Amyotrophic lateral sclerosis (ALS)
ALS affects anterior horn cells of the spinal cord causing an indolent slow and steady deterioration of muscle strength leading to respiratory failure. The following study evaluates the role of respiratory exposure to mercury from different sources as a suspected cause.
Vitamin D and ALS
In a study of 37 patients with amyotrophic lateral sclerosis (ALS) (median age: 55 years; median symptom onset: 61 months), researchers found that vitamin D supplementation (2,000 international units daily) was safe over a period of 9 months and may have a beneficial effect on ALSFRS-R scores. Further studies are recommended to determine whether there is a benefit in vitamin D supplementation