Why Vegans Could Be at Risk of Bone Fractures

December 09, 2020 by Joel Fuhrman, MD


Oxford study reveals potential pitfalls 

A study published in November 2020 on 54,898 people living in the UK,1982 of whom were vegan, found a greater risk of total and hip fractures in vegans compared to meat eaters after an average follow-up of 17.6 years.1 

Source:  Vegetarian and vegan diets and risks of total and site-specific fractures: results from the prospective EPIC-Oxford study

Excluding animal products does not guarantee health

The authors were able to attribute some of the risk of fractures to low BMI and lower calcium and protein intakes among vegans. A relatively large number of vegans – 17% of vegan men and 28% of vegan women – had BMI below 20, which might indicate illness or low muscle mass and could negatively affect bone density. Notably, when they divided the vegans into groups by BMI, a significantly higher risk of total and hip fractures was only found in vegans with BMI below 22.5.  Of course, overweight people carrying more weight have bigger muscles and bones and less fractures—but they don’t live as long.2,3   The question remains, can we get enough protein for excellent muscle and bone density, maintain a lifespan favorable BMI and still prevent fractures. 

In this study, the average protein intake was 12.9% and 13.5% of calories for vegan men and women (which may be a bit low for the elderly) and 16.0% and 17.3% for meat eaters. Calcium intake was 1058 and 989 mg/day for meat eating men and women and 611 and 580 mg/day for vegan men and women. This low calcium intake likely reflects insufficient green vegetable intake by the vegans in the study. 

The study’s disclaimer

The authors noted these factors – BMI, calcium intake, and protein intake – did not fully explain the difference in fracture risk between meat eaters and vegans, saying additional unknown factors likely also contributed. 

For example, the researchers had no information on what supplements participants were taking or what type of exercise they engaged in. Rates of regular exercise were low in all groups but higher in vegans; 29% of meat eaters and 41% of vegans reported engaging in “moderate or high physical activity.” 

Other contributors to bone health

Insufficient vitamin D, strength training, or intake of green vegetables and other bone-protecting plant foods could potentially be contributors.  In other studies, diets higher in vegetables, fruits, minerals, and phytochemicals are linked to better bone health.4-6

Related: Preventing Osteoporosis

Plant protein from beans, nuts, and seeds

Vegans did consume more legumes, nuts, vegetables, and fruits than meat eaters, but on average, vegetable intake was only 173-200 g/day, which is less than two cups of vegetables daily. 

Average legume intake was 30 g/day, which is only one-sixth of one cup of beans or lentils. Average intake of nuts was less than one ounce/day, and seed intake was not mentioned in the study. This low intake of whole plant foods suggests the vegans in the study were likely getting too many calories from refined carbohydrates and processed foods. 

More plant protein improves health and lifespan 

Certainly, the evidence is conclusive that a high-animal protein diet increases cancer risk and shortens lifespan,7-11 but we need sufficient protein to support muscle growth and bone mass, especially as we get older.12 One important thing to note is that older adults are most vulnerable to bone loss, osteoporosis, and fractures as absorption and assimilation of protein and calcium decreases with aging, increasing their protein and calcium requirements compared to younger people. 

The Nutritarian difference

A Nutritarian diet may be low in animal protein, but it contains more plant protein compared to most other plant-based diets. Getting enough protein on a vegan diet isn’t difficult, but it does require attention to nutritional variety. Relying on high-glycemic, low-protein foods like refined carbohydrates, rice, and potatoes for most of your calories will likely result in inadequate protein as well as a high glycemic load, which is also detrimental to bone health. A higher blood glucose level is not good for the bones.13,14 

Other high-credence studies with large numbers of participants have corroborated this—that more protein-rich plant foods lead to better health and longer lifespan and more protein-rich animal products leads to worse health outcomes and shorter lifespan.11,15-19   The secret sauce here is to eat more protein-adequate plant foods.  

A diet with a variety of plant protein sources – beans (including soybeans), seeds, nuts, and vegetables – provides adequate (but not excessive) amounts of protein and a more complete array of each essential amino acid.20 Certain plant foods are higher or lower in certain essential amino acids, and a variety of foods ensures we don’t have a low intake of any particular one; this is important for bone health since certain essential amino acids, including lysine – which is higher in legumes than many other plant foods – may facilitate collagen formation.20-22 

Protein needs are greater for adults over approximately age 70.23, 24  In addition to increasing legumes and seeds, older adults who experience loss of bone or muscle mass with aging might consider adding a plant-based protein supplement (pea, hemp, or pumpkin protein) or a small amount of animal protein, such as an egg white, if needed to help maintain muscle mass and strength. 

