by Ronald G. Reichert, ND
Since earning his doctorate in naturopathic medicine from Bastyr University in 1989, Dr Ronald Reichert has worked as an expert consultant to the natural health products industry. In addition to maintaining a private practice, he is an adjunct professor at the Boucher Institute for Naturopathic Medicine, and the Director for Scientific Affairs at the Canadian Centre of Functional Medicine.
A recent meta-analysis by Dr. Bolland published in the British journal Lancet Diabetes-Endocrinology (2018) concludes that “vitamin D supplementation does not prevent fractures or falls, or have clinically meaningful effects on bone mineral density.” Unfortunately this conclusion is premature according to several prominent scientists.
Dr. Robert Clarke, a professor of epidemiology and public health at the University of Oxford noted that, “the report included all available trials of vitamin D, but such trials included too few participants, used an insufficient dose of vitamin D, and had an insufficient duration of treatment.” He goes on to conclude that “the study lacked the ability to reliably test the effects of vitamin D on risk of hip fracture. So, it is too soon to suggest making changes to health recommendations on vitamin D for bone health based on this study.”
Major Limitations: Those who stood to gain most in the minority
In addition, Professor Adrian Martineau, Clinical Professor of Respiratory Infection and Immunity, Queen Mary University of London, found that “a major limitation of this study is that people with low vitamin D levels (i.e. 25-hydroxyvitamin D <25 nmol/L) – who potentially stand to benefit the most from supplementation – were in a small minority in the trials that were included in the analysis. Moreover, the authors failed to obtain data from individual trial participants for their meta-analysis. This limited their ability to determine whether individuals with low baseline vitamin D levels benefit more from vitamin D supplementation than those with higher baseline levels.” (1)
Other researchers have noted that the use of vitamin D3 is an important factor in the bone health of elderly women. In their meta-analysis they found that the use of vitamin D3 at a dose of 800 IU daily reduces the incidence of osteoporotic non-vertebral, hip, and non-vertebral-non-hip fractures.” (2) This is particularly true when vitamin D is combined with calcium as vitamin D is critical for calcium absorption. (3)
Other studies show significant risk reduction from taking D
Another meta-analysis involving over 30,970 participants found that “calcium plus vitamin D supplementation produced a statistically significant 15 % reduced risk of total fractures and a 30 % reduced risk of hip fractures.”(4) In addition, vitamin D supplementation helps supports bone mineral density. Vitamin D3 supplementation at 1000 IU per day significantly reduces the rate of hip bone loss over a 1 year time period in post-menopausal women.(5) Moreover, the use of vitamin D helps reduce fall risk in the elderly.
Research lead by Dr. R.R. Kalyani and his team from the Division of Endocrinology and Metabolism, Department of Medicine at Johns Hopkins University School of Medicine concluded that the use of vitamin D (200-1,000 IU) resulted in 14% fewer falls than calcium or placebo in older adults.(6)
Bones not the only benefit for Canadians
Vitamin D also play an important role in several other types of health issues including the reduction of inflammation and oxidative stress in diabetics (7), decreases pain in those with chronic pain (8), and reduces the risk of acute upper respiratory infections (9).
Statistics Canada has found that about 32% of Canadians had blood concentrations of vitamin D that were less than the cut off value of 50 nmol/L—a level that is needed for healthy bones for most individuals (10). This latter fact, in conjunction with robust scientific evidence, reinforces the importance of vitamin D supplementation in musculoskeletal and other health concerns.
- Bergman GJ, Fan T, McFetridge JT, Sen SS. Efficacy of vitamin D3 supplementation in preventing fractures in elderly women: a meta-analysis. Curr Med Res Opin. 2010;26:1193-201.
- Aloia JF, Dhaliwal R, Shieh A, Mikhail M, Fazzari M, Ragolia L, Abrams SA. Vitamin D supplementation increases calcium absorption without a threshold effect. Am J Clin Nutr. 2014 ;99:624-31.
- Weaver CM, Alexander DD, Boushey CJ, Dawson-Hughes B, Lappe JM, LeBoff MS, Liu S, Looker AC, Wallace TC, Wang DD. Calcium plus vitamin D supplementation and risk of fractures: an updated meta-analysis from the National Osteoporosis Foundation. Osteoporos Int. 2016 ;27:367-76.
- Macdonald HM, Wood AD, Aucott LS, Black AJ, Fraser WD, Mavroeidi A, Reid DM, Secombes KR, Simpson WG, Thies F. Hip bone loss is attenuated with 1000 IU but not 400 IU daily vitamin D3: a 1-year double-blind RCT in postmenopausal women. J Bone Miner Res. 2013;28:2202-13.
- Kalyani RR, Stein B, Valiyil R, Manno R, Maynard JW, Crews DC. Vitamin D treatment for the prevention of falls in older adults: systematic review and meta-analysis. J Am Geriatr Soc. 2010 ;58:1299-310.
- Mansournia MA, Ostadmohammadi V, Doosti-Irani A, Ghayour-Mobarhan M, Ferns G, Akbari H, Ghaderi A, Talari HR, Asemi Z. The Effects of Vitamin D Supplementation on Biomarkers of Inflammation and Oxidative Stress in Diabetic Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Horm Metab Res. 2018 Jun;50(6):429-440.
- Wu Z, Malihi Z, Stewart AW, Lawes CM, Scragg R. Effect of Vitamin D Supplementation on Pain: A Systematic Review and Meta-analysis. Pain Physician. 2016;19:415-27.
- Martineau AR, Jolliffe DA, Hooper RL, Greenberg L, Aloia JF, Bergman P, Dubnov-Raz G, Esposito S, Ganmaa D, Ginde AA, Goodall EC, Grant CC, Griffiths CJ, Janssens W, Laaksi I, Manaseki-Holland S, Mauger D, Murdoch DR, Neale R, Rees JR, Simpson S Jr, Stelmach I, Kumar GT, Urashima M, Camargo CA Jr. Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data. BMJ. 2017 Feb 15;356:i6583.