A record number of people are turning to plant-based diets to take advantage of the many health benefits they offer, but it may come at the expense of their bones, a new study has found.
What exactly did the researchers find? Middle-aged women who never eat meat are more likely to break a hip than women who regularly consume meat and/or fish.
Further study is needed to understand why vegetarians appear to be at higher risk for hip fractures, but researchers suspect that low body mass index (BMI) and nutrient deficiencies play a role.
“While a lower BMI is beneficial for many health conditions, being underweight can lead to low fat mass and poor bone and muscle health, which can each increase the risk of hip fracture,” said said study author James Webster. He is a doctoral researcher at the School of Food Science and Nutrition at the University of Leeds in England. BMI is an estimate of body fat based on weight and height. The average BMI of vegetarians in the study was slightly lower than that of meat eaters.
“People with less body fat have less cushioning during falls, and falls account for 90% of hip fractures,” he explained.
Meat and fish are also great sources of several bone-healthy nutrients, including protein, vitamin B12, and vitamin D.
“It is possible to get most of these nutrients from plant sources, eggs and dairy products, [but] previous studies have found lower intakes of these nutrients in vegetarians,” Webster said. In the study, vegetarians had lower protein intakes and vitamin B12 than people who ate meat five or more times a week.
In the study, researchers looked at hip fracture rates in more than 26,000 women aged 35 to 69 who ate no meat more than four times a week (occasional meat eaters); the pescatarians who ate fish but no meat; vegetarians; and regular meat eaters who ate meat at least five times a week. The women completed food frequency questionnaires, and these were compared to hospital records to see who had suffered a hip fracture. During approximately 20 years of follow-up, there were 822 hip fractures.
Vegetarians were the only group with a high risk of hip fracture after researchers controlled for other factors known to increase this risk, including smoking and level of physical activity.
The results were published online Thursday in the journal BMC Medicine.
There are steps vegetarians can take to better protect their bones while enjoying the heart and other health benefits of a plant-based diet, Webster said. It starts with maintaining a healthy weight, which increases the likelihood of healthy bones and muscles and helps reduce the risk of hip fracture.
Eating plenty of fruits and vegetables, nuts, legumes, beans and whole grains provides most of the nutrients needed for bone health and fracture prevention, he added.
Consider Fortified foods and supplements too, he suggested. “Eating foods fortified with essential nutrients or taking nutritional supplements can also help to avoid nutritional deficiencies, especially of vitamin B12 and omega-3 fatty acids, which are difficult to obtain directly from plant foods. “, Webster said.
Avoiding smoking and excessive alcohol consumption, while exercising regularly, can also help keep bones strong. “Resistance exercises, where you lift or pull against resistance, such as weight training, can be particularly beneficial in increasing bone and muscle strength,” Webster said.
New Austrian research published last week confirms this advice: vegans who lift weights or do strength training have stronger bones than vegans who only do other forms of exercise, such as cycling or swimming.
Dietitians not involved in the new study pointed out that building strong, healthy bones involves more than just getting enough calcium.
Magnesium, potassium, boron, zinc, copper, manganese, vitamin D and vitamin K2 are also important, said New York registered dietitian Robin Foroutan.
“Protein is critically important for building a strong and flexible bone matrix,” she said. “Vegetarian sources of protein may be more difficult for some people to digest and absorb, making the protein less bioavailable.”
Focusing on high-quality vegetarian protein sources, as well as dark leafy greens, nuts, seeds and other mineral-rich plant foods, can support bone health, Foroutan said.
Lona Sandon, director of the clinical nutrition program at the School of Health Professions at the University of Texas Southwestern Medical Center at Dallas, agrees.
His advice to vegetarians? “Aim for lots of quality protein from eggs and dairy sources if they’re willing to include it in their diet,” Sandon says. Alternatively, increase your intake of beans, legumes, nuts, nut butters, and seeds to ensure adequate amounts of all bone-building nutrients beyond calcium.
Marion Nestle, a retired professor of nutrition, food studies and public health at New York University, warned that more research is needed before drawing conclusions about fracture risk in vegetarians.
“Vegetarians who do not eat red meat but eat other animal products should not be at higher risk of bone fractures,” she said, but underweight veganshowever, may lack essential nutrients.
Learn more about how to eat a healthy vegetarian diet at the Academy of Nutrition and Dietetics.
Copyright © 2022 Health Day. All rights reserved.