Are vegans & vegetarians at increased risk of poor bone health?
I take a look at the science behind whether vegans & vegetarians are at increased risk of poor bone health vs their meat & fish eating counterparts
Plant based diets
More and more people are turning towards a plant-based diet due to concerns around animal welfare and the environmental sustainability of meat & fish-based diets. Having been a vegetarian for over 26 years, I like to think my diet is balanced and that I achieve the recommended daily intakes of key nutrients often hard to achieve in vegetarian, and especially vegan diets, as their main sources are from meat & animal products (iron, calcium, vitamin B12, zinc).
Calcium & bone health
I am going to focus on calcium in this blog. Calcium cannot be made by the body, it is essential for strong bone health and is stored in our bones. The main sources of dietary calcium are milk/milk alternatives, bony fish and leafy green vegetables; it is recommended that adults over 19 years of age consume 700 milligrams (mg) of calcium every day to keep our bones healthy. The less calcium in our bones, the less dense and therefore more fragile our bones are.
Calcium intakes in vegetarians & vegans
An ongoing study of more than 30,000 British people found that average daily intakes of calcium amongst meat-eaters, fish-eaters, vegetarians and vegans all exceeded the recommended 700mg/day: ranging 848mg/day for vegans, 1,083mg/day for meat eaters, 1,117mg/day for vegetarians and 1,131mg/day for fish eaters.
However, these are averages and the data showed that around 15% of vegans had intakes below 525mg/day; while only 2% in the other groups were this deficient.
What does this mean?
These findings mean that, whilst many vegans can achieve adequate calcium in the diet, vegans must be mindful of consuming sufficient high-quality calcium sources to avoid deficiency. Insufficient calcium over time leads to softening of the bones (osteomalacia), followed by osteoporosis and increased risk of bone fracture. As our bones naturally lose density as we age, dietary intake is key in supporting healthy bone density.
A recent study of over 35,000 people worldwide found that both vegetarians and vegans aged over 50 years had lower bone density than meat and fish eaters. It is suggested that the natural bone density losses caused by ageing in these people may have been exacerbated by poor calcium intakes over their lifetime. The study also reported that vegans had an increased fracture risk vs vegetarians, meat & fish eaters.
What should I do as a vegan or vegetarian?
Whilst the studies reported poorer calcium intakes, poorer bone density and greater fracture risk in vegans, there are things we can do to encourage good bone health.
Both vegetarians and vegans should :
Consume calcium-rich foods such as low-fat milk/milk alternatives and small quantities of reduced-fat cheese. Cottage cheese, tofu, broccoli, cabbage, yoghurt and nuts are also good sources.
Undertake weight-bearing exercise in their weekly activity
Take a daily supplement of 10 micrograms of Vitamin D (as should everybody). Vitamin D helps us absorb calcium.
How can I help as a Nutritionist?
Contact me for a 1-1 telephone or Skype/video consultation to discuss whether your personal intake is sufficient, for recipe ideas and for suggestions to improve your overall diet and health.
1. Sobiecki et al., (2016), High compliance with dietary recommendations in a cohort of meat eaters, fish eaters, vegetarians, and vegans: results from the European Prospective Investigation into Cancer and Nutrition–Oxford study, Nutr Res, 36(5): 464–477. Doi: 10.1016/j.nutres.2015.12.016
2. Iguacel et al., (2018), Veganism, vegetarianism, bone mineral density, and fracture risk: a systematic review and meta-analysis, Nutrition Reviews, 77(1): 1-18. Doi: 10.1093/nutrit/nuy045
3. NICE.org.uk (2020), Vitamin D deficiency in adults - treatment and prevention. Available at: https://cks.nice.org.uk/vitamin-d-deficiency-in-adults-treatment-and-prevention#!scenario:1