Women with high calcium intake are at a greater risk of cardiovascular disease, a new study has claimed.

Researchers from Uppsala University in Sweden studied 61,443 Swedish women (born between 1914 and 1948) for an average of 19 years to test an association between high calcium intake and risk of ischemic heart disease and stroke.
Data were taken from the Swedish Cause of Death Registry and data on diet were taken from the Swedish Mammography Cohort.

Total calcium intake included supplemental calcium. The average intake in the lowest quartile was 572 mg per day (the equivalent of five slices of cheese) and in the highest 2137 mg per day.

Results showed that during 19 years of follow-up, 11,944 women (17 per cent) died: 3,862 of these (32 per cent) died from cardiovascular disease, 1932 (16 per cent) heart disease and 1100 (8 per cent) from stroke.

Highest rates of all-cause, cardiovascular and heart disease were observed among those with a dietary calcium intake higher than 1400 mg per day, journal bmj.Com reported.

In addition, researchers observed higher death rates among women with an intake below 600 mg per day.

Women who had a higher dietary intake of calcium exceeding 1400 mg per day and also used supplements had a higher death rate compared to those not taking supplements.

Women with a high dietary calcium intake (more than 1400 mg per day) were more than twice as likely to die compared with women with a 600 to 999 mg per day calcium intake.

The researchers suggested that diets very low or very high in calcium can override normal homeostatic control causing changes in blood levels of calcium.

The researchers concluded that high calcium is associated with "higher all-cause and cardiovascular mortality rates" and so to prevent fractures in the elderly emphasis should be placed on individuals with a low intake of calcium rather than increasing the intake of those already consuming satisfactory amounts.