Sticking to a vegetarian diet was linked to a higher risk of hip fracture in women, a cohort study has found.
Vegetarian women aged 35-69 saw a 33% higher risk of hip fracture than those who regularly ate meat (HR 1.33, 95% CI 1.03-1.71) for longer of 2 decades of follow-up, James Webster, PhD, of the University of Leeds in the UK, and colleagues reported in BMC Medicine.
This risk of hip fracture was not observed in pescatarians (HR 0.97, 95% CI 0.75-1.26) or in women who ate meat only occasionally (HR 1 .00, 95% CI 0.85-1.18).
Low intake of protein, calcium and other micronutrients linked to bone and muscle health are often of concern with vegetarian diets, Webster said in a statement. “So it’s especially important to continue research to better understand the factors behind the increased risk in vegetarians, whether it’s particular nutrient deficiencies or weight management, so that we can help people to make healthy choices.”
He added that this study does not warn people to avoid vegetarian diets altogether, but to weigh the pros and cons of any diet with personal circumstances. Additionally, women need to know exactly what nutrients they may need to supplement for proper nutrition.
“Vegetarian diets can vary greatly from person to person and can be healthy or unhealthy, as can diets that include animal products,” he advised.
In the 822 cases of hip fracture seen in 26,318 women aged 35-69 in the UK Female Cohort Study, BMI did not appear to play any predictive role in this association with diet type. That being said, women with a BMI below 23.5 had a 46% higher fracture risk, regardless of diet type.
These models were adjusted for a multitude of potential confounders, including ethnicity, sociodemographics, marital status, menopausal status, number of children, history of cardiovascular disease, cancer, diabetes, and lifestyle factors such as exercise, smoking, and use of nutritional supplements.
“Hip fracture is a global health problem with high economic costs that leads to loss of independence, reduced quality of life and increased risk of other health problems,” said Janet Cade, PhD, co – author of the study, also from the University of Leeds, in a statement.
“Plant-based diets have been associated with poor bone health, but there has been a lack of evidence on links to hip fracture risk,” she said. “This study is an important step in understanding the potential risk that plant-based diets might pose in the long term and what can be done to mitigate those risks.”
The researchers found key nutritional differences between women with different diets. Not surprisingly, women who ate meat regularly had the highest protein, vitamin D, and vitamin B12 intake. On the other hand, the vegetarian group had the lowest consumption of the three.
However, total calcium intake was similar between all diets.
In general, the women in the study who followed a pescatarian or vegetarian diet tended to be younger, have a higher level of education, were more likely to have professional or managerial jobs than manual jobs, and were less likely to be married or to have children. Women who followed these diets also tended to weigh less than those who ate meat regularly.
Regular meat eaters also had some of the highest levels of cancer, diabetes and cardiovascular disease at baseline.
Diets were confirmed using a 217-item food frequency questionnaire. Women considered “regular” meat eaters were those who ate five or more servings per week, while “occasional” meat eaters ate less than five servings. Pescatarians ate fish but no meat, and vegetarians abstained from fish and meat.
Webster and his co-authors reported no disclosures.