While we hear a great deal about the importance of milk and other calcium-containing foods for bone health, a new study shows fruits and vegetables also are important in the prevention of osteoporosis.

The study, which was reported in The American Journal of Clinical Nutrition, evaluated participants from the Farmington Heart Study and found lifelong dietary intakes of potassium, magnesium, fruit and vegetables were determinants of bone mineral density in elderly men and women.

Fruits and vegetables are important because they play a role in neutralizing the acid created during the normal digestive process — a process that usually draws minerals out of the bone, thereby reducing its strength, according to Dr. Douglas Kiel, assistant professor of medicine at Harvard Medical School and associate director of medical research at Hebrew Rehabilitation Center for Aged.

"Fruits and vegetables help to prevent this loss of bone mineral density because they create a more alkaline environment in the body — they neutralize the acid without depending on the buffering effects of the bone mineral," Kiel explained. "It also is possible that potassium and magnesium have direct effects on bone cells."

People who consume a lot of highly processed foods often lack adequate amounts of potassium and magnesium. Good sources of potassium include fruits and vegetables such as bananas, oranges, tomatoes, potatoes, broccoli and melon. Good sources of magnesium, meanwhile, include a variety of foods including fruits and vegetables, milk, fish and whole grains.