Calcium

Background: Calcium is the most abundant mineral in the body. It has many essential functions. Among other things, it is instrumental in muscle movement; it is an integral part of nerve transmission, and it plays a role in the constriction and dilation of our blood vessels and in blood clotting. Calcium is also a significant component of our bones, nails, and teeth. In fact, most of it is stored in the bones and teeth.

Many things regulate the calcium levels in our bodies. First, our body does not make calcium. We get it from the foods we eat. With the help of vitamin D, calcium is absorbed from the intestine and into the bloodstream. Most calcium is stored in the bones. When calcium levels are too low, the parathyroid gland, kidneys, and intestine work together to increase it by extracting it from the bones. The parathyroid gland is primarily responsible for this: It senses low levels of calcium and sends parathyroid hormones (PTH) to the bones, signaling the latter to release calcium into the bloodstream so it is available for other essential functions of the body.

The purpose of explaining this complex mechanism is primarily to illustrate the numerous problems in the body that can contribute to calcium problems and where these problems can manifest: our heart and lungs, nervous system, blood pressure, muscles, bones, blood clotting and others. Again, the body is an incredibly well-oiled machine and works hard to balance this out carefully.

What Does Calcium Do for the Body?

Respiratory: Calcium is essential for lung function – for the production of mucus and for constriction of bronchial tubes (especially necessary for airway defense when foreign substances enter the lungs).

Cardiovascular: Calcium is also essential for proper heart muscle functioning (contraction and relaxation) and may help lower blood pressure. There is an ongoing debate on whether calcium supplementation in older people causes an increased risk for heart attacks. This is one of those “risk versus benefits” questions. Excess calcium in diabetics, for example, may increase the risk of heart attack and stroke. For those with osteoporosis, taking calcium (in the absence of diabetes) may be worth the risk to avoid possible fractures. If you are unsure which road to take, discuss it with your healthcare provider.

Gastrointestinal: Supports digestion (enzymes that help break down foods)

Genitourinary: Normal calcium levels help the kidneys function optimally. Possibly reduces premenstrual syndrome (PMS) symptoms.

Musculoskeletal: Calcium is necessary for the production and maintenance of bones; it is also essential for optimal muscle growth and function – especially contraction and relaxation).

Neurologic: Calcium is critical for nerve transmission throughout the body.

Skin: Calcium lends to better skin, shedding old skin cells and laying down new ones. It maintains a protective barrier to help defend the body from elements, the environment, and bacteria. Calcium is also instrumental in wound healing.

Mental Health: Since calcium plays an essential role in nerve transmission, it has a huge role in brain function. It also plays a substantial role in the production of neurotransmitters like serotonin (which is largely responsible for mood) and in hormone synthesis like melatonin, an integral hormone for sleep, among other things. Adequate amounts of calcium in the body, may play a role in decreasing depression and helping with stress and anxiety.

Glucose: May help decrease blood sugar (especially if taken with vitamin D)

Cholesterol: May help lower cholesterol

Immunity: Calcium plays a vital role in activating the immune system. Maintaining normal levels may help various autoimmune diseases.

Cancer: Possibly protects against colorectal and prostate cancers

Other: Calcium promotes blood coagulation and clotting.

Calcium regulates so many things in our bodies that too little or too much can cause many problems. So, it is vital to maintain normal levels in the body.

Causes of Too Little Calcium (Hypocalcemia)

Some of the factors that can contribute to lower calcium levels include vitamin D disorders, parathyroid dysfunction, low levels of albumen in the blood (due to malnutrition, liver and kidney problems, thyroid issues, parathyroid dysfunction, infection, kidney issues, medications, dietary intake, too much salt, caffeine, alcoholism, malabsorption (gastrointestinal diseases, surgeries), genetics, pancreatitis, aging, low magnesium, high phosphorous, and others.

Symptoms of Hypocalcemia

• Muscle disturbances: spasms, aches, and/or cramps

• Numbness or tingling of the extremities.

