Before their bones weakened, all osteoporosis patients had very strong bones, like everybody else. All people in whatever country on whatever diet, are perfectly able to build strong bones. Everybody disposes of sufficient calcium to do so.
is not about the inability to build strong bones, but about
What makes the bones degenerate prematurely?
What enhances ageing of the bones?
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 old sooner. Excessive sun-exposure enhances ageing of the skin. It does so because the sun burns the outer skin cells, which have to be replaced by new cells sooner. And the sooner cells have to be replaced, the sooner the moment will be there that these cells cannot multiply anymore.
ageing of cells is about a higher turnover of cells; new cells replacing
old cells faster.
What makes old bones cells to be replaced by new ones sooner?
We know that estrogen is protective. (and androgens to a lesser extend) All bone-scientists acknowledge that if the female body disposes of sufficient estrogen all the time, osteoporosis risk is far lower.
That is why osteoporosis risk is 3-fold higher in women: In women every 4 weeks estrogen level is far lower, and are the bones less protected. And in post-menopausal women, estrogen level is structurally decreased.
If we know how exactly estrogen is protective against premature ageing of the bones, we also know how the opposite process enhances osteoporosis.
So, how exactly is bone-metabolism influenced by estrogen?
Estrogen both inhibits uptake of calcium into the bones (1) and deportation of calcium from the bones. (see Calcium Hormones) And because estrogen is protective, both absorbing and subsequently deporting less calcium is protective against osteoporosis. And therefore accelerated ageing of the bones is obviously about both absorbing and deporting too much calcium.
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 estrogen (2), production and activity of both osteoblasts and osteoclasts is increased. (3) (Like in hyperparathyroidism) If much calcium is absorbed, much calcium is deported. But with all new matrix that is composed, 50 to 70% of the composing osteoblasts die. (4) The more their activity is stimulated, the more they die (5). And because estrogen inhibits uptake of calcium, estrogen prevents death of osteoblasts (6).
If you consume much calcium all your life, reproduction of osteoblasts maybe increased all your life; many people succeed in increasing bone-mineral density by consuming more calcium. (7) That is why average BMD in people in countries where much milk is consumed, is higher.
Since the number of times cells can reproduce is fixed, reproduction capacity will be exhausted sooner if always much calcium is absorbed. And if reproduction 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 there is no new bone. Because old bone is decomposed to be replaced by new bone, porous holes will originate if there is a lack of pre-calcified bone matrix.
And this is exactly what happens in osteoporosis: In osteoporotic bone, the osteoblasts cannot sufficiently reproduce anymore, and thus less osteoblasts are available. (8) And/or activity of osteoblasts is at least impaired. (9) Like ‘exaggeratedly aged’ bones. (10) And thus in osteoporotic bones there is less matrix available that can yet be calcified, than in healthy bones. (11) In osteoporosis, dead cells cannot be replaced and micro-fractures cannot be repaired. (12)
Does that mean that dietary calcium causes osteoporosis?
Only if too much calcium is actually absorbed into the bones.
Like with all minerals, normally, the body just absorbs as much calcium from our food as it needs. Whether we consume 300 or 700 mg in total, or sometimes even when taking 1200 mg supplementary calcium daily; averagely only about 200 mg is absorbed into the blood. (13) To absorb the right amount of calcium, absorption rate decreases as we consume more calcium.
But if we consume too much calcium, 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. (14)
But why is this extra calcium absorbed in the bones?
Too prevent blood-calcium level from increasing too much.
Muscles can only function if calcium from inside the muscle cells can be deported outside the cells. And if blood-calcium level is too high, this is not possible, which would be lethal, since breathing requires muscle-action. To save your life, excessive dietary calcium is temporarily stored into the bones, prior to excretion. Normally the blood contains a total of 500mg calcium. The difference between highest and lowest blood-calcium level is only 26%, thanks to the 3 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 indeed hold on that extra calcium, but…
Like a house, our bones are built according to a plan. And the amount of calcium in the bones has to be according to that plan. Like piling up bricks in your living room does 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 keep much 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 had to process 2.9 million mg calcium more during these 40 years.
And since all this extra calcium is absorbed due to the action of osteoblasts, these osteoblasts die sooner, which leaves you with too little new bone-matrix and porous holes once you are old. Like administration of corticosteroids can cause osteoporosis for killing osteoblasts (15) ; both prematurely exhaust reproduction capacity. If little calcium is consumed, the bone-cells age slower, like a low calcium intake through adolescence has been shown to both retard and prolong longitudinal bone growth in rats. (16)
So, yes you can increase your bone mineral density (BMD) by consuming much calcium, but that will exhaust your bones sooner. That is why in those countries where average BMD is highest, 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 calcification of bone-matrix. (17) The only difference will be that the bones do not contain redundant calcium, and do not age prematurely.
