“How much calcium should I be taking?”
It’s a question I get several times a day from women of all ages, but mostly from those in the menopausal and peri-menopausal age group.
The answer I almost always give is – less than you think.
And for most women, probably none.
It’s not that I don’t think calcium is important
It is. Adequate calcium and vitamin D are critically important in building and maintaining a healthy bone mass.
But most women, with the exception of those who can’t tolerate dairy, are already getting a significant amount of calcium intake in their diet. So much so that taking calcium supplements adds little to their overall health.
In fact, the US Preventive Services Task Force recently recommended against routine calcium and vitamin D supplementation in healthy post menopausal women.
What harm can a little extra calcium do me?
More than you might think. Calcium supplementation can lead to –
- Kidney stones Too much calcium can lead to kidney stones, a risk confirmed by the Women’s Health Initiative Calcium Study. In this study, women were given 1000mg a day of calcium plus 400 IU of vitamin D (regardless of vitamin or dietary intake) or a placebo. Not surprisingly, there was a significant reduction in fractures in women over 70 who took their calcium as prescribed, but at the price of a 17% increase in kidney stones. For every 10,000 women taking calcium, there were two less hip fractures but 5 extra cases of kidney stones.
- Constipation. Calcium can also cause constipation, so why take more than you need? (If constipation is a problem for you, try taking calcium with magnesium).
- Interference with absorption of both iron and zinc.
You may also have heard that calcium supplementation can lead to heart disease. It’s still an open question. Some studies suggest up to a 20% increase in heart disease in men and women who take calcium supplementation. Other studies do not find this risk, or find it only in men and not women. In the Women’s Health Initiative study cited above, no increase in coronary calcium scores were seen in women who took 1000 mg of calcium daily, which is a reassuring result.
Calcium and other vitamins and mineral pills are called “Supplements” for a reason
They are meant to supplement, not replace, the primary source of calcium intake, which is food.
So instead of taking supplements, get your calcium in your diet.
What About Vitamin D?
Its a question without a good answer. The USPSTF recommendations only applies to Vitamin D doses under 400 IU. We don’t know if higher doses of D are worthwhile or not, although the WHI study suggested they are beneficial when taken with calcium in preventing fractures in post menopausal women.
My Recommendation
Unless you’re at increased risk for fracture (You can calculate your fracture risk here), forgo the supplements and get your calcium from dietary sources.
If you don’t eat dairy, look to non-dairy calcium sources, and only take as much calcium supplementation as you need to make up the difference between dietary sources and the RDA for your age group.
I’m not adverse to vitamin D supplementation, but I recommend doses of 800IU daily.
Chart from NIH Dietary Fact Sheet on Calcium
Additional Reading
- NIH Dietary Supplement Fact Sheet on Calcium
- National Osteoporosis Foundation – Calcium and Vitamin D: WHat You Need to Know
- NY Times Well Blog – Thinking Twice About Calcium Supplements
- Calcium Confusion from the WHI – TBTAM
A slightly different version of this post originally appeared on Web MD.
