The number of vegans in Western societies is on the rise. It is estimated that between 2 - 6% of Americans are vegan. And up to 10% of Americans consider themselves vegetarian. But these diets have additional challenges.
It can be hard to get enough vitamin B12, iron, zinc, iodine, and omega 3-fatty acids on a plant-based diet. A new study even suggests that dietary deficiencies may put those on a plant-based diet at higher risk of bone fractures.
More than 50,000 people participated in the study, but the majority of the participants were meat-eaters, with almost 30,000 participants.
The study found that after controlling for other factors, non-meat eaters had a higher rate of bone fractures.
Tammy Tong, the researcher who led the study, said in a statement:
"This is the first comprehensive study on the risks of both total and site-specific fractures in people of different diet groups. We found that vegans had a higher risk of total fractures which resulted in close to 20 more cases per 1000 people over a 10-year period compared to people who ate meat. The biggest differences were for hip fractures, where the risk in vegans was 2.3 times higher than in people who ate meat, equivalent to 15 more cases per 1000 people over 10 years."
Previous studies have found people who eat diets low in protein and calcium have poorer bone health and low Body Mass Index (BMI). Although it is hard to say for certain that diet is the culprit, it is suggestive.
A factor that needs to be further studied is how calcium is absorbed by the body. Various factors, such as the presence of Vitamin D change how much calcium our bodies absorb.
Tong explained:
"Well-balanced and predominantly plant-based diets can result in improved nutrient levels and have been linked to lower risks of diseases including heart disease and diabetes. Individuals should take into account the benefits and risks of their diet, and ensure that they have adequate levels of calcium and protein and also maintain a healthy BMI, that is, neither under nor overweight."
More research is needed before we can say that there is a causal link between diet and fractures. This study primarily included European people, which is not representative of the population as a whole.
There were also only 2,000 vegans in the study, which is not enough to make any definitive conclusions. But the study had many strengths, such as the length of the study, so the findings cannot be dismissed. If you are on a plant-based diet and are concerned, it might be a good idea to meet with a dietitian to make sure you are getting everything you need out of your meals.
h/t: IFL Science, BMC Medicine
