Calcium supplements may slow bone loss in postmenopausal women

Hot flushes, poor sleep, dry mucous membranes and joint pain are some of the most common symptoms many women experience when they reach the menopause. However, the period following the menopause can also bring long-term symptoms and increased risk of diseases. One of the most widespread is osteoporosis, and after menopause, the risk increases significantly. In Denmark, one in three women has osteoporosis, and the risk increases with age. Most people have the condition without realising it.

This problem was precisely what Inge Tetens was interested in investigating further. She is a professor at the Department of Nutrition, Exercise and Sports at the University of Copenhagen and primarily researches the interaction between nutrition and ageing.

Inge Tetens led this new study that examined whether a daily calcium supplement affects bone health in postmenopausal women.

And after just one year, the trial showed clear results:

“Women who had taken calcium supplements maintained their bone mineral density, whilst it declined in the placebo group. This suggests that calcium supplements may be a simple tool for supporting bone health – and thus, in the long term, preventing osteoporosis – after the menopause,” says the professor.

How they did it

The study involved a total of 417 apparently healthy postmenopausal women with an average age of 56 years. The participants were randomly assigned to four different groups. Three groups received different types of calcium supplements providing 800 mg per day divided into two doses, while the fourth group received a placebo-supplement.

All participants also received a daily vitamin D supplement, which is important for calcium absorption. In addition, the women were encouraged to continue their usual lifestyle.

After 12 months, the participants' bone mineral density was measured in the spine and the femoral neck.

The results showed that bone mineral density was maintained in the groups that had taken calcium supplements, while it decreased by approximately 1% in the placebo group. In other words, the trial demonstrated that calcium supplementation helped counteract the bone loss that is normally seen after menopause.

 “The results suggest that a calcium supplement of 800 mg a day, taken in two doses, may be an effective nutritional strategy for supporting bone health in postmenopausal women who are also getting sufficient vitamin D,” says Inge Tetens, adding:

“It is somewhat surprising that the results show such clear effects, because most of the women already had a sufficient average daily intake of calcium from their diet,” says the professor.

It is somewhat surprising that the results show such clear effects, because most of the women already had a sufficient average daily intake of calcium from their diet

But couldn't women simply consume more dairy products instead?

“Yes, but then you would have to drink a great deal of milk. That amounts to almost 0.7 liters of milk – on top of your existing daily intake, mind you. And very few people actually do that,” explains Inge Tetens.

Should be included in future recommendations

The study tested various types of calcium supplements in combination with vitamin D, but there was no evidence to suggest that the type of supplement had any effect on the women’s final bone mineral density.

According to Inge Tetens, the key point of the study is that it concerns a target group with a specific need. A need which, as the study shows, is greater than previously assumed.

And this is worth bearing in mind when looking at the official recommendations for dietary supplements, the researcher believes.

Currently, the Danish Health Authority recommends taking vitamin D and calcium from the age of 70. There are therefore no official recommendations specifically regarding calcium supplements for apparently healthy women from the age of 50. But for this particular age group, it should be a consideration, says the professor:

“As our study shows that a daily calcium supplement can have a clear effect on bone health, I believe there is good reason for our findings to be taken into account the next time the Danish Health Authority updates its recommendations for women in the postmenopausal period,” concludes Inge Tetens.