Vitamin D: More than just a vitamin

While many think of vitamin D as a just another vitamin, the reality is that it is a strong hormonal regulator. The body produces vitamin D from direct exposure to sunlight which trigger synthesis of vitamin D. Vitamin D can also be obtained from food sources and through supplementation. One of the main roles of Vitamin D is to promote calcium absorption and is involved in the formation of new bone. The true significance of vitamin D as a regulator of other functions including modulating cell formation, immune function, and reducing inflammation within the body, has come to light in many recently published studies.

Evidence:

In one of the most recent publications, researchers looked at vitamin D levels in children and teenagers and found that those with low levels had greater risks of atherosclerosis as adults. This study included over 2148 volunteers who had vitamin D levels during childhood years and then had carotid intima-thickness assessed between the ages of 30 to 45. Thickening of the arteries is believed to be a strong risk factor for cardiovascular disease

Juonala M, Voipio A, Pahkala K, Viikari JS et al. Childhood 25-OH levels Vitamin D Levels and Carotid Intima-Media Thickness in Adulthood: The Cardiovascular Risk in Young Finns Study. Journal of Endocrinology and Metabolism. 2015 Feb 10.

Taken from a randomized, double blind, placebo controlled study that was published in the American Journal of Clinical Nutrition looking at the role of Vitamin D in preventing influenza, the group that was given 1200 IU of Vitamin D3 had comparatively lower rates of flu (influenza A) versus placebo. The study also suggested lowered rates of asthma attacks in children.

Urashima M, Segawa T, Okazaki M, Kurihara M, Wada Y, Ida H. Randomized trial of Vitamin D supplementation to prevent seasonal influenza A in schoolchildren. American Journal of Clinical Nutrition. 2010 May; 91(5): 1255-1260.

In a 2014 published study from the University of London, researchers conducted a randomized trial, looking at the use of Vitamin D levels in patients with COPD. The findings of this study which included 240 patients showed that adequate Vitamin D supplementation can reduce COPD flare-ups by 40%

Martineau AR, James WY, Hooper RL, Barnes NC, Jolliffe DA et al. Vitamin D3 supplementation in patients with chronic obstructive pulmonary disease (ViDico): a multicentre double blind, randomized control trial. The Lancet. Respiratory Medicine. 2014 Dec 1. Pii: S2213-2600(14).

A recent study (2015) presented at the American Stroke Association’s annual meeting that looked at 100 patients who suffered an ischemic stroke. Those with low levels of Vitamin D (<30 ng/mL had a greater risk of developing a stroke and had approximately a two times greater area of stroke related brain dead tissue versus those with normal vitamin D levels. http://newsroom.heart.org/news/low-vitamin-d-predicts-more-severe-strokes-poor-health-post-stroke

Researchers from the University of California published a meta-analysis that encompassed over 32 studies that looked at Vitamin D levels and mortality. The findings show that those with inadequate Vitamin D levels (< 30 ng/mL) were 90% more likely to die prematurely when compared with those who had levels over 30 mg/Ml

Garland CF, Kim JJ, Mohr SB, Gorham ED, Grant WB, Givannuci El, Baggerly L, Hofflich H, Ramsdell JW, Zeng K, Heaney RP. Meta-analysis of all-cause mortality according to serum 25-hydroxvitamin D. American Journal of Public Health. 2014 Aug; 104(8):e43-50.

These are just a handful of the studies looking at the interaction between levels of Vitamin D and various disease processes.