As long as people stick to the recommended dosages, running the risk of a heart attack is unlikely, say experts. GERALDINE LING reports
Calcium pills are safe to take, but stick with the recommended dosages, say medical and other experts.
Many people here, especially women over 40, take calcium supplements because of their concerns about osteoporosis. Some may also buy calcium supplements for their family members, including children, for
bone health, said Mr Daniel Quek, the president of Health Supplements Industry Association of Singapore (HSIAS).
So naturally, there was some cause for concern after press reports of a study published in the British Medical Journal last month. The study, by a multinational research team, said calcium supplements may increase heart attack risk by as much as 30 per cent.
Calcium pills are among the top-selling supplements sold here. Figures from the HSIAS showed that Singaporeans spent some $458 million on supplements last year.
This amount is expected to go up by over 10 per cent this year to about $510 million.
Mr Chay Zhu En, 19, who has been taking 800mg of calcium daily for the past three years, said the press reports made him rethink his decision to take the supplement.
He had started taking the pills as he read that bone mass is best built from young.
“A heart attack is not a joke,” said Mr Chay, who is waiting to do his national service.
Agreeing, Mrs Millie Chua, 57, said: “I was taken aback by the reports. What can protect bones best besides calcium?”
The housewife, who started taking about 1,000mg of calcium a day to guard against bone loss 10 years ago, has stopped popping calcium pills after reading the reports.
However, there is no need to be alarmed by the study, health professionals told Mind Your Body.
Its authors had stated that the risk of a heart attack increases only when one consumes more than 805mg of elemental calcium supplements daily, noted Dr Lau Tang Ching, the president of the Osteoporosis Society here.
Taking 800mg or less a day is unlikely to increase one’s risk of a heart attack, Dr Lau pointed out.
In fact, given that many foods – such as milk products – are high in calcium, many healthy Singaporeans may not even need calcium supplements, he said.
Those who eat the usual three meals a day are likely to meet the required daily intake of 800 to 1,000mg of calcium, if calcium-rich foods are included.
However, people with certain medical conditions will need calcium pills. For example, those with renal failure typically have to avoid protein-rich foods like milk products, which are also high in calcium.
Even then, Dr Lau said, the recommended dosage of calcium supplements is below 800mg a day, which is not associated with the increased risk of heart attacks.
Dr Stanley Chia, a consultant at the department of cardiology at the National Heart Centre Singapore, noted the study’s limitations.
He said the researchers did not have access to the subjects’ individual data for most of the trials. Instead, the diagnosis of a heart attack had depended largely on factors such as a subject’s self-diagnosis.
Associate Professor Adrian Low, a senior consultant at the cardiac department at the National University Heart Centre Singapore, added: “Misdiagnosis is quite possible. The use of calcium supplements can cause
gastrointestinal symptoms, like nausea and indigestion and these might be confused with a heart attack.”
Moreover, none of the trials had set out to show a direct link between calcium supplementation and heart disease, said Ms Lim Yen Ping, a senior pharmacist at National University Hospital.
Instead, the primary aim of most of the trials was to investigate the effect of calcium on bone density.
Some risk factors for heart disease, like family history or abdominal obesity, were not taken into account, she said.
The type of calcium pills studied are also less commonly taken by Singaporeans.
Dr Baldev Singh, a consultant cardiologist at Parkway East Hospital, said the study focused only on supplements that had only calcium, and not those with vitamin D added.
The latter is commonly found in the calcium supplements sold in Singapore. Calcium pills with added vitamin D are generally safe, heart-wise, reported a 2007 study by the United States government.
Dr Lau Kean Wah, a consultant cardiologist at Gleneagles Hospital, said: “Do make sure that there is also vitamin D in the supplements as the latter has been proven to reduce heart attacks.”
The full study is published on www.bmj.com.