the activity of osteoclasts.
If more calcium is absorbed into the bones, like due to a lack of estrogens, the production and activity of both osteoblasts and osteoclasts is increased (as in hyperparathyroidism).
If much calcium is absorbed, much calcium is deported. But 50 to 70% of the composing osteoblasts die in the composition of new matrix. The more their activity is stimulated, the more they die. And since estrogens inhibits uptake of calcium, estrogens prevents the death of osteoblasts.
If you consume higher amounts of calcium all your life, the replacement of osteoblasts maybe increased all this time; many people succeed in increasing bone-mineral density by consuming more calcium. That is why the average BMD is higher in residents of countries where much milk is consumed.
Since the number of times a cell can be replaced is fixed, the replacement capacity will be exhausted sooner if much calcium is absorbed on a regular basis. And if replacement capacity is exhausted, there will be a lack of new osteoblasts.
And since only these osteoblasts can compose bone-matrix, too little new bone-matrix can be composed. But without the matrix, the calcium cannot precipitate, and new bone cannot be composed, while old bone is constantly being decomposed anyway, to be replaced by new bone. Since there is a lack of pre-calcified bone matrix upon which to build, replacement cannot occur, and porous holes will begin to appear.
And this is exactly what happens in osteoporosis: in osteoporotic bone, the osteoblasts cannot be replaced adequately anymore, and thus less osteoblast is available and/or the activity of osteoblasts is at least impaired, like "exaggeratedly aged" bones.
In osteoporotic bones there are fewer matrixes available that can yet be calcified than in healthy bones. In osteoporosis dead cells cannot be replaced and micro-fractures cannot be repaired.
Does that mean that dietary calcium causes osteoporosis?
Only if too much calcium is actually absorbed into the bones.
As with all minerals, the body normally absorbs just as much calcium from our food as it needs.
Only about 200 mg is absorbed into the blood, on the average, whether we consume 300 mg or 700 mg calcium daily, or sometimes even when we consume up to 1200 mg supplementary calcium daily.
In order to absorb the right amount of calcium, absorption rate decreases when we consume more calcium.
But if we consume too much calcium, the absorption rate cannot be sufficiently decreased; about 5% of dietary calcium on top of 1500 mg a day is yet absorbed into the blood.
For example: Consuming 5-fold more calcium than before, a group of girls did, in fact, absorb twice as much calcium (as before) into the blood.
But why is this extra calcium absorbed in the bones?
This is to prevent blood-calcium level from rising too much.
Muscles can only function if calcium from inside the muscle cells can be deported outside the cells. If blood-calcium level were too high, this would not be possible; it would be lethal since breathing requires muscle-action.
To save your life excessive dietary calcium is temporarily stored in the bones, prior to excretion. Normally the blood contains a total of 500 mg calcium. The difference between highest and lowest blood-calcium level is only 26%, thanks to the three different hormones that prevent our blood from containing too much (or too little) calcium.
After the calcium has been absorbed into the bones, two of these hormones stimulate deportation of calcium from the bones, and the third one stimulates excretion of calcium into urine.
But why don't the bones hold on to that extra calcium?
According to the old doctrine, we can prevent osteoporosis by stacking more calcium in the bones.
"The more calcium your bones contain, the longer it will take before they are empty"
This would be a simple solution if the bones did indeed hold on to that extra calcium, but.........
Our bones are built according to a plan - just like a house, and the amount of calcium in the bones has to be according to that plan. Just as piling up bricks in your living room do not make your house better or stronger, stacking extra calcium in the bones is not an improvement either. To be able to watch TV and clean your house properly, you throw the bricks out.
The redundant calcium in your bones is always deported eventually. To preserve redundant calcium in your bones, you have to keep on consuming lots of calcium daily.
But no matter how much milk you drink, or supplementary calcium you take (or not at all), your bones always contain less calcium at the age of 70 than at the age of 30.
The problem is that all this extra calcium is processed by osteoblasts and osteoclasts. If you have been absorbing 400 mg instead of 200 mg dietary calcium into the blood daily, these cells have had to process 2.9 million mg more calcium during these 40 years.
Since all this extra calcium is absorbed due to the action of osteoblasts, these osteoblasts die sooner, leaving you with too little new bone-matrix and too many porous holes once you are old.
Similarly, excessive vitamin A, and also the administration of corticosteroids and elevated cortisol levels can cause osteoporosis by killing osteoblasts; all prematurely exhaust the capacity to produce new osteoblasts.
If less calcium is consumed, the bone-cells aged slower and a low calcium intake throughout adolescence has shown to both retard and prolong longitudinal bone growth in rats.
Therefore, you can increase your bone mineral density (BMD) by consuming much calcium, but that will exhaust your bones sooner.
Yes, a high BMD means (temporarily) stronger bones, but not healthier bones. Just as bodybuilders have stronger muscles, but not healthier muscles. Actually, as they grow older, they experience more muscle problems.
The same is true for the bones; the more their aging is accelerated, the sooner their bone modelling capacity will be exhausted
That is why in those countries where the average BMD is highest; the hip fracture incidence is highest too.
Does this mean that a low BMD is preventive?
If BMD is low because you consume little calcium all your life, yes.
If calcium intake is very low, there will still not be a lack of calcium for the calcification of bone-matrix. The only difference will be that the bones will not age prematurely, and that they will not contain redundant calcium.
But if the BMD is low as the result of exhausted osteoblasts; NO.
BMD is decreased in osteoporosis due to the lack of new bone-matrix. Holes do not contain calcium.
So BMD can be low in very strong bones and in weakened bones, which is what makes it so confusing for so many scientists.
Supplementary calcium / milk have short term 'beneficial' effects on bone-mineral density (BMD) and adverse long-term (lifetime-) effects.
One can increase BMD by a high-calcium intake or not.
The average short-term effect of extra calcium is the increase in bone-mineral density, and thus strength. That is why average BMD is highest in those countries where much milk is consumed.
If you investigate this correlation, extra calcium will have 'beneficial' effects on bone-strength or not.
But this does not say anything about the lifetime effects; it just confirms what initially happens if you consume much calcium; this is just the first effects, not the eventual result.
The above opinionated views and information serves to educated and informed consumer . The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. .It should not replaced professional advise and consultation. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions
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