Every cell in your bones, heart, and brain needs a steady supply of calcium to work properly. Calcium supplements can help with osteoporosis, heartburn, PMS, and more. However, their use in higher doses comes with certain health risks such as kidney stones. Read on to learn the benefits and risks of supplementing.
Calcium is the most abundant mineral in the human body and accounts for about 1-2% of body weight. Each and every cell – in the bones, heart, muscles, and nervous system – need it to work.
Calcium plays essential roles in muscle contractions, blood coagulation, bone and teeth formation, and much more [ 1 ].
Only around 1% of total body calcium is found in the blood; the remaining 99% is stored in the bones and teeth [ 2 , 3 ]. Proponents
Strengthens bones & prevents osteoporosis
May help prevent colon cancer
Helps maintain normal blood pressure
May prevent pregnancy complications
Reduces PMS symptoms
Intake needs to be balanced with other nutrients
Possibly unsafe in excess amounts
May increase the risk of kidney stones
May increase the risk of prostate cancer
May cause stomach upset
Reduces iron absorption when taken with meals
The best food sources of calcium are dairy products: milk, yogurt, and cheese [ 4 , 5 , 6 ]. Canned or fresh fish with bones (sardines, sardelles, or even salmon)
Tofu (calcium-set is best)
Leafy greens (kale, broccoli, sprouts, bok choy, collard greens)
Nuts (hazelnuts, walnuts, almonds)
A healthy and balanced diet should provide most people with all the calcium they need. But some people require more, while others are unable to get enough of this mineral from food. In such cases, supplemental calcium may be a good solution.
As we’ll outline, the balanced intake of calcium along with other nutrients is key to getting the desired benefits while minimizing the risk of side effects.
Antacids made of calcium carbonate are effective and FDA-approved for treating mild indigestion and heartburn [ 12 , 13 ].
Intravenous calcium gluconate can reverse heart rhythm issues induced by high potassium blood levels (hyperkalemia); it’s an FDA-approved, first-line treatment [ 14 ].Oral calcium supplements are effective for treating and preventing low calcium blood levels (hypocalcemia). Intravenous calcium salts are needed for severe hypocalcemia with muscle spasms [ 15 ].The buildup of phosphate is a major issue in some patients with kidney failure. Oral calcium carbonate or calcium acetate is effective as a phosphate binder. Calcium acetate (PhosLo) may be a better option, and it’s FDA-approved for this condition [ 16 ].Calcium and vitamin D are two crucial nutrients for the prevention and treatment of osteoporosis. The National Osteoporosis Foundation (NOF) recommends calcium intake of 1000 mg/day for men aged 50-70 and 1200 mg/day for women aged 51+. Individuals who can’t meet their needs from food sources are advised to take supplements [ 17 ].Adequate calcium intake from foods and supplements can help prevent osteoporosis in young people and specific types such as glucocorticoid-induced osteoporosis. That said, the evidence for calcium benefits in men is much weaker and requires further investigation [ 18 , 19 , 20 ].Although calcium supplements are effective individually, most experts suggest combining them with vitamin D, which enhances calcium absorption and instructs the body to use it for bone formation [ 17 , 21 ]. Premenstrual syndrome (PMS) is extremely common and the exact causes are diverse. Low levels of vitamin D and calcium can trigger PMS or contribute to the symptoms, according to a large review of 28 trials [ 22 ].According to multiple studies with women suffering from PMS, calcium can relieve many of the symptoms such as anxiety , depression , fatigue, and water retention [ 23 , 24 , 25 , 26 ].Some evidence suggests calcium can improve bone health in physically active people, including athletes, military personnel, and manual workers.During intense exercise , blood pH levels drop as lactate levels rise. To compensate, the body releases calcium from bones, which increases bone loss if the demand for calcium isn’t met. Calcium supplements might be helpful during these periods of intense strain on the whole body and skeletal system [ 27 , 28 , 29 ].In one trial with 243 army personnel, calcium and vitamin D improved bone density (BMD) and strength [ 30 ].In yet another trial, 32 well-trained female athletes were given a meal with ~1,350 mg calcium 90 minutes before strenuous exercise . Calcium reduced the typical bone loss seen with prolonged high-intensity exercise [ 27 ]. Healthy People In another study with 867 healthy men, calcium with vitamin D also improved BMD, especially in the neck, hips, and spine. However, a large review concluded that more evidence is needed before we can claim that supplementation is beneficial for all non-deficient, healthy, older men [ 31 ].In sum, calcium supplements strengthen the bones in people at risk of deficiency. They might also protect the bones of vigorously-active healthy people and athletes.According to several review studies, calcium supplements use is associated with lower colon cancer rates and relapse. Most of the trials found that calcium supplements were more effective when taken with vitamin D at the same time [ 32 , 33 , 34 , 35 ].Calcium supplements may aid in colon cancer prevention by protecting colon cells from the damaging effects of free bile acids. Another way calcium might work is by activating a pathway called APC /beta-catenin, which becomes underactive early in colon cancer. Vitamin D, in turn, helps break down bile acids and enhances DNA repair [ 36 , 37 ]. That said, the studies don’t prove the actual anticancer effects of calcium supplements. They’re not meant to treat any kind of cancer. Getting sufficient amounts of calcium from food or supplements and keeping vitamin D levels in check might help prevent colon cancer.Adequate calcium intake might prevent the onset of high blood pressure, according to a large review of over 3,000 people. Calcium intake (via food or supplements) slightly reduced blood pressure, […]