Healthy older women should not take daily low doses of vitamin D and calcium to prevent fractures, an expert panel says. The U.S. Preventive Services Task Force issued the advice. This is an independent group that provides advice to doctors and the government on preventive care. The group reviewed 19 studies involving women who were past menopause. They were randomly divided into groups. Some women received vitamin D and calcium pills daily. Others received placebo (fake) pills. The doses given varied. The task force found no reduction in fracture risk for women taking up 400 international units of vitamin D and 1,000 milligrams of calcium daily. Past studies also have suggested a higher risk of kidney stones for women taking these pills. Some experts have recommended even higher doses for older women. But the task force said there was not enough evidence to make a judgment about larger doses. The advice does not apply to vitamin D and calcium obtained from foods. The task force report is a draft. Public comment is invited. USA Today and Reuters Health news service wrote about the task force report June 13.
By Howard LeWine, M.D.
Harvard Medical School
What Is the Doctor's Reaction?
There seem to be conflicting messages about how much vitamin D and calcium we need. Only 6 months ago, the U.S. Preventive Services Task Force concluded that vitamin D pills could reduce fracture risk in people over age 65, as long as they took in enough daily calcium.
Now the task force has a new report. It suggests that daily low-dose vitamin D pills, combined with calcium pills, do not prevent fractures in women or men with average fracture risk. The task force defines a low dose of vitamin D as 400 international units (IU) or less. The specific calcium supplement mentioned is calcium carbonate. The dose is 1,000 milligrams per day.
Actually, the prior advice and this new draft don't contradict each other. The advice from 6 months ago referred to older people with a higher than average risk of falls. Also, there were two other important differences. Compared to the new draft statement, the prior advice:
- Suggested a higher dose of vitamin D, up to 1,100 IU daily
- Did not say how a person should get enough daily calcium, whether from pills or food
The task force also issued another new draft statement. This one says there is not enough evidence to support the use of low-dose vitamin D and calcium pills to prevent cancer. The prior advice regarding higher doses of vitamin D in pills was similar. There is also no evidence to suggest that higher doses will decrease cancer risk.
What Changes Can I Make Now?
The Institute of Medicine, another independent expert group, has offered this advice on how much vitamin D you need:
- 600 IU a day for everyone ages 1 to 70
- 800 IU a day for those 71 and older
There is no proof that taking vitamin D pills will improve your health as long as you get enough vitamin D from fortified food and drinks and/or sun exposure. But many people are not sure if they are getting enough. So I personally recommend a daily pill containing 1,000 IU of vitamin D3.
Some doctors suggest that this dose is too low. The Institute of Medicine says that up to 2,000 IU of vitamin D per day is safe.
To maintain bone health and prevent fractures, you need to get enough calcium. How much you need is debated. The Institute of Medicine now recommends 1,000 to 1,200 milligrams a day. This may be too high. Other countries set the daily recommended calcium intake at less than 1,000 milligrams.
Get your calcium from your diet. At this time, calcium pills should only be used when your doctor recommends them. Recent studies suggest that high-dose calcium pills might increase the risks of heart disease and certain types of cancer. Unlike calcium in your diet, calcium in pills also can cause kidney stones.
Good dietary sources of calcium include:
- Dairy products, such as milk, yogurt and low-fat cheese
- Fish with soft bones that you eat, such as sardines or salmon
- Legumes, such as beans, peas and lentils
- Green leafy vegetables, such as broccoli, kale and cabbage
What Can I Expect Looking to the Future?
Most vitamin and mineral pills have not lived up to their hype. In fact, vitamin A and vitamin E in high doses are harmful.
Some of the bloom has come off the rose for vitamin D as well. But pills containing 2,000 IU daily or lower appear to be safe.