Calcium supplements could raise dementia risk in women who suffer a stroke

by Rosie Taylor for The Daily Mail:

Calcium supplements could dramatically raise the risk of dementia in women who suffer a stroke, a new study found.

Thousands of women take the supplements to combat brittle bones caused by osteoporosis after the menopause.

But those who have had strokes were seven times more likely to develop dementia if they were taking calcium, scientists have found.

Those who had not had strokes but whose brains showed signs of damage – known as cerebrovascular disease – were also three times more likely to have dementia than those not taking the supplements.

There was no association between calcium supplements and dementia in women with no evidence of cerebrovascular disease.

Lead scientist Dr Silke Kern, from the University of Gothenburg in Sweden, said: ‘Osteoporosis is a common problem in the elderly. Because calcium deficiency contributes to osteoporosis, daily calcium intake of 1000 to 1200mg is recommended.

‘Getting this recommended amount through diet alone can be difficult, so calcium supplements are widely used.

‘Recently, however, the use of supplements and their effect on health has been questioned.’

She pointed out the observational study did not show dementia was triggered by calcium supplements.

For the research, published in the journal Neurology, scientists analysed 700 women aged between 70 and 92, who were all free from dementia at the start. 

Of the total, 98 were taking calcium supplements and 54 had already experienced a stroke.

The women’s memory and thinking skills were tested and their progress was followed for five years. Brain scans were also carried out on 447 of the participants.

During the course of the study, 54 more women had strokes and 59 developed dementia. 

Among the women who had CT scans, 71 per cent had lesions on their brains’ white matter, which is a marker for cerebrovascular disease.

Researchers found, overall, women who took calcium supplements were twice as likely to develop dementia as those who did not.

But when they analysed results further they realised the increased risk was limited to women who had a history of cerebrovascular disease, especially stroke.

Dr Kern stressed the study was small and more work was needed to confirm the findings.

Previous research has suggested calcium supplements affect the body differently from food and may be linked to a higher risk of artery disease.

Dr Doug Brown, of the Alzheimer’s Society charity, said: ‘While this research does not show a direct link between calcium supplements and increased dementia risk, it does warrant further investigation.

‘People should not worry about eating and drinking calcium as part of a normal, healthy balanced diet. Calcium is essential to build strong bones and teeth and also aids muscle contraction.’

He said anyone concerned about taking the supplements should see their GP.

Dr David Reynolds, from Alzheimer’s Research UK, said: ‘The finding warrants further exploration, but due to the observational nature of this study and the small number of women involved, it is difficult to draw strong conclusions about the reasons behind the link.’

He pointed out healthy adults needed around 700mg of calcium a day which could be easily obtained from dairy products such as milk and cheese, and green leafy vegetables.

‘The majority of people should not need calcium supplements,’ he added.

Source: http://dailym.ai/2bnl3qW