Millions of Americans over the age of 30 suffer from a condition called osteopenia – but what exactly is it?

Osteopenia, a precursor to osteoporosis, means that a person’s bone mineral density (BMD) is lower than normal, but not low enough to be considered osteoporosis.

Both men and women can develop osteopenia. Risk factors for the condition include having a family history of osteoporosis, being petite, smoking, drinking alcohol, and having a diet low in calcium.

To prevent low BMD, the National Institutes of Health recommends an intake of at least 1,000 milligrams of calcium per day.

Remember, calcium sources aren’t only limited to dairy-based foods like milk, yogurt and cheese. Here are some other foods that are surprisingly high in calcium:

-Canned salmon

-Broccoli

-Spinach

-White beans

-Oranges

-Strawberries

“Also, adding weight-bearing exercises to your routine will build strong bones,” said Dr. Cynara Coomer, chief of breast surgery and director of the Comprehensive Breast Center at Staten Island University Hospital and Fox News Medical A Team member.