Previous data on bone health in vegans, vegetarians, and non-vegetarians from the Adventist Health Study suggests adequate protein intake is an important strategy for preventing fractures. Greater plant protein intake was associated with a lower risk of wrist fractures in vegetarian women, and greater intake of legumes and meat substitutes were associated with a lower risk of hip fractures in men and women.22, 25

Calcium-rich foods

Most people do no consume enough calcium-rich plant foods, such as beans and green vegetables. Bone tissue is made up of mostly calcium phosphate and collagen, with 99% of the calcium in the body stored in our bones. Adequate dietary calcium is necessary for strong bones. Although dairy products are not health-promoting, non-vegans most often get adequate calcium because of dairy intake. Plant foods can provide adequate calcium (along with other minerals, vitamins, fiber, and phytochemicals), but vegans must pay attention to eating these calcium-rich foods. How much calcium we absorb varies depending on the food source, as you can see in the table below.26  
 

Note: Tofu is prepared with calcium sulfate or magnesium chloride and calcium sulfate (sometimes called nigari). Check the Nutrition Facts panel for calcium content.

Nutritarian diet vs. starch-based vegan diet

Supplements: vitamin D and K2

In the study outlined above, the researchers did not have data on what supplements the participants took. It is possible that lack of supplementation, especially of vitamin D, could have contributed to the elevated fracture risk in vegans in the study.

About 35% of Americans do not meet the recommended intake of vitamin K, and for vitamin D, the number is even larger – 70% don’t meet the recommended intake daily.30  Nevertheless, it was unlikely the vegans were more deficient in Vitamin D, compared to the meat-eating cohort, though it still is something to be aware of.  Vitamin D is important for bone health because it regulates absorption of calcium and phosphorus, which are major components of bone tissue. Deficiency in vitamin D increases the risk of fractures.31,32 

A vast amount of research supports a blood concentration of vitamin D (as measured by 25(OH)D) in the 30-45 ng/ml range for fracture prevention.33 I recommend most people supplement to achieve such a blood level, so they can avoid excessive skin aging and skin damage from too much sun exposure.  2000 IU (50 mcg) is an appropriate dose for most adults to be able to achieve this favorable range in the blood.  Awareness of all components that can affect fracture risk and falls is important.  

Related: Vitamin D is Crucial to Overall Health

Green vegetables are the richest source of vitamin K1; vitamin K2 is produced by microorganisms and is low in plant foods. Supplementation trials using vitamin K2 in postmenopausal women have found notable reductions in fracture risk: a 60% reduction in vertebral fracture, 77% for hip fracture, and 81% for all non-vertebral fractures. 34, 35 I recommend getting K1 from green vegetables and supplementing with a moderate dose of K2 to help maintain bone density with aging.  

Related: What is vitamin K? Do I need both K1 and K2?

Appropriate calcium supplementation

For many people, green vegetables, beans, nuts, and seeds most likely provide enough calcium without the need for supplements. However, calcium requirements are higher for certain groups. Pregnant, nursing, and postmenopausal women, as well as those with osteopenia or osteoporosis and those with a small appetite for green vegetables might consider adding a small dose of supplemental calcium, spread out with each meal to ensure sufficient calcium intake. I recommend using lower dose, food-derived calcium supplements (whole powdered seaweed, for example), at a dose of 200-300 mg/meal) to add to the calcium already in the meal, thus avoiding a huge amount of concentrated calcium coming in all at once.  So I do not recommend high-dose (1000 mg or more) calcium supplements, because there is preliminary (though still inconclusive) evidence that those high doses may be harmful to the cardiovascular system.36,37

Related: High-dose calcium supplements may damage the cardiovascular system

Exercise

Food provides the raw material, but exercise is essential for building muscle and maintaining bone mass.
Strength training and weight-bearing exercise (such as running and jumping) are effective at building bone strength.38-40 These types of exercise stimulate activity in bone-building cells, leading to denser, stronger bones.

