Calcium is a mineral that occurs naturally in your body and has many important functions. Most of the calcium in your body is stored in your teeth and bones to help them stay strong. A very small amount of calcium is in your blood, muscles, and in the fluid between your cells. This calcium helps your blood vessels expand and contract, keeps messages flowing through the nervous system, and helps the body make the hormones and enzymes it needs.
Calcium Functions
Many foods are naturally rich in calcium including dairy products such as milk and cheese along with green, leafy vegetables. If you do not eat enough calcium-rich foods to supply your body with all the calcium it needs, you body may start to pull calcium out of your bones, leaving them weak. This can put you at higher risk for broken bones or for osteoporosis.
How much calcium you need in your diet is determined by your age and by your sex. As children grow, they need more calcium to produce strong bones. Calcium needs level off during adult years, then increase as we become seniors. Women typically need more calcium as adults and seniors than men because their bones tend to be lighter and thinner which makes them lose bone mass more quickly if they do not have enough calcium. Women also lose bone quickly after reaching menopause.
Calcium Sources
Food is the best source of calcium for the body. If your doctor determines that you are low on calcium, you can try to eat more dairy products and green vegetables to boost your body’s calcium. Adding powdered milk to many foods can add a boost of calcium without affecting the flavor of the food.
If you cannot get enough calcium in food, calcium supplements can add the extra calcium you are missing. The amount of calcium you need to add in a supplement depends on how much calcium you are eating. Your doctor can tell you what your daily intake of calcium should be. Make a good estimate of how much calcium you eat every day and subtract it from your total daily requirement. The remainder is the amount of supplement you need to take each day.
Natural calcium is found in combination with other substances. These combinations are known as compounds. Common calcium compounds found in supplements include calcium carbonate, calcium citrate, calcium lactate, and calcium phosphate. The different calcium compounds digest differently, so it is important to read the label to determine when you should take your supplement and whether you should take it on an empty stomach or with food. For example, calcium carbonate generally needs to be taken with food. Calcium citrate can often be taken on an empty stomach, but tends to be more expensive.
You will often see calcium sold in combination with vitamin D. This is because the body needs vitamin D to process the calcium. Whether you need vitamin D in your supplement depends on how much vitamin D you have already in your diet. Calcium supplements come in different doses. Be sure to check the label to see how many tablets you need to take each day to reach your desired dose.
While it is important to get enough calcium in your diet, too much calcium can also cause some health problems. Taking in an excess of calcium can make it harder for your body to absorb iron and zinc. It can also cause constipation and may increase your chances of getting kidney stones.
Calcium Cautions
• If you have a food allergy to shellfish, be careful when purchasing calcium supplements. Some calcium comes from crushed oyster shells which can cause a shellfish reaction in people who are allergic.
• Calcium supplements can interact with other medications including the antibiotic Tetracycline.
• Calcium supplements should not be taken at the same time of day as iron supplements.
• If you take proton pump inhibitors to block stomach acid, consider supplements made from calcium citrate rather than other types of calcium. Calcium citrate is more easily absorbed without stomach acid.
Sources:
National Osteoporosis Foundation
National Institutes of Health: Medline Plus
National Institutes of Health Office of Dietary Supplements