Vitamin D: A Review on Its Effects on Muscle Strength, the Risk of Fall, and Frailty

Table 1

Summary of RCT and meta-analysis regarding effects of vitamin D on muscle function and falls.

Type of study	Author	Number of subjects	Type of subjects	Mean age (years)	Intervention	Duration	Results
RCT	Kenny et al. (2003) [48]	65	Healthy men	76	1,000 IU/d vitamin D versus placebo	6 months	No increase in muscle strength or improvement in physical performance.
RCT	Songpatanasilp et al. (2009) [11]	72	Postmenopausal females	70	Ca 1500 mg/d + alfacalcidol 0.5 ug/d versus Ca 1500 mg/d	12 weeks	Improvement in muscular strength.
RCT	Lips et al. (2010) [49]	226	Elderly males and females with vitamin D <50 nmol/L	77	8400 IU/week vitamin D versus placebo	16 weeks	Improvement of balance in a subgroup with severe balance impairment at baseline.
RCT	Ward et al. (2010) [46]	69	Postmenarchal females (12 to 14 years old) with vitamin D <25 nmol/L	13	4 doses of 150,000 IU vitamin D every 3 months versus placebo	12 months	Increase in jump velocity in girls with low vitamin D levels.; No improvement in strength in others.
RCT	Gupta et al. (2010) [44]	40	Healthy males and females	31	60,000 IU/week for 8 weeks followed by 60,000 IU/month for 4 months vitamin D + 1000 mg Ca/d versus placebo	6 months	Enhanced skeletal muscle strength and physical performance.
RCT	Zhu et al. (2010) [45]	300	Elderly females with vitamin D <60 nmol/L	77	1,000 IU/d vitamin D + Ca 1000 mg/d versus Ca 1000 mg/d + placebo	12 months	Enhanced skeletal muscle strength and physical performance in patient with the lowest vitamin D level.
RCT	Taskapan et al. (2011) [39]	25 (CKD stages 3-4); 47 (PD)	CKD and PD with vitamin D <50 nmol/L	NA	50000 IU/week vitamin D	4 to 8 weeks	Improvement in physical performance tests.
UCT	Schacht and Ringe (2012) [56]	2100	Males and postmenopausal females	75	1 mcg/d calciferol	6 months	Improved physical performance.
RCT	Glendenning et al. (2012) [52]	690	Elderly females (age >70)	77	150,000 IU/every 3 months vitamin D versus placebo	9 months	No differences in falls and physical performance between the groups.
RCT	Goswami et al. (2012) [53]	173	Healthy females	22	60,000 IU/week every 8 weeks then 60, 000 IU/fortnight + Ca 500 mg/d versus 60,000 IU/week every 8 weeks then 60, 000 IU/fortnight + placebo versus Ca 500 mg/d + placebo versus placebo	6 months	No differences in muscle strength between the groups.
RCT	Ceglia and Harris (2013) [21, 27]	21	Females with limited mobility	78	4000 IU/d vitamin D	4 months	Increase of intramyonuclear VDR concentration. Increase in muscle fibers.
RCT	Wyon et al. (2014) [47]	24	Elite ballet dancers	28	2000 IU/d vitamin D versus placebo	4 months	Increased muscle performance and less injury.
Meta	Muir and Montero-Odasso (2011) [54]	2268 (13 RCTs)	Elderly males and females (age >65)	78	Vitamin D supplementation		Beneficial effects on strength and balance.
Meta	Stockton et al. (2011) [55]	5072 (17 RCTs)	Males and females of all ages	NA	Vitamin D supplementation		Increase in muscle strength in adults with baseline vitamin D <25 nmol/L.
RCT	Bischoff et al. (2003) [63]	122	Elderly females	85	Ca 1200 mg and 800 IU/d vitamin D versus Ca 1200 mg/d	12 weeks	Reduced risk of fall.
RCT	Pfeifer et al. (2009) [62]	242	Community-dwelling elderly males and females	77	800 IU/d vitamin D + Ca 1000 mg/d versus Ca 1000 mg/d	12 months	Reduced number of falls and improvement in muscle function.
Meta	Gillespie (2003)	461 (3 RCTs)	Elderly males and females	NA	Vitamin D supplementation		No reduction in the risk of fall.
Meta	Bischoff-Ferrari et al. (2004) [66]	10001 (10 RCTs with sensitivity analysis); 1237 (5 RCTs without sensitivity analysis)	Elderly males and females, age >65	70	Vitamin D supplementation		Reduced risk of fall.
Meta	Michael et al. [64] (2010)	5809 (9 RCTs)	Elderly males and females	NA	Vitamin D supplementation		Reduced risk of fall.
Meta	Murad et al. (2011) [65]	45782 (26 RCTs)	Males and females (all ages)	NA	Vitamin D + Ca supplementation		Reduced risk of fall.

RCT: randomized control trial, UCT: uncontrolled trial,Meta: meta-analysis, NA: nonavailable, CKD: chronic kidney disease, PD: peritoneal dialysis, VDR: vitamin D receptor, and Ca: calcium.