Related: Exercise is essential for heart health, slowing aging, and cognitive function

The meat of the story

The conclusion here is that the recent findings that vegans are at higher risk of fractures is consistent with other studies that show that paying attention to plant protein is important for those following vegan diets.   A Nutritarian diet is the gold-standard of plant-based diets as the dietary portfolio is rich in the most health and longevity-promoting foods—which are also good for the bones.  The evidence is clear – to  assure excellent health and longevity the intelligent and conservative use of some supplements is indicated. 

Let’s face reality here—a healthier diet is healthier than one that is less healthy.   As ridiculous as that sounds many people are trying to pawn off the idea that even a haphazardly designed diet is fine as long as you don’t eat animal products. The facts point to the conclusion that many vegans are not eating healthfully enough.  I hope that’s not you.  
 

 
References
  1. Tong TYN, Appleby PN, Armstrong MEG, et al. Vegetarian and vegan diets and risks of total and site-specific fractures: results from the prospective EPIC-Oxford study. BMC Med 2020, 18:353.

  2. Yu E, Ley SH, Manson JE, et al. Weight History and All-Cause and Cause-Specific Mortality in Three Prospective Cohort Studies. Ann Intern Med 2017, 166:613-620.

  3. Global BMC, Di Angelantonio E, Bhupathiraju Sh N, et al. Body-mass index and all-cause mortality: individual-participant-data meta-analysis of 239 prospective studies in four continents. Lancet 2016, 388:776-786.

  4. Tucker KL, Hannan MT, Chen H, et al. Potassium, magnesium, and fruit and vegetable intakes are associated with greater bone mineral density in elderly men and women. Am J Clin Nutr 1999, 69:727-736.

  5. New SA, Robins SP, Campbell MK, et al. Dietary influences on bone mass and bone metabolism: further evidence of a positive link between fruit and vegetable consumption and bone health? Am J Clin Nutr 2000, 71:142-151.

  6. Sacco SM, Horcajada MN, Offord E. Phytonutrients for bone health during ageing. Br J Clin Pharmacol 2013, 75:697-707.

  7. Huang, Jiaqi, PhD, et al. Association Between Plant and Animal Protein Intake and Overall and Cause-Specific Mortality. JAMA Internal Medicine 2020, 180:1173-1184.

  8. Levine ME, Suarez JA, Brandhorst S, et al. Low protein intake is associated with a major reduction in IGF-1, cancer, and overall mortality in the 65 and younger but not older population. Cell Metab 2014, 19:407-417.

  9. Lagiou P, Sandin S, Lof M, et al. Low carbohydrate-high protein diet and incidence of cardiovascular diseases in Swedish women: prospective cohort study. BMJ 2012, 344:e4026.

  10. Key TJ. Diet, insulin-like growth factor-1 and cancer risk. Proc Nutr Soc 2011:1-4.

  11. Song M, Fung TT, Hu FB, et al. Association of Animal and Plant Protein Intake With All-Cause and Cause-Specific Mortality. JAMA Intern Med 2016, 176:1453-1463.

  12. Campbell WW, Trappe TA, Wolfe RR, Evans WJ. The recommended dietary allowance for protein may not be adequate for older people to maintain skeletal muscle. J Gerontol A Biol Sci Med Sci 2001, 56:M373-380.

  13. Levinger I, Seeman E, Jerums G, et al. Glucose-loading reduces bone remodeling in women and osteoblast function in vitro. Physiol Rep 2016, 4.

  14. Oei L, Zillikens MC, Dehghan A, et al. High bone mineral density and fracture risk in type 2 diabetes as skeletal complications of inadequate glucose control: the Rotterdam Study. Diabetes Care 2013, 36:1619-1628.

  15. Virtanen HEK, Koskinen TT, Voutilainen S, et al. Intake of different dietary proteins and risk of type 2 diabetes in men: the Kuopio Ischaemic Heart Disease Risk Factor Study. Br J Nutr 2017, 117:882-893.

  16. Tharrey M, Mariotti F, Mashchak A, et al. Patterns of plant and animal protein intake are strongly associated with cardiovascular mortality: the Adventist Health Study-2 cohort. Int J Epidemiol 2018.

  17. Budhathoki S, Sawada N, Iwasaki M, et al. Association of Animal and Plant Protein Intake With All-Cause and Cause-Specific Mortality. JAMA Intern Med 2019.

