Sydney: Scientists have discovered that chocolate may increase the likelihood of osteoporosis and bone fractures in women.

In a new study published in the American Journal of Clinical Nutrition women who ate chocolate every day were found to have less dense bones than those who ate it less than once a week. according to scientists at the University of Western Australia.

Chocolate containing high levels of flavanols has recently been found to have beneficial health effects, particularly on the cardivascular system. But most chocolates do not contain high levels of this substance and manufacturers rarely label their products with health information.

In the Australian study, scientists monitored the amount of chocolate eaten over several weeks by 1,001 women aged 70 to 85. They then measured the bone density and strength of each woman using X-rays. The researchers found the women who ate chocolate less than once a week had significantly stronger bones than those who consumed the treat on a daily basis. Low bone density was found in the hips, neck, tibia and heel bones of the women surveyed.

The researchers believe the findings may be because chocolate contains oxalate, which can reduce calcium absorption, and sugar, which is linked to calcium excretion. Calcium is vital for maintaining healthy bones.