Plant Based Diets and Bone Health

It’s a popular belief that dairy products are the answer if you want healthy bones. Well let’s see what the research tells us about vegan, vegetarian and omnivorous diets and bone health.

The Bone Health of Vegans and Vegetarians

Vegan and vegetarian diets are associated with factors that are thought not to support bone health, such as low body mass and low intakes of protein; yet, these diets are alkaline, a factor that favours bone mineral density.

Several recent studies have looked at plant-based diets and markers of bone health, using measures such as bone turnover, bone mineral density and fracture rates. Most of the studies do not show differences in bone health between vegetarians, vegans and omnivores as long as calcium and vitamin D intake are adequate. Several studies even demonstrate some benefit to a plant-based diet (1,2).

Intake May Not Equate with Bone Density

A study comparing the bone health status of young vegetarians and omnivores found that although the vegan and vegetarian diets were lower in protein, calcium and vitamin D than the omnivores, there was no significant difference in bone mineral density between the groups (3). 

This indicates that it’s not the overall intake of these nutrients that affects bone health but other factors including absorption and other dietary and lifestyle factors.

It’s likely that dietary factors affect bone remodelling in multiple ways. Plant-based diets may:

• Alter macronutrient and micronutrient balance
• Have different prebiotic and probiotic effects on the gut microbiota
• Change the inflammatory and immune response.

The process of bone mineralization and resorption is complex and is affected by numerous factors, including diet. Although some dietary factors involved in bone health, such as calcium and vitamin D, are typically associated with dairy products, plant-based sources of these nutrients also supply other key nutrients involved in bone maintenance.

Healthy Diet for Bone Health

Whilst considerable efforts have been undertaken to work out which individual nutrients are needed for bone health it is important to remember that healthy bones cannot be made without a healthy, balanced and varied diet. Research into the effects of different dietary models on bone health concludes that a healthy diet, such as the Mediterranean diet, is associated with a lower risk for hip fractures and maintaining bone health in postmenopausal women (4,5).

For more information on how to maintain healthy bones see blogposts on Osteoporosis and Nutrients to Support Bone Health. For a delicious bone building superfood salad recipe see Quinoa Salad with Tahini Dressing.

References

1. 2015 May 11;7(5):3416-26. Comparison of correlates of bone mineral density in individuals adhering to lacto-ovo, vegan, or omnivore diets: a cross-sectional investigation. Knurick J R et al.

2. Curr Opin Endocrinol Diabetes Obes. 2020 Aug;27(4):248-252. Plant-based diets and bone health: sorting through the evidence. Hsu E.

3. Asia Pac J Clin Nutr. 2019;28(2):383-388. Young adult vegetarians in Shanghai have comparable bone health to omnivores despite lower serum 25(OH) vitamin D in vegans: a cross-sectional study. Xie L et al.

4. JAMA Intern Med. 2016 May 1;176(5):645-52. Dietary Patterns and Fractures in Postmenopausal Women: Results From the Women’s Health Initiative. Haring B et al.

5. Eur J Epidemiol. 2017 Jul;32(7):605-616. Long-term a posteriori dietary patterns and risk of hip fractures in a cohort of women. Warensjo E et al.