Calcium from food better than pills

Jun 27 2007

The majority of women today are aware that calcium is essential in preventing osteoporosis, especially after the menopause.

Osteoporosis is a disease which causes progressive bone loss and fractures and it affects millions of Americans.

A preliminary study has found that when it comes to maintaining strong bones after the menopause, women may be better off eating plenty of calcium-rich food rather than relying on supplements for their intake of the mineral.

The researchers at Washington University School of Medicine say though their study is not definitive, dietary calcium may be better at protecting bone health than calcium which comes mainly from tablets.

They say this proved to be true even though the supplement-takers had higher average levels of calcium.

The study's lead author, Dr. Reina Armamento-Villareal says calcium from dietary sources is generally better absorbed than that from supplements, which could help explain the difference.

Dr. Armamento-Villareal, a bone specialist and assistant professor in the School of Medicine's division of bone and mineral diseases, says those getting calcium from foods also had more estrogen in their bodies which is needed to maintain bone mineral density.

As yet the food-estrogen connection remains unclear but the research says Armamento-Villareal is preliminary and offers a hypothesis to test.

For the research 183 postmenopausal women were asked to carefully log their diet and their calcium supplement intake for seven days; their bone mineral density and their urine for levels of estrogen were then tested.

The women were then split into three groups: those who got at least 70 percent of their daily calcium from supplements, those who got the same amount from dairy products and other food, and those whose calcium-source percentages fell somewhere in between.

It was found that although the "diet group" took in the least calcium, an average of 830 milligrams per day they had higher bone density in their spines and hip bones than women in the "supplement group", who consumed 1,030 milligrams per day.

Women in the "diet plus supplement group" tended to have the highest bone mineral density as well as the highest calcium intake at 1,620 milligrams per day.

An analysis showed that women in the "diet group" and the "diet plus supplement group" had higher levels of estrogen, needed for bone mineral density.

Other experts agree that the study is not definitive and suggest that those who got calcium from their diet might have also taken in more vitamin D from milk, which would aid in calcium absorption.

They say the estrogen connection might be explained by the possibility that plants were eaten which contain more of the hormone.

Dairy foods and calcium-fortified orange juice are excellent sources of calcium along with dark green, leafy vegetables but it is not as readily absorbed as calcium from dairy.

The study is published in the American Journal of Clinical Nutrition.