But as the result of exhausted osteoblasts; no. Because holes do not contain calcium, in osteoporosis BMD is decreased due to the lack of new bone-matrix.
So, BMD can be low in very strong bones and in weakened bones, which is what makes it so confusing for so many scientists.
The problem of osteoporosis, is that it is a life-time process; it takes a lifetime to study a lifetime process.
Until now, studies about the lifetime effect of calcium on osteoporosis never covered more than a few years. And because increased calcium intake increases bone-mineral density, they concluded that calcium is protective. See Bone Mineral Density and Osteoporosis
But that is like concluding that the sun is protective against ageing of the skin because you ‘look better’ with a nice tan. While sun exposure actually enhances ageing of the skin. This may not seem so when you are young, but you will definitely notice so once you get older.
Furthermore, these studies also comprised less than 1500 subjects. (18) Or the data showed that those who absorbed less calcium in the bones, had a higher bone-fracture risk (19), while this decreased capacity to incorporate calcium in the bones was very likely due to exhaustion of osteoblasts.
In many other studies, no correlation was found between calcium consumption and hip-fracture risk in men or women (20), or was concluded that “high calcium intake did not protect against hip fracture”. (21)
A recent 12-year prospective study among 77,761 women revealed that consuming milk increases bone-fracture risk. (22) Two other studies 'unexpectedly' did the same. (23)
But is there no other way to find proof?
Yes there is.
Nobody can explain, but until now, they have not published any studies about the lifetime effects of calcium supplementation in mice or rats. Maybe they did not like the results?
Luckily, there is another way;
Compared to other foods, only dairy products can be consumed in such large quantities on a daily base, that this strongly increases calcium intake. And there are statistics about average milk (-products) consumption per country. Like there are statistics about hip-fracture incidence per country.
If extra calcium is protective, in those countries where people are used to drinking lots of milk all their life, hip-fracture / osteoporosis incidence must be lowest.
It is verysimple ; where most milk is consumed, osteoporosis incidence is highest. Compared to other countries, in Sweden, Finland, Switzerland and The Netherlands most milk is consumed (300 to 400 kg / cap / year), and skyrockets osteoporosis incidence. (28)
Like Australians and New Zealanders (29), Americans consume 3 fold more milk than the Japanese, and hip-fracture incidence in Americans is therefore 2½ fold higher. (30) And in those within America that consume less milk, like the Mexican-Americans and Black Americans, osteoporosis is two-fold lower than in white Americans (31), which is not due to genetic differences. (32)
Chinese consume very little milk (8 kg / year), and hip-fracture incidence therefore is among the lowest in the world ; hip-fracture incidence in Chinese women is 6 fold lower than in the US. (33) (Americans averagely consume 254 kg milk / year)
The less milk is consumed, the lower osteoporosis rates are. (34)
In other countries where averagely very little milk is consumed, like in Congo (35), Guinea (36) and Togo (37) (6 kg / year) osteoporosis is extremely rare too.
In the Dem. Rep. Congo, Liberia, Ghana, Laos and Cambodia even less milk is consumed (average person: 1 to 3 kg a year !!), and they've never even heard of age-related hip fracture.
And of course, 'they' will say : "that's because blacks and Asians are genetically different from whites", but that is rubbish ; Osteoporosis incidence in female Asians is much lower than in Asian females living in the USA. (38) Like osteoporosis incidence (and calcium consumption) in African Bantu women (39) is much lower than in Bantu women living in the USA. (40) Like both calcium intake and hip-fracture rate is far lower in South African Blacks than in African Americans. (41)
Alternative hypothesises about osteoporosis incidence;
''Nature has made a mistake but fortunately we are smarter than nature, and know how to correct this ; By mistake mother's milk contains far too little calcium, what has to be corrected through giving cow's milk to humans, containing 4 times as much calcium.''
Of course this is nonsense.
If calcium requirements really were 4 fold higher, pre-historic infants would never have been able to grow up, and have kids ultimately. If we really need cows milk, man could never have existed.
Because we already are on this planet for millions of years. And we only consume milk since a maximum 0,01 million years. This means that we did not drink a single drop of milk from other animals in more than 99% of human existence ; in our entire development from ape to modern human being, we never drank, nor needed milk.
1.6 million years ago, there already were way over 6 feet tall humans (42), with apparently strong bones.
So, exactly how much calcium does mothers' milk contain ?
Calcium in mg / 100 g
140 Egg yolk
96 Olives, green
44 Black berries
32 Human milk
What does this mean ?
Adults and infants always need less calcium than babies (per kg bodyweight). Food for adults therefore does not need to contain as much calcium (in %) as mother’s milk.
And because our natural foods averagely contain about as much calcium as mother's milk, it is absolutely impossible that these natural foods contain too little calcium.
If they would, mother’s milk would contain too little calcium too, and babies would not be able to increase BMD on mother’s milk.