  18. Huang J, Liao LM, Weinstein SJ, et al. Association Between Plant and Animal Protein Intake and Overall and Cause-Specific Mortality. JAMA Intern Med 2020.

  19. Naghshi S, Sadeghi O, Willett WC, Esmaillzadeh A. Dietary intake of total, animal, and plant proteins and risk of all cause, cardiovascular, and cancer mortality: systematic review and dose-response meta-analysis of prospective cohort studies. BMJ 2020, 370:m2412.

  20. Young VR, Pellett PL. Plant proteins in relation to human protein and amino acid nutrition. Am J Clin Nutr 1994, 59:1203S-1212S.

  21. Jennings A, MacGregor A, Spector T, Cassidy A. Amino Acid Intakes Are Associated With Bone Mineral Density and Prevalence of Low Bone Mass in Women: Evidence From Discordant Monozygotic Twins. J Bone Miner Res 2016, 31:326-335.

  22. Lousuebsakul-Matthews V, Thorpe DL, Knutsen R, et al. Legumes and meat analogues consumption are associated with hip fracture risk independently of meat intake among Caucasian men and women: the Adventist Health Study-2. Public Health Nutr 2014, 17:2333-2343.

  23. Volpi E, Campbell WW, Dwyer JT, et al. Is the optimal level of protein intake for older adults greater than the recommended dietary allowance? J Gerontol A Biol Sci Med Sci 2013, 68:677-681.

  24. Bauer J, Biolo G, Cederholm T, et al. Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. J Am Med Dir Assoc 2013, 14:542-559.

  25. Thorpe DL, Knutsen SF, Beeson WL, et al. Effects of meat consumption and vegetarian diet on risk of wrist fracture over 25 years in a cohort of peri- and postmenopausal women. Public Health Nutr 2008, 11:564-572.

  26. Weaver CM, Plawecki KL. Dietary calcium: adequacy of a vegetarian diet. Am J Clin Nutr 1994, 59:1238S-1241S.

  27. USDA Food Data Central [https://fdc.nal.usda.gov/index.htmlt]

  28. Mangels R, Messina G, Messina M: The Dietitian's Guide to Vegetarian Diets. Jones & Bartlett; 2011.

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  30. Fulgoni VL, 3rd, Keast DR, Bailey RL, Dwyer J. Foods, fortificants, and supplements: Where do Americans get their nutrients? J Nutr 2011, 141:1847-1854.

  31. Brincat M, Gambin J, Brincat M, Calleja-Agius J. The role of vitamin D in osteoporosis. Maturitas 2015, 80:329-332.

  32. Holick MF. Sunlight and vitamin D for bone health and prevention of autoimmune diseases, cancers, and cardiovascular disease. American Journal of Clinical Nutrition 2004, 80:1678S-1688S.

  33. Bischoff-Ferrari HA. Vitamin D and fracture prevention. Rheumatic Diseases Clinics of North America 2012, 38:107-113.

  34. Feskanich D, Weber P, Willett WC, et al. Vitamin K intake and hip fractures in women: a prospective study. Am J Clin Nutr 1999, 69:74-79.

  35. Cockayne S, Adamson J, Lanham-New S, et al. Vitamin K and the prevention of fractures: systematic review and meta-analysis of randomized controlled trials. Arch Intern Med 2006, 166:1256-1261.

  36. Bhattacharya RK. Does widespread calcium supplementation pose cardiovascular risk? No: concerns are unwarranted. Am Fam Physician 2013, 87:Online.

  37. Reid IR, Bolland MJ. Does widespread calcium supplementation pose cardiovascular risk? Yes: the potential risk is a concern. Am Fam Physician 2013, 87:Online.

  38. Rubin C, Turner AS, Muller R, et al. Quantity and quality of trabecular bone in the femur are enhanced by a strongly anabolic, noninvasive mechanical intervention. Journal of Bone and Mineral Research 2002, 17:349-357.

  39. Marques EA, Mota J, Machado L, et al. Multicomponent training program with weight-bearing exercises elicits favorable bone density, muscle strength, and balance adaptations in older women. Calcified Tissue International 2011, 88:117-129.

  40. Howe TE, Shea B, Dawson LJ, et al. Exercise for preventing and treating osteoporosis in postmenopausal women. Cochrane Database Syst Rev 2011:CD000333.

