Are Older Women Receiving Too Much Calcium?

CalciumThe June issue of Menopause, a peer reviewed medical journal, carried an original research article by Margery Gass, MD and colleagues which indicated that older women are taking too much Vitamin D and Calcium. She conducted a randomized and placebo controlled trial of 163 women with low Vitamin D levels. The age range of the study group was 57 to 90. They were given Vitamin D and Calcium citrate tablets to reach the recommended daily amount of 400 to 4800 IU per day of Vitamin D and 1200 mg of calcium per day. Follow-up lab studies revealed that almost 10% of the women developed elevated blood calcium levels. More disturbing was the fact that 31% developed elevated levels of calcium in their urine predisposing them to kidney stones.

The lead author suggested that every patient calculate how much calcium they are getting daily in their normal diet before supplementing it with extra calcium. Her group pointed out the benefits of clinicians periodically measuring patients 24 hour urine calcium level. Those with a level > 132 mg were at much higher risk of developing hypercalcemia and its complications and need to reduce their supplemental calcium intake. We will begin suggesting 24 hour urine collection in our patients in the near future.

The Calcium – Vitamin D Supplementation Picture Gets More Confusing

As a geriatrician who believes strongly in prevention, my perspective is that the recent high volume of research on healthy aging, chronic disease and its association with Vitamin D and Calcium supplementation has done nothing but confuse the picture for us all. I have always been an advocate of healthy eating – a balanced diet that is prepared in a manner that retains and promotes the absorption of the foods nutrients. Also, I have supported the recommendations of blue ribbon panels to supplement the diets of women of child bearing age, peri-menopausal women and post menopausal women with 1200- 1500 mg of calcium per day in addition to dietary calcium to promote healthy bones.

I have read extensively about the lower measured values of Vitamin D in men and women who are ill and have many different types of acute and chronic diseases. I have not truly accepted the idea that raising their measured serum level of Vitamin D with pill supplements did anything to improve the disease state even if we did raise the measured serum Vitamin D level. I have been amazed by experts in Europe and Asia and in the World Health Organization setting a normal lower value of measured Vitamin D level at 20 while in the USA it is 28.  I am not convinced that healthy adults with healthy kidneys cannot get adequate Vitamin D levels by 10 minutes of sun exposure a few times per week in increments which will not dramatically increase the risk of lethal skin cancers.

This was made all the more confusing by the United States Preventive Services Task Force suggesting  that Vitamin D supplements reduce the risk for older people prone to falls and this month announcing that “there is no value for postmenopausal women using supplements up to 400 IU of Vitamin D and 1000 mg of calcium daily.”  This latest ruling was based on data which showed that at 400 IU of Vitamin D and 1000 mg of Calcium daily there was no effect on the incidence of osteoporotic fractures.

Much of the data used to reach this conclusion came from the Women’s Health Initiative Studies of more than 36,000 postmenopausal women.  The USPTF noted that at this dose of Vitamin D and Calcium there was a clear increase in kidney stones which they considered a harmful effect.  At the same time as this data was being discussed, the impartial Institute of Medicine (IOM) presented suggestions and data that Vitamin D at 600 IU daily plus 1200 mg of calcium per day prevented fractures in postmenopausal women.

For my postmenopausal patients I will continue to suggest they supplement their diets with 1200 mg of calcium per day as per the IOM suggestions unless they are prone to kidney stones. They will need to stay well hydrated while I ask them to take a daily 30 minute walk exposing their arms and legs to the sun for at least 10 minutes to allow their healthy kidneys to manufacture Vitamin D.