Both vegetarian diets and hip fractures are becoming more common with women. In the U.S., about five percent of the population practices meat-free eating. Unfortunately, it might not be the right dietary choice for women who need to protect their bones, according to a recent study.
Diet Affects Hip Health
Hip fractures are the most common type of fracture in older women, and these injuries have a huge impact on long-term health and quality of life. Recognizing this fact, researchers from the School of Food Science and Nutrition at University of Leeds in the U.K. compared the risk of hip fracture in women during a specific age span. The women were divided into groups based on their diets. The groups included vegetarians (vegans were combined with vegetarians due to the small number of participants), occasional meat-eaters, regular meat-eaters and women who did not eat meat, but did eat fish (pescatarians). The only diet associated with a higher risk of hip fracture was the vegetarian diet. The results of the study are published in BMC Medicine.
The study included more than 26,000 women living in the U.K. between ages 35 and 69. Their diet groups were based on a 217-item food frequency questionnaire that the women began between 1995 and 1998. Women who ate meat five or more times per week were in the regular meat-eater group. Women who ate meat less than five times per week were placed in the occasional meat-eater group. Using hospital records, the researchers identified 822 hip fractures over about 20 years in these women. Hip fractures occurred in three percent of the women.
The key finding of the study was that after adjusting for other hip fracture risks such as smoking and age, women on a vegetarian diet had a 33 percent higher risk of hip fracture than women who were regular meat eaters. None of the other diets had any association with an increased or decreased risk of hip fracture.
Why Become a Vegetarian?
Many people switch to a vegetarian diet because they believe it to be healthier than an omnivorous plan. And several studies support this view—people on vegetarian diets show a reduced risk of chronic diseases such as diabetes, heart disease and cancer. Another benefit is environmental. Vegetarians produce a lower carbon footprint that will hopefully reduce global warming.
Why Strictly Plant Based Might Hurt Our Bones
In the U.K, about six percent of the population follows a vegetarian diet. Although healthier in some ways, studies also show that a diet without animal protein from fish or meat is associated with lower bone mineral density. This may result in weaker bones that can break easily. Loss of mineral density may be due to a lack of proteins and nutrients such as calcium, vitamin D, vitamin B12 and omega-3 fatty acids that are more abundant in animal products than in plants.
Another factor that may contribute to fractures in vegetarians is body mass index (BMI). BMI is a measure of body fat based on height and weight. Vegetarians tend to have a lower BMI than meat eaters and low BMI has been associated with a higher risk for hip fractures. A nutrient that may also be deficient in vegetarian diets and add to the risk of hip fracture is insulin-like growth factor (IGF-1).
The research team concludes that vegetarians are at a higher risk for hip fracture than regular meat eaters. This does not mean that they encourage women to abandon vegetarian diets. They call for further research to confirm their findings and to find out if vegetarian diets in men also increase hip fractures. They would like to see further research into the role of BMI and how specific nutrients in animal-based foods that reduce fracture risks could be replaced in a vegetarian diet. These studies could lead to effective interventions to reduce hip fractures in people on vegetarian diets.