For years, experts have warned vegetarians and vegans that their diets may put them at risk for developing osteoporosis. This is because these groups tend to consume insufficient amounts of protein and calcium, supplements believed to promote bone health.

But an April 2009 study, published online in Osteoporosis International, found that the bone density of vegans and their meat-eating counterparts are not as different as once thought. In fact, they are identical.

Researchers from Australia and Vietnam compared the bone health of 105 post-menopausal vegan Buddhist nuns to that of 105 non-vegetarian women. The researchers chose to study Buddhist nuns because of their life-long devotion to vegan diets. Because many vegetarians still consume dairy, the study excluded them to protect the integrity of the results.

Since vegans eat only plant-based foods, getting enough nutrients can be challenging. In fact, the Buddhist nuns had very low calcium intakes—averaging only about 370 mg a day compared to the recommended daily intake of 1,000 mg. Plus, their protein intake was nearly half that of the non-vegetarian group.

However, the findings showed that the vegan nuns had the same bone mineral density as the non-vegetarians. This means that despite the vegans' low calcium and protein intake, they were no more at risk for osteoporosis than those who did take in enough nutrients.

The researchers believe the results are great news for vegans and vegetarians who are worried about their risk for osteoporosis. However, it's important to understand that many other factors impact the probability of developing osteoporosis—these include exercise, smoking habits, and even soda consumption. Overall, your calcium and protein intake isn't a be-all and end-all of whether you'll develop osteoporosis.

Though the findings didn't turn the researchers into proponents of the vegan lifestyle, they said that fruits and vegetables likely have a part in any bone-healthy diet.

Learn More About Diet's Impact on Osteoporosis:

• Food and Osteoporosis: Learn about foods that may stunt healthy bone growth
• Osteoporosis: Vitamin D and K
• Nutritional Supplements to Help Build Bone and Prevent Osteoporosis