And because many foods contain more calcium than mother’s milk, average calcium absorption rate is low, to prevent uptake of excessive calcium.
Some say osteoporosis incidence is therefore higher in countries with little sunlight.
However, if you consume some fish and / or egg yolk every once and a while, you'll absorb all the vitamin D you need, even living in Greenland, Canada or Northern Europe.
Is osteoporosis incidence really lower in countries with more sunlight?
Not necessarily; though Italy is much sunnier than Poland, hip-fracture incidence in Italy is much higher (43) than in Poland (and Spain) (44), simply because in Italy 50% more dairy products are consumed. (24) Kuwait is extremely sunny, but nevertheless osteoporosis incidence in Kuwait is about as high as in Great Britain and France (38), because in Kuwait also lots of milk is consumed. (24)
Furthermore, the effects of this vitamin D-hormone can be very different;
Directly, this hormone increases calcium absorption from food and absorption of calcium into the bones (45), and therefore induces death of osteoblasts (46). Calcitriolalso stimulates deportation of calcium from the bones into the blood. (see ; the “Calcium-hormones”)
On the other hand, this hormone also inhibits secretion of PTH, while excessive PTH strongly accelerates ageing of the bones. (see hyperparathyroidism) Thus, indirectly, this hormone can be protective, per saldo decreasing both uptake of calcium into the bones and deportation of calcium from the bones. (47) (see the “Calcium-hormones”)
However, since supplementary vitamin D / calcitriol increases blood-calcium level (48), this extra calcium can precipitate in arteries and on the outside of the bones (causing arteriosclerosis and bone-deformities (49)), joints and ligaments, and can cause muscle-cramps (since blood-calcium level needs to be low enough to deport calcium from muscle cells) and even kill muscles cells (if the calcium structurally cannot be deported), eventually causing fibromyalgia.
Mostly, osteoporosis is not accompanied with a lack of vitamin D. On the other hand, it often does (50), but this can have multiple causes;
·Consuming too much calcium causes both erosion of the bones and can strongly decrease calcitriol level because secretion and decomposition of hormones regulating blood-calcium level, is increased when much calcium is absorbed. The body has no problem composing more of those other calcium-hormones, but calcitriol is composed of vitamin D, which availability may be limited.
·Hyperparathyroidism strongly increases both uptake of calcium into the bones and deportation from the bones, eventually causing osteoporosis. If too little calcitriol is available, secretion of PTH is not sufficiently inhibited.
·If really very little calcium is consumed (less than 300 mg / day, which is a very hard thing to achieve), a lack of vitamin D / calcitriol can cause osteoporosis for making it impossible to increase calcium absorption.
In general, it is not a problem at all to dispose of little vitamin D / calcitriol, for protecting us against absorbing too much calcium.
In 52% of examined Saudi Arabian females for example, vitamin D level was extremely low (because of clothes that block almost all sunlight), but their bones were not affected. (51)
In alcoholics levels of the vitamin D-hormones were decreased with 23 to 48%, but BMD was not affected. (52)
In general we do not need much vitamin D to either inhibit PTH secretion or increasing calcium absorption.
And because exercise increases BMD, couldn’t osteoporosis be due to a lack of exercise?
They simply forgot that BMD is lowest in countries where osteoporosis incidence is lowest too. And that a lack of exercise decreases BMD, but does not cause spongous holes.
Osteoporosis is quite common in female athletes for example, because intense physical exercise makes the body produce less estrogen. (53)
The reason is that by increased burdening of the bones, bone-cells are destroyed, which stimulates the bones to increase strength, to be better able to cope with future loads. To make this possible, more calcium is absorbed into the bones (increasing death of osteoblasts (54)), and less is deported. But amenorrhea is a common problem in female athletes, while estrogen is required to decrease the deportation of calcium.
This is the reason why exercise can never ‘compensate’ the side effects of reduced estrogen levels (55) ; exercise increases deportation of calcium from the bones (due to cell-damage), while increasing bone mineral density requires an decrease in calcium deportation, and that is where the estrogen is required for.
And since the exercise itself increases deportation of calcium from the bones, exercising too intensively is detrimental. (56)
Like muscle power can be increased through exercise, bone strength can too. And like pumping up your muscles when you are young does not make you an Arnold Schwarzenegger when you are 80, exercise at young or adult age does not guarantee future bone strength. (57)
Bone strength is determined by your current daily activities, like the volume of your muscles is. And like with your muscles, the bones can handle a fall or unusual action. That is all ‘part of the plan’.
Most old women with osteoporosis have been working very hard all of their life, and were still normally active when they were diagnosed with osteoporosis. So the osteoporosis could never be caused by a lack of exercise.
Exercise can be effective for the treatment for osteoporosis though (58), because of the protective effect of muscle contraction (59), and it might even increase strength in the remaining intact part of the bones.
© 2000 Copyright Artists Cooperative Groove Union U.A.
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