Curios we should have such a hormone calcitonin to lower calcium levels but helps explains how important it is to keep the blood concentration within a narrow range. Calcitonin is excreted by the thyroid gland.
It lowers the blood calcium level by acting on the osteoclasts (perhaps osteoblasts) in skeletal bone to prevent bone break down, and the kidneys preventing calcium reabsorption. It essentially counters the effects of PTH. Of note having too little or much of this hormone appears to have no adverse effect. 1
Then there is magnesium. Which interesting as it has a higher concentration intracellularly and thus measuring blood levels can be misleading as to presence or absence of adequate amounts in the body. Magnesium is important in incorporating calcium into bone. Thus, inadequate levels can lead to excess loss of calcium.
Magnesium directly contributes to osteoporosis by acting on crystal formation, bone cells and indirectly by impacting the activity of parathyroid hormone (PTH) and promoting low grade imflamation.1 About 60% of our magnesium is store in our skeletal bones.2 Additionally magnesium antagonizes calcium.
Bones without adequate magnesium are brittle and fragile, probably by inhibiting osteoblast formation and increasing osteoclast formation. Again, as osteoblast build bone and osteoclasts break it down. So, you can see an imbalance could cause skeletal bone problems.
Low magnesium levels may also reduce the activity of the enzyme that produces the active form of vitamin D3, reduces secretion of PTH and/or makes the targets of PTH less receptive. Much of this through reduced production of the active form of vitamin D3. Thus, adequate vitamin D3 levels may be able to compensate for. Though an area for more study.
Another way that the body controls calcium levels is by the destruction of the active form of vitamin D3. This occurs several ways. One is fibroblast growth factor 23 and the other is a hydroxylase which initiated by higher levels of the active form of vitamin D3.3 The active forms concentration is tightly controlled. It is the blood form which causes issues with calcium and again only at high concentrations as discussed in earlier part of this series of posts.
Vitamin K2 is important in incorporating calcium into skeletal bone also. It has been shown to prevent arterial calcification and arterial stiffening. 4,5 We need a properly functioning gut to alter vitamin K1 which we typically in US diets receive more of then vitamin K2 which typically comes from fermented food. Think sauerkraut or miso. Otherwise our foods are bereft of it.
As I have discussed earlier the osteoclasts and osteoblasts effect bone formation and break down. Well vitamin K2 is necessary to activate osteocalcin. Osteocalcin helps take calcium from the blood and bind it to the bone matrix. 6
So, if you have reached this point and still with me, hopefully I have made it clearer. As perhaps it is none of these studies I have refenced nor any of my theories are correct. Often these studies show a correlation not a cause and effect. That calcium metabolism is complex and even the basic scientist doesn’t have it all worked out. I believe that osteoporosis like coronary artery disease should not exist. As both are thought to be two extremes on the spectrum of calcium. That is, one is too little and the other is too much. However, I think they are both the result of sub optimal blood levels of vitamin D3.
That the hormonal system has predominated resulting in the adequate mobilization of calcium but at the expense of bone health and immune system. I believe it takes the slow-active response that occur at higher vitamin D3 levels to rebuild the bones after active-fast response.
That chronic inflammation due to weak immune system again due to insufficient vitamin D3 such that the MH effects are not activated causing atherosclerosis in the arteries. The calcium only comes into play as the body is either mobilizing more skeletal bone then is rebuilt or in atherosclerosis the body is trying to calcify off the injured artery walls.
- Castiglioni S, Cazzaniga A, Maier JAM, et al. Magnesium and osteoporosis: Current state of knowledge and future research directions. Nutrients. 2013 Aug; 5(8): 3022-3033.
- Kidd PM. Vitamin D and K as pleotropic nutrients: Clinical importance of the skeletal and cardiovascular systems and preliminary evidence of synergism. Alternative Medicine review. 2010; 15(3): 199-222.
- Beulens JW, Bots ML, Atsma F, et al. High dietary menaquinone intake is associated with reduced coronary artery calcification. Atherosclerosis. 2009;203(2):489-493.
- Geleijnse JM, Vermeer C, Grobbee DE, et al. Dietary intake of menaquinone is associated with a reduced risk of coronary artery disease. The Rotterdam Study. J Nutr. 2004; 134(11):3100-3105.
- Hauschka PV. Osteocalcin: the vitamin K-dependent CA2+-binding protein of bone matrix. Haemostasis. 1986;16(3-4):258-72.
*The information posted above is for educational purposes only. Always check with your doctor before initiating any changes in your medical treatment. If you do not, then The Two-Minute Health Fact, Dr. Judson Somerville, nor The Optimal Dose is responsible!