It’s the most abundant mineral in the body. And 99 percent of the calcium in our bodies is stored in our bones and teeth. The other 1 percent is pretty darn important as well. According to the National Institutes of Health Office of Dietary Supplements, our muscles (including the heart) depend on calcium to function. Nerve signals and hormones also rely on a small yet steady supply of calcium.
How much calcium do we need to maintain bones, teeth and other critical body functions? Babies and toddlers need 200 to 700 milligrams (mg) per day, depending on their age. From the age of four our daily need for this essential mineral varies between 1000 and 1300 milligrams.
What does that look like in food? One cup of milk, yogurt or calcium-fortified soy milk supplies about 300 mg of calcium. One ounce of cheese or 4 ounces of calcium-fortified tofu or orange juice contain about 200 mg of calcium. Vegetables such as kale, broccoli and turnip greens contain smaller amounts of calcium although calcium in these foods is generally less available to be absorbed by the body.
How do we figure calcium content from a food label? Until the newest Nutrition Facts label appears on products, just add a zero behind calcium’s Daily Value. For example, a daily value of 30 percent would mean the food contains about 300 mg of calcium.
What about calcium supplements? Concerns surfaced a few years ago that calcium supplements may be linked to an increased risk for heart attacks. This led to further investigations and revised recommendations, most notably from experts in osteoporosis and cardiology. Authorities now advise us not to exceed the upper tolerable limit (UL) for calcium – 2000 IU’s per day for adults 51 years and older and 2500 IU’s daily for 19-50 year olds. And remember that includes the total daily calcium we consume from food and supplements combined.
Calcium carbonate and calcium citrate are two common forms of supplemental calcium. Calcium carbonate relies on stomach acids to be absorbed so best to take it with meals when digestive juices are churning. Calcium citrate is more expensive but does not rely on stomach acids to be absorbed; it’s preferred for anyone with digestive issues.
Calcium’s helpmate for absorption into the body is vitamin D. Healthy people between the ages of 1 and 70 need 600 International Units (IU) of vitamin D per day. The need for vitamin D goes up to 800 IU’s daily for those over the age of 70 since our skin is less able to convert vitamin D from sunlight as we age.
Vitamin D occurs naturally in very few foods. Best sources include fish and fish oils (the same types of foods that supply omega-3 fats). Most of the milk sold in the US is fortified with 100 IU’s of vitamin D per cup. Supplemental vitamin D is often necessary when food intake and sun exposure fail to provide adequate amount of this important nutrient.