Calcium and vitamin D help children develop strong bones. In older adults, they help protect from osteoporosis and bone breaks. ((Rob Carr/Associated Press))

Most Canadian and U.S. girls could use more calcium, but that's not necessarily true for other age groups, a new report says.

The report by the Institute of Medicine was commissioned by the U.S. and Canadian governments to study and then recommend daily intake levels for calcium and vitamin D.

"National surveys in both the United States and Canada indicate that most people receive enough calcium, with the exception of girls ages nine to 18, who often do not take in enough calcium," Tuesday's report reads.

"In contrast, post-menopausal women taking supplements may be getting too much calcium, thereby increasing their risk for kidney stones."

The new recommendations for calcium are:

  • Ages one through three: 500 milligrams of calcium per day.
  • Ages four to eight: 800 mg/day.
  • Adolescents: 1,300 mg/day.
  • Women ages 19 through 50 and men up to age 71: 800 mg/day.
  • Women over 50 and both men and women age 71 and older: 1,000 mg/day.

If supplements are needed to ensure adequate calcium intake for bone health, the panel suggested lower-dose supplements.

"We could not find solid evidence that consuming more of either nutrient would protect the public from chronic diseases ranging from cancer to diabetes to immune function," said committee chair Catherine Ross, who is also a professor of nutritional science at Penn State University, University Park.

Together, calcium and vitamin D help children develop strong, healthy bones. In older adults, they help protect from osteoporosis, bone fractures and breaks, says the American Society for Bone and Mineral Research.

"A diet that includes the right amounts of calcium and vitamin D is the simplest first step in promoting good bone health," said Dr. Sundeep Khosla, the society's president and an endocrinologist at the Mayo Clinic in Rochester, Minn.

"These new guidelines will help clarify recent misperceptions about the benefits and risks of insufficient or excessive intake," Khosla added in a statement.

A one-cup serving of most dairy products contains 200 to 300 milligrams of calcium.

Foods rich in calcium include dairy products such as milk, cheese and yogurt, fortified soy beverages, tofu, salmon, almonds and broccoli.