THOUSANDS OF Irish women taking calcium tablets to slow osteoporosis are doubling their risk of having a heart attack, according to a new research study.
The supplements are neither safe nor effective and so should be “taken with caution”, according to the research published this morning in the online issue of the journal Heart.
The results will prove a shock to women who take the tablets, particularly as they come highly recommended as a way to reduce the bone loss caused by osteoporosis.
The large-scale study of 24,000 participants in Germany showed the opposite, however. The bone-related protective effect was modest, only about 10 per cent, yet the health risk showed itself to be enormous, according to the research findings.
Women taking a combination of vitamins and mineral supplements including calcium were 86 per cent more likely to have a heart attack than women not using any supplements.
The situation was worse for women taking calcium supplements alone, who were more than twice as likely to have a heart attack, the study found.
The news was mixed for those boosting calcium levels by eating calcium-rich foods.
Previous studies had suggested that high dietary intake could help lower the risk of a range of conditions including heart attack, stroke, obesity and type two diabetes.
The study said there was little or no evidence to show that this was true. Yet elevating calcium levels through diet alone did not cause the increased health risks linked to the supplements.
“This study suggests that increasing calcium intake from diet might not confer significant cardiovascular benefits, while calcium supplements, which might raise [heart attack] risk, should be taken with caution,” the authors write.
The difference could be in the way the calcium was absorbed, they say.
Dietary calcium intake was spread out through the day, while supplements caused a sharp spike in calcium levels at the time the supplements were taken.
“It is now becoming clear that taking this micronutrient in one or two daily [doses] is not natural, in that it does not reproduce the same metabolic effects as calcium in food,” the authors write. Their use should therefore be discouraged.
The participants were part of the “Heidelberg” study, an ongoing tracking of the group’s longer-term health outcomes related to cancer and nutrition.
CHILDHOOD OBESITY CAESAREAN LINK
BABIES DELIVERED by Caesarean section are twice as likely to become obese in childhood than those born vaginally, a US study published today has found.
When measured aged three, 15.7 per cent of children born by Caesarean section were obese compared with 7.5 per cent of children born vaginally, the study led by Harvard researchers found.
The research followed 1,255 children delivered in eight Boston hospitals between 1999 and 2002. Mothers who delivered by section tended to weigh moreand their babies tended to have higher birth weight. However, the odds held at double after adjusting for the maternal body mass index and the birth weight of the baby.
The study does not give reasons why children born by section are more likely to be obese. However, researchers speculate that the difference in gut bacteria acquired at birth may be a factor.
