The Calcium Paradox

It’s known that our bones require calcium, however, precaution is recommended when supplementing calcium. Calcium supplements are perhaps the most confusing since there are conflicting opinions about how much calcium is needed on a daily basis to support bone integrity. But what cannot be argued is how calcium is absorbed. The American Academy of Orthopedic Surgeons states, “Not all the calcium consumed — whether through food or supplement — is actually absorbed in the intestines.”

AAOS also points to research suggesting that when calcium is taken in doses less than 500 mg, it is absorbed most efficiently. Therefore, splitting a high dose into multiple doses throughout the day would allow for greater absorption of calcium. In addition to dosage, absorption is determined by the presence of other vitamins. Some research shows that when vitamins A, D, and K are combined, calcium is utilized more efficiently in the body. The AAOS encourages patients to speak with a doctor or specialist before taking a calcium supplement. While the combination of ADK has not been recommended for supporting bone and cardiovascular health, doctors who are recommending calcium supplements may want to consider the new research on calcium absorption and ADK supplements.

Research shows that the combination of vitamins A, D, and K2 may support bone integrity and rebuilding. Vitamin K2 is required for the activation of osteocalcin—a vitamin K dependent protein that transports calcium from the blood to form a healthy bone matrix.

Vitamin K2 has been tested in several clinical trials to examine its effect on bone mineral density, which reduces the risk of fracture. In one study titled, ‘Vitamin K and the prevention of fractures: systematic review and meta-analysis of randomized controlled trials,’ researchers found that adult participants taking oral vitamin K for at least 6 months saw a reduction in bone loss as well as a reduction in bone fractures.  However, a similar study was conducted using vitamin K1, finding no increase in bone mineral density. This implies that vitamin K2 may have a more positive effect on bone mineral density than vitamin K1.

As mentioned previously, vitamin K2 can only be found in animal meat or vitamin supplements. But it’s important to note that when vitamin K2 is lacking or not utilized properly in the body, bone structure and function can be compromised. Vitamin K2 not only supports the deposition of calcium into bone; it also has a regulatory effect on vitamins A and D with regard to osteoclast and osteoblast activity.

This is partly why vitamins A and D are now being used with vitamin K in bone health supplements. Furthermore, some studies indicate that consuming high levels of vitamin A per day may cause reduced bone mineral density and increased risk of fracture. Therefore, experts recommend taking vitamins A in conjunction with vitamin K for its regulatory properties.

Vitamin D3 is also needed for proper bone growth and bone remodeling by osteoblasts and osteoclasts. Without sufficient Vitamin D, bones can become thin, brittle, or misshapen. Research shows that K2 partners with Vitamin D3 to inhibit the production of osteoclast cells (cells that break down bone) in order to help bone-building osteoblasts catch up to maintain a healthy balance.

Bone remodeling is a natural way the body removes old or weakened bone tissue in order to make room for new, stronger tissue. This process is critical to fracture repair and retaining bone density. Vitamin A also plays a role in stimulating osteoblasts (bone building cells) to secrete proteins that are required for bone mineralization, including the K2 dependent protein called osteocalcin. Combined, vitamins A and D support osteocalcin output and the regulation of osteoclasts (bone breakdown cells) and osteoblasts (bone building cells).

In terms of heart health, vitamin K2 plays an important role, especially in reducing the risk of unabsorbed calcium collecting in coronary arteries. While both vitamin K1 and vitamin K2 have been found to be absorbed well in the body, one study indicated that MK-7 (vitamin K2) has a longer half-life and is therefore utilized for a longer duration. Furthermore, another study found that postmenopausal women receiving a steady dose of MK-7 over 3 years saw improved bone strength and reduced risk of vertebral height loss in the lower thoracic region.

Vitamin K2 works primarily outside of the liver in bones and blood vessels. In blood vessels, vitamin K2 helps to maintain arterial elasticity. Vitamin D3 also supports cardiovascular function and blood pressure within normal ranges. It impacts heart health by supporting the body’s natural cytokine production and vascular function.

In her book, Dr. Rheaume-Bleue explains this synergistic relationship in one, simple statement: “Vitamins A and D collaborate to prop up vitamin K2, and we fully benefit from vitamins A and D only when we have K2 to complete the act and achieve optimal health.” She also points out another distinguishing trait shared by both vitamin A and vitamin D. Like vitamin K2, they can only be obtained from animal products, despite what health experts have been telling consumers for years.

DaVinci Laboratories of Vermont

Sheila is adamant that one should supplement calcium properly or not at all. It is critical that the calcium be transported to bones and teeth, it just needs a co-factor to do so. If not properly delivered, calcium will migrate to other areas of the body and cause unwanted effects, these areas tend to be joints (arthritis), kidneys (stones), arteries (blood clots, CV disease), and brain (dementia, cognitive impairment). At dancingbones we offer DaVinci Labs’ beautifully formulated ADK supplement and consider it fundamental for bones and health in general.


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