Vitamin D and calcium supplements: call for consistent dosage recommendations
There is a need for clear international consensus on how much calcium and vitamin D is suitable for older women to take when looking to improve their bone health.
A study published in Menopause looked at 163 women between 57 years and 90 years whose vitamin D levels were too low. They were given calcium citrate tablets to meet their recommended intake of 1,200mg per day, as well as doses of vitamin D ranging from 400 to 4,800 international units daily.
The experts found that about 9% of the women then developed excess levels of calcium in their blood and 31% developed excess levels in their urine, even though they were taking normal doses of the supplements.
Excess blood and urine calcium levels can lead to kidney stones and other problems.
Women should have their blood and urine calcium levels measured before they start using supplements and again within three months. Those whose levels are high before they start receiving supplements are more likely to develop excess levels after supplementation.
“Vitamin D is needed for the body to absorb and process calcium,” says a spokeswoman for Arthritis Research UK. “Although there are national and international guidelines on levels of vitamin D supplementation to maintain healthy bones, currently there is no universal consensus on how much should be consumed in our diet.
“Our researchers are currently looking at the impact of three different doses of vitamin D supplementation on bone health, which we expect will reveal what is the most effective dose and how often it should be given.”