Your Body Won't Absorb Calcium -- What Can You Do?

Calcium is essential for the health of your bones and plays important roles in nerve transmission and muscle function. On average, humans only absorb about 30 percent of the calcium in foods, according to the Office of Dietary Supplements. This percentage can vary depending on the types of foods you eat and other lifestyle habits. If your body does not absorb calcium properly, several steps can be taken.

Vitamin D

Vitamin D is an essential factor in the proper absorption of calcium. Vitamin D allows calcium to pass from your gut into your bloodstream so that your body has access to the mineral. Without proper amounts of vitamin D, your body cannot absorb calcium, regardless of how much you consume.

You can increase the amount of vitamin D in your body by increasing your intake of vitamin D-rich foods, such as salmon, mackerel, sardines, fortified milk, egg yolks, enriched cereals and fortified orange juice. You can also increase the amount of vitamin D in your body by exposing yourself to the sun for short periods a couple days per week. Your body is able to synthesize some vitamin D with the help of ultraviolet rays.

Timing

Consuming too much calcium at one time can actually negatively affect your body's ability to absorb the mineral. Your body absorbs calcium more efficiently when it is consumed in small amounts throughout the course of the day, rather than in large doses. According to the Office of Dietary Supplements, calcium absorption is highest when calcium is consumed in doses of less than 500 mg at a time.

Diet

Your body excretes some of its calcium through your urine, stool and sweat. Some minerals, such as sodium, increase the amount of calcium that your body excretes, according to the Office of Dietary Supplements. High protein intake can also increase the rate at which your body excretes calcium. To increase your body's absorption of calcium, reduce the amount of sodium and protein in your diet.

Some plant foods can also decrease the amount of calcium your body is able to absorb. These plant foods, which include spinach, sweet potatoes, beans and collard greens, contain substances called phytic acid and oxalic acid, which bind to calcium and inhibit its absorption. To increase your body's ability to absorb calcium, eat calcium-rich foods separately from these plant foods.

Alcohol

Drinking too much alcohol can inhibit your body's ability to absorb calcium in two ways. Alcohol decreases the amount of calcium that your gut is able to absorb, decreasing the amount of calcium in your blood. Alcohol also inhibits enzymes that are necessary to convert vitamin D into its active form. If the vitamin D in your body is not in its active form, it cannot increase the absorption of calcium. If you are not able to absorb calcium, reduce your intake of alcohol or eliminate it from your diet completely.