Does Chocolate Inhibit The Ability To Absorb Calcium?

Calcium is an essential nutrient, and you require fairly large amounts of this mineral in your diet to maintain optimal health. Your body contains about 3 lb. of calcium, almost all of which is sequestered in your bones and teeth. If you do not consume enough calcium, or if the calcium in your diet is poorly absorbed, you can become calcium deficient. Calcium absorption is affected by a variety of factors, including the types of foods you eat. Chocolate contains chemicals that could decrease calcium absorption.

Long-Term Impacts

The impacts of inadequate calcium absorption are not always immediately obvious. According to the Linus Pauling Institute at Oregon State University, calcium levels in the fluids bathing your cells and tissues must be tightly regulated to keep them within what's known as the physiological range. Your body possesses mechanisms to withdraw calcium from your bones if dietary calcium intake is insufficient for your needs. Therefore, any dietary pattern that chronically interferes with calcium absorption could contribute to loss of bone strength and eventually osteoporosis.

Absorption

Intestinal calcium absorption is enhanced by vitamin D, physical activity, increased stomach acid and at least some dietary protein and fat. Conversely, calcium absorption is inhibited by low stomach acid, lack of exercise and vitamin D deficiency. Excessive fat, protein or phosphorus intake can interfere with calcium absorption and increase calcium loss in your bowel movements or urine. In addition, certain chemicals – phytates in whole grains and oxalates in tea, dark leafy greens and chocolate – could bind calcium in your intestine and impair its absorption.

Role Played by Calcium Sources

While oxalates from some foods significantly inhibit calcium absorption, those from other foods may not exert the same profound effects. Furthermore, the calcium source itself plays a role in the efficiency of calcium absorption. For example, a study published in the October 1989 issue of “The American Journal of Clinical Nutrition" showed that spinach, which is relatively high in calcium, is nevertheless a poor source of absorbable calcium due to its high oxalate content. In contrast, the calcium from milk is relatively well absorbed even when it is consumed with oxalate-containing foods.

Significance

Chocolate's interference with calcium absorption probably presents more of a theoretical than a real concern, particularly since chocolate usually represents a minor part of the diet. Oxalates from some foods, such as spinach and other dark leafy greens, certainly interfere with calcium absorption; and avoidance of all oxalate-containing foods is sometimes recommended for people suffering from medical problems such as kidney stones. To be on the safe side, if you are on a calcium supplement, don't take it within two hours of eating chocolate or any other oxalate-containing food.