Maintaining Balance: Calcium’s Role and the Nutrients That Help it Work
Most women know that calcium is needed for healthy, strong bones, but many don’t realize its important role in homeostasis, the body’s ability to maintain internal balance. Calcium, the most abundant mineral in the human body plays a central role in regulating blood pH, and maintaining proper function of nerves, muscles and even your heart. In order to do its job effectively it must find balance.
That balance comes from the orchestrated direction of several other elements in order to maintain a tightly controlled blood pH between 7.35 and 7.45 . Cofactors and minerals like phosphorus, magnesium, vitamin D, vitamin K2, sodium and potassium help ensure that calcium is absorbed, utilized, and stored properly. This orchestration becomes vital to postmenopausal women due to the hormonal shifts that can affect bone metabolism.
Calcium Where it’s Needed
Bones act as buffers for blood calcium. This enables the body to resist any rapid changes in pH levels. If the pH level in blood decreases and becomes too acidic, your parathyroid gland releases a hormone (PTH) to stimulate osteoclasts, cells that break down bone. This process releases calcium from the tissue into the bloodstream to rebalance the pH. If there’s an insufficient amount of vitamin D in your body this process may fail and lead to poor calcium mobilization and weak bones. (more on vitamin D below)
The opposite happens when pH rises and becomes too alkaline. When there’s too much calcium, the body sends calcium from the blood into other cells or excretes it in your urine. If this is left untreated, calcium deposits (calcification) accumulate in tissues like kidneys, joints and arteries. Excess calcium has been shown to increase the risk of kidney and cardiovascular disease, pain and digestive problems. Many women over 50 consume enough calcium in their diet, yet the necessary cofactors are not in balance. This results in calcium not getting to where it’s needed and winding up where it’s not wanted.
What’s Needed for Balance
Phosphorus along with calcium make up the mineral content of bone called hydroxyapatite. Phosphorus is the acidic partner to calcium’s alkaline element. Together they work to buffer the blood and maintain a strong skeletal structure. A common problem occurs when excess phosphorus is present due to a diet heavy in processed foods and sodas. This inturn impedes calcium absorption.
Magnesium works synergistically with calcium. It helps convert vitamin D into its active form calcitriol helping to enhance calcium absorption. Magnesium helps to keep calcium in the blood and prevent it from depositing into soft tissues. Unfortunately in older women, magnesium is often deficient. This is a key risk factor for osteoporosis, arrythmias, and muscle cramps. Without proper amounts of magnesium, the cells, often muscle and nerve cells, can become overstimulated by calcium resulting in spasms. If you are loading your body with green leafy vegetables, nuts, seeds, grains and all the other wonderful magnesium abundant foods but still falling short, you should consider supplementing. There are many forms of magnesium which I will not cover in the scope of this article but stay tuned for an upcoming article devoted to all its amazing roles in the body.
Vitamin D is essential for calcium absorption in the intestines. Without it, less than 15% of dietary calcium is absorbed. Since our bodies have trouble synthesizing vitamin D from sun as we get older, supplementing with D3, the active and most absorbable form, may be necessary.
Vitamin K2, an unsung hero in bone health, plays a critical role in directing calcium toward bones and teeth and keeping it from arteries and organs. It activates proteins like Osteocalcin to help bind calcium to bone and the equally important Matrix Gla protein that helps in preventing calcium deposits in arteries. It’s been shown that even if bone density is normal, if you’re lacking in K2 you are at greater risk of arterial calcification.
Potassium and Sodium are electrolytes that affect calcium balance. Too much sodium can contribute to bone loss, while conversely, a potassium rich diet, which is abundant in fruits and vegetables, reduces calcium loss and can improve bone health. A balance of the two is good practice.
Getting it Right
If possible, one should always take a food first approach when thinking about calcium. If not guided, supplementation could lead to a damaging imbalance. So check in with your health practitioner before choosing supplements.
In summary, calcium is essential but doesn’t ever work alone. Absorbing and utilizing calcium requires an orchestra of elements performing their best to assure it’s shuttled where it needs to be. Nutrient deficiencies in magnesium, vit D, vit K2 and potassium or too much of things like phosphorus and sodium from processed foods and drinks can keep calcium from doing it’s job effectively. Getting the balance right will not only be helping your bones but your heart, kidneys and overall health.
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