You Wanted to Know: Calcium


Today I want to talk about one of the body’s most important (and one of my favorite) minerals: Calcium.  Calcium is the most abundant mineral in the body, and serves many crucial functions, including building and maintaining strong bones and teeth, making muscles and nerves work, clotting blood and keeping your heart beating regularly. Without calcium, we wouldn’t be able to live. One of our viewers, Jade, asked me about this important mineral on Twitter


Even though calcium is very important, you don’t need to have your calcium levels checked regularly unless your doctor is concerned that your calcium might be too high or too low (though sometimes routine blood work will happen to include calcium numbers). Sometimes, people may have calcium values that are slightly high or low without experiencing any bad effects, which is why calcium values may not be particularly useful in isolation, without any other tests or symptoms.

Conditions that may cause calcium levels to be too high include being on bed rest, taking too many calcium or vitamin D supplements, hyperparathyroidism, hyperthyroidism, certain types of cancer and sarcoidosis. Certain medications like lithium, tamoxifen and thiazide diuretics can also raise calcium levels above normal. The most common cause of low calcium values is vitamin D deficiency (which is one reason why I recommend everyone get 15 minutes of sunlight a day or take a 1000 IU vitamin D supplement daily). Hypoparathyroidism, kidney failure, liver disease, malabsorption, pancreatitis and osteomalacia can also cause low calcium levels.

However, often when people talk about measuring calcium values, they’re actually concerned about osteoporosis, which is a disease that causes bones to become thin, weak and prone to fractures. Osteoporosis can have multiple causes and be genetic – but long-term, low calcium levels are one thing that can lead to it. According to the International Osteoporosis Foundation, this dangerous health condition causes millions of fractures every year and someone has an osteoporotic fracture every three seconds. One in three women over 50 will have an osteoporotic fracture in her lifetime, compared to one in five men.

However, not everyone with osteoporosis will have abnormal calcium levels, so measuring blood calcium isn’t the best way to diagnose this condition. Instead, the USPSTF recommends that all women aged 65 or older, or younger women with increased fracture risk, be screened for osteoporosis using a DEXA scan. DEXA scans use low-dose x-rays to look at your lower spine and hip, or sometimes your wrists, fingers, leg or heel and provide an estimate of your bone density. Currently there is not enough evidence to recommend routine DEXA scans for men.

Getting enough calcium in your diet is one important way to keep your bones strong and healthy. Dairy, including cheese, milk and yogurt, is a rich source of calcium, but you can also get calcium from foods like broccoli, collards, kale, mustard greens, bok choy, salmon, sardines, almonds, sunflower seeds, and fortified juices, cereals and breads. You can learn more about non-dairy sources of calcium here.

Calcium and vitamin D supplements may also help, and you can take 600 mg of calcium with 400 mg of magnesium daily (magnesium may help prevent calcium’s potentially constipating effects). However, always talk to your doctor before starting a new supplement, especially because calcium supplements may not be right for everyone.

To learn more about this vital mineral, take a look at this calcium fact sheet.