• Insomnia

• Fatigue

• Dizziness

• Brain fog

• Mood changes: Possibly some depression or anxiety

• Eczema or psoriasis breakouts

• Cataracts

• Loss of hair

• Dry skin

• Dental changes

• Osteopenia/osteoporosis - weak bones. Degenerative bone changes: "hunchback"

• Chronic joint and muscle pain

Causes of Too Much Calcium (Hypercalcemia)

Parathyroid or thyroid problems, too much calcium intake, too much vitamin D, dehydration, immobilization, some cancers (breast, lung, kidney, ovarian, squamous cell, and others), some medications (i.e. lithium, thiazide diuretics), genetics, kidney disease

Symptoms of Hypercalcemia

• Kidney stones

• Excessive thirst

• Frequent urination, decreased urination.

• Nausea/vomiting

• Stomach upset/pain

• Gas/bloating

• Constipation

• Muscle weakness

• Bone/joint pain

• Mental changes: confusion, fatigue, depression

• Palpitations, irregular heartbeat

• Syncope

• Edema/limb swelling.

• Weight gain

• Decreased appetite.

• Metallic taste

• Weakness

• Macular degeneration

• Colon polyps

• Kidney stones

• Possibly causes greater predisposition to prostate cancer and heart attack

Cautions/Contraindications: Parathyroid gland disorder, decreased kidney function, kidney stones, and sarcoidosis. Use caution with certain medications: thyroid medications, most osteoporosis medications, antacids, laxatives, seizure medications, certain antibiotics: “cyclins” (like doxycycline and tetracyclines, minocycline), fluoroquinolones, ciprofloxacin, and others. In many cases, the medicines need to be spaced apart during the day. Read labels or speak to a healthcare professional if you have any questions.

Forms:  There are two primary forms of calcium used to supplement the diet: Calcium carbonate and calcium citrate. Calcium carbonate is obtained from rocks and shells. Calcium citrate is often synthesized in a lab by combining citric acid (an organic product) and calcium carbonate or calcium hydroxide. 

Which one to choose? They each have their advantages and disadvantages:

• Calcium carbonate contains relatively more calcium, so it is typically a better value but should be taken with meals to increase stomach acid, which increases absorption in the gut. Calcium carbonate helps for heartburn and stomach acid (i.e. TUMS).

• Calcium citrate is better absorbed than calcium carbonate but has less relative calcium content. This may be the better form for older people because they tend to produce less stomach acid: Calcium carbonate will not be absorbed as readily.

Dosages: As directed

Recent (2024) NIH recommendations:

Daily doses:

14-18 years 1,300 mg 1,300 mg

19-50 years 1,000 mg 1,000 mg

51-70 years 1,000 mg 1,200 mg

71+ years 1,200 mg 1,200 mg

The ideal way to get calcium is through the diet. The following are calcium-rich foods:

• Green leafy vegetables - like spinach, broccoli, kale, collard greens, okra, rhubarb

• Cheeses - almost all cheeses are good - especially hard cheeses (30 gm) (Cheddar, Parmesan, Greyure); soft cheeses (60 gm) (brie, camembert - with a warning that it has a strong smell!), feta (6o gm) and mozzarella (60 gm); cream cheese (30 gm)

• Milk (200 ml) - whole, skimmed.

• Yogurt (natural)

• Sardines, fatty fish like herring, black cod, salmon, sardines, bluefin tuna, anchovies, herring, mackerel, black cod, salmon, sardines, bluefin tuna, trout, swordfish, whitefish, striped bass, whitefish, striped bass, mackerel, mussels

• White beans

• Tofu

The above are some of the better calcium-rich foods. You may want to familiarize yourself with these even if you do NOT have a known calcium-related problem!

Notes:

• Moderation is the key.

• There are numerous calcium supplements out there. Be careful, as some products have been found to contain contaminants like lead, cadmium, and arsenic.

• In most cases, this is best taken with vitamin D, which helps the body absorb calcium.