Q&A: Be careful with your supplement regimen

So should you or shouldn't you take calcium and vitamin D supplements? Some recent developments may have left consumers confused.

The U.S. Preventive Services Task Force said Tuesday that healthy postmenopausal women should not take daily low doses of vitamin D and calcium to prevent bone fractures because they slightly increase risk for kidney stones. In its draft recommendation, the panel also said existing research is insufficient to assess the risks or benefits of taking vitamin D to prevent cancer.

A recent study found calcium supplements may raise some people's risk for heart attacks.

Yet for years, experts have touted both calcium and vitamin D as key nutrients for bone health.

The Institute of Medicine, which provides independent advice, recommends 600-800 international units (IU) of vitamin D daily and 700-1,300 milligrams of calcium, depending on your age.

Many foods are rich in calcium and fortified with vitamin D. Sunlight triggers production of vitamin D in the skin and is a major source.

But nutrition experts say many people still may need to fine-tune their diets to get enough.

Endocrinologist Bess Dawson-Hughes, director of the Bone Metabolism Laboratory at the USDA's Human Nutrition Research Center on Aging at Tufts University in Boston, answers questions about the new recommendations.

How much calcium?

Here are the current recommendations
for calcium intake based on age group,
in milligrams per day:

Children ages 1-3: 700

Children 4-8: 1,000

Adolescents 9-18: 1,300

All adults 19-50: 1,000

Men 51-70: 1,000

Women 51+: 1,200

Men 71+: 1,200

To get this amount of calcium in food, children and adults would need to consume at least three servings a day of calcium-rich foods such as low-fat milk, yogurt or fortified orange juice. Teens need four servings. A cup of milk has about 300 milligrams of calcium.

Source: Institute of Medicine,
USA TODAY research

Q: Why are calcium and vitamin D so critical?

A: They are both essential for the development and maintenance of healthy bones. Older people with adequate vitamin D levels have fewer falls than those with lower D levels. The U.S. Preventive Services Task Force said that.

Low levels of vitamin D have been associated with a range of chronic diseases, such as diabetes, hypertension, heart disease, some cancers, infections and autoimmune problems. These early findings warrant further investigation.

The National Institutes of Health is currently funding some very large trials to define the effects of vitamin D on the burden of many of these chronic diseases.

Q: Can people get enough vitamin D and calcium in their diets, or do they need to take supplements to meet the recommendations?

A: Many adults are not getting quite enough calcium in their diets. They have two choices. My first recommendation is to modify their food intake to include one more calcium-rich food a day. We have lots of foods to choose from, and calcium has been added to many foods, including orange juice and cereal.

If you can't get it through foods, then use supplements to bring your intake up to the 1,000 to 1,200 milligrams a day, the amount recommended for adults.

You need to get up into the recommended intake level of calcium, but there is no point in exceeding that level because there is no benefit. And there are potential risks, however low they might be, that there would be adverse consequences to exceeding those levels. So why spend more money and take more risks?

Vitamin D is more complicated, because we get it from sun exposure and from food. It's not easy to get 600 to 800 IU of vitamin D daily from food sources. You'd have to be eating a lot of wild salmon, and you'd have to do it every day. � If you're not getting any sun contribution, you are going to need a supplement.

Q: Is there is an increased risk of heart attack from taking calcium supplements?

A: I don't think we have a conclusive answer to that yet. There is certainly enough of a suggestion that high-dose calcium supplements may be detrimental. I recommend avoiding high-dose calcium supplement use, such as exceeding the institute recommendations for calcium by 500 to 1,000 milligrams a day.

People should use calcium supplements only as necessary to reach the institute requirements.

Q: If postmenopausal women are taking vitamin D and calcium supplements to prevent osteoporosis, do you think they should stop, based on this panel's advice?

A: You should estimate how much calcium and vitamin D you are getting through food, and if you are below the Institute of Medicine requirement, you should increase it with food if you can. If you can't, then you should take a supplement that fills in the gap.

Q: Any other advice?

A: We need to encourage food sources of calcium, vitamin D and all other nutrients. It's an old message, but it's timely again because we are getting a backlash on supplements.

New Poll: The Supreme Court and the Health Care Law

More than two-thirds of Americans hope the Supreme Court will overturn some or all of the 2010 health care law, according to a new poll conducted by The New York Times and CBS News. Just 24 percent said they hoped the court “would keep the entire health care law in place.”

The Supreme Court is expected to decide a challenge to the law by the end of this month.

Forty-one percent of those surveyed said the court should strike down the entire law, and another 27 percent said the justices should overturn only the individual mandate, which requires most Americans to obtain health insurance or pay a penalty.

These numbers have not changed much in recent months and appeared to be largely unaffected by the more than six hours of arguments in the Supreme Court in March.

There was greater Republican opposition to the law than Democratic support. About two-thirds of Republicans in the recent survey said the entire law should be overturned, while 43 percent of Democrats said all of the law should be upheld.

More than 70 percent of independent voters said they wanted to see some or all of the law struck down, with a majority saying they hoped to see the whole law overturned. Twenty-two percent of independents said they hoped the entire law would survive.

Responses varied by education, too. Nearly a third of respondents with a college education said they would like to see the law upheld, compared with about 20 percent of those without a college degree.

Legal scholars and political scientists are divided over whether the justices take account of public opinion in making their decisions.

In a 2010 study published in The Georgetown Law Journal, Lawrence Baum of Ohio State University and Neal Devins of the College of William & Mary concluded that the justices were not much concerned with mass opinion.

�Supreme Court justices care more about the views of academics, journalists and other elites than they do about public opinion,� they wrote. �This is true of nearly all justices and is especially true of swing justices, who often cast the critical votes in the court�s most visible decisions.�

The nationwide poll is based on telephone interviews conducted May 31 through June 3 on land-lines and cellphones with 976 adults, and has a margin of sampling error of plus or minus three percentage points.