Joel Fuhrman, M.D. is a board-certified family physician, seven-time New York Times bestselling author and internationally recognized expert on nutrition and natural healing, who specializes in preventing and reversing disease through nutritional methods. Dr. Fuhrman coined the term “Nutritarian” to describe his longevity-promoting, nutrient dense, plant-rich eating style.
 
For over 25 years, Dr. Fuhrman has shown that it is possible to achieve sustainable weight loss and reverse heart disease, diabetes and many other illnesses using smart nutrition. In his medical practice, and through his books and PBS television specials, he continues to bring this life-saving message to hundreds of thousands of people around the world.

 

Comments (0):

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catherine309y

12/10/2020 04:24 PM

Have you got any thoughts about Camelina seeds as an Omega 3 source?

vaporz replies:

12/17/2020 05:19 PM

They are a great source of Omega-3's with roughly the same amount as walnuts per ounce.

susan88

12/10/2020 05:10 PM

thanks so much we walk to work i mile and back every day and we take what you said thank you

TinaRuns

12/10/2020 06:57 PM

This is an excellent article. Thank you for writing it. Unfortunately, as someone who religiously followed a mostly vegetable + bean plant-based diet for 3 years (after reading all of your books, and several similar from other authors), and a healthy distance runner, with a healthy diet for most of my life, I was shocked when my doctor told me that he thought I had what looked like osteopenia developing.  (I'm 51; something similar happened to my husband, who is also lean & healthy.)  So we switched to adding small amounts of meat protein in our diet, with small amounts of dairy, too.  I still don't think I eat nearly enough calcium and that concerns me.  The difficulty is that remembering all of these details is not easy.  I really think the plant-based diet is a problem for our bones.  Then again, I am fully convinced that a heavy meat diet contributes to every other disease.  So it seems like there is no winning.

This comment was last edited on 12/10/2020 06:58 PM

Isabelle55 replies:

12/19/2020 03:29 AM

Fast forward 10 years. At 62 my spine is -2.1, not osteoporosis yet but full-blown osteopoenia. I love Dr Fuhrman and am so grateful to him for his work. Also I honestly believe that if I up my plant protein I might be fine.  However, I need to hedge my bets as I cannot take any risk on this.  Osteo runs in my family so I am adding very small amounts of animal protein.   I also came across this great comment in the New York Times on the same subject (this oxford study). **eat only plant based foods except for fish, usually canned sardines or mackerel. But, I don't tell anyone I am a 90% "vegan"; I say I'm a "nutritarian", a term coined by Dr. Joel Fuhrman. Vegan means simply that you avoid all animal based foods, but you can be a vegan and consume junk food and food that had nutrients and fiber processed out. I've been on a plant based diet for 8 years and that plus plenty of intense physical activity has helped me be a healthy, vigorous 83 year old guy. I suggest getting into books by Fuhrman.**

Lovewins1

12/11/2020 06:37 AM

Thank you, you are my champion for maintaining good health.  Would you please consider making magnets of the food charts and secondly, could you please do a study, paper on gaining & maintaining good eye health.  Thank you so much, m Salenger

 

GEBoyer2

12/11/2020 10:44 AM

Thank you for your words of wisdom.  I really value your advice and try to follow it. I am 77 years old and have osteoporosis in my spine and osteopenia in my hip. It is a struggle to know the best solution for my situation.    

Organic Traveler

12/11/2020 03:07 PM

Thank you for this timely article that provides exactly the information I was looking for and questions I have been asked by members of the National Health Association.  I will be forwarding this article which provides such valuable information.  

 

vaporz

12/18/2020 12:40 PM

The Nutritarian menu listed here is also very high fiber (62.5 grams) and low sodium (539 grams).  Conversely, Starch diets like McDougall's are high in sodium and not high in fiber.

This comment was last edited on 12/18/2020 01:13 PM

HealthyMeredith

01/02/2021 01:35 AM

How is bone density checked? And at what regular intervals throughout life?

RDanker694 replies:

01/04/2021 10:42 PM

My doctor takes a bone scan every 2 years with a DEXA machine, because I have osteoporosis. (DEXA stands for dual energy x-ray absorptiometry.) If your bone scan comes back okay, then you probably wouldn't need it taken that often.