Should You Take a Daily Calcium Supplement?

July 24, 2023

“Calcium is a mineral that is very important for many bodily functions, not just bone health,” says Jacob Wolf, ND, LAc, Dipl. OM, naturopathic physician at University Hospitals Connor Whole Health. “It is also crucial for muscle and nervous system function. And, because the body doesn’t produce it naturally, it is important to get a steady supply from the food we eat or with dietary supplements.”

A Balancing Act between Blood, Bone & Tissue

Most calcium is stored in the bones and the teeth to keep them strong and healthy. However, it is also important that some calcium remains in the bloodstream. Available blood calcium is used to:

Support muscle movement
Assist nerves in carrying messages from the brain to every part of the body
Maintain healthy blood pressure and circulation

The Importance of Vitamins D3 and K2

The parathyroid glands – four pea-sized organs found within the thyroid gland – help regulate how much calcium goes where and when. To do this efficiently, they require the assistance of Vitamins D3 and K2.

“Vitamin D3 facilitates the absorption of calcium from the intestines into the bloodstream. Vitamin K2 then acts as a messenger to signal the body to activate bone-building mechanisms by sending some of that calcium to the bones not body tissues,” says Dr. Wolf.

“The body tries to balance how much calcium goes to the bones and how much remains in the bloodstream to support other functions,” says Dr. Wolf. “If blood calcium levels drop too low, it can lead to symptoms such as numbness and tingling in the hands and feet, muscle spasms and heart arrhythmias. If calcium levels remain low for too long, your body will extract the calcium it needs from the bones. Unchecked, this can lead to thinning, weakened bones that are prone to fracture.”

Conversely, if blood calcium levels are too high, it can cause symptoms such as nausea, constipation, belly pain and confusion. “Excess calcium in the blood is almost always due to parathyroid disease,” says Dr. Wolf. “Patients with high blood calcium will usually be referred to an endocrinologist for further evaluation.”

Dietary Sources, Supplements or Both?

Although it’s always best to get nutrients from food sources rather than supplements, calcium and its partners D3 and K2, are often the exceptions. “Unless one’s daily diet routinely includes foods that are high in all three nutrients, supplements will be needed,” says Dr. Wolf. Examples of good food sources include:

Calcium. Low-fat dairy products like milk, cheese and yogurt are high in calcium but many people either don’t like dairy or are dairy-intolerant and have trouble digesting these foods. Still others may be vegan or vegetarian and dairy foods are not an option. Other good food sources of calcium include:

Dark leafy greens like spinach, kale and Bok choy
Broccoli
Calcium-fortified orange juice
Almonds and almond milk
Salmon and sardines
Tofu
Edamame and winter squash

Vitamin D3. The body produces Vitamin D3 naturally when exposed to sunlight; however, excessive sun exposure is not recommended for a variety of health reasons. D3 is only available in a limited number of food sources so supplementation is usually necessary. Food sources include:

Oily fish (salmon, sardines, herring and mackerel)
Red meat and liver
Egg yolks
Some fortified fatty spreads and cereals

Vitamin K2. This little-known vitamin is present in some foods like egg yolks, chicken liver and blue cheese, but not in sufficient amounts to meet the body’s needs. In addition, many of the foods that are known to be high in vitamin K2 are not heart-healthy and should be limited or avoided. Therefore, supplements are advisable for almost everyone. K2 supplements are often combined with Vitamin D and/or calcium.

Types of Calcium Supplements

Calcium supplements are available in a wide variety of formulations. The biggest difference between them is the amount of available calcium but some have other benefits or side effects as listed below:

Calcium carbonate has the most available calcium at 40 percent but is also the most constipating.
Tri-calcium phosphate also has about 40 percent calcium but is less constipating.
Calcium citrate is the most easily absorbed and may be better for those on reflux medications because it doesn’t require acid to break it down. However, it only has 20 percent available calcium so you have to take more.
Calcium gluconate and calcium lactate contain much less available calcium – 9 and 13 percent respectively.
Calcium hydroxyapatite is a newer type of calcium supplement. Unlike other supplements which are made from minerals taken from the earth, this form is made from animal sources and includes several other bone-enhancing micronutrients.

Recommended Daily Allowances (RDA)

The highest demand for calcium is during the pre-teen and adolescent years because the bones are forming and growing. Therefore, children between 9 and 18 years of age should be getting 1,300 mg. per day. The daily calcium requirements for adults are as follows:

Women age 19-50: 1,000 mg
Women 51 and up: 1,200 mg
Pregnant/lactating women: 1,000 mg
Men age 19-70: 1,000 mg
Men 71 and up: 1,200 mg

Vitamin D3: Dr. Wolf recommends 1,000-2,000 international units (IUs) per day for those who have not had their vitamin D levels tested. Higher doses may be needed for those who test as D3-deficient.

Vitamin K2: Currently, there is no established RDA.

Most vitamin supplements are now available as chewable gummies. Although not ideal because of the added sugar, if swallowing pills is an issue, gummy supplements are an acceptable alternative.

Four Ways to Keep Calcium Levels on Track

In addition to a healthy diet that includes plenty of calcium-rich foods and taking supplements, Dr. Wolf recommends the following:

See your provider for an annual physical and bloodwork, including Vitamin D. This will typically include a metabolic panel that measures the available blood calcium. If high blood calcium is detected, you will likely be referred to an endocrinologist.
Ask your doctor if a coronary artery calcium score test is appropriate for you. This noninvasive, low-dose CT scan measures the amount of calcium buildup in the walls of the coronary arteries and can predict the risk of future heart attack. University Hospitals offers this test at no-cost.
Limit dietary sodium. Salt can cause excessive calcium excretion through the kidneys.
Keep your bones strong with weight-bearing exercise. If walking is your primary mode of exercise, be sure to add extra weight for maximum benefit – your body weight alone is not sufficient. Always talk to your doctor before beginning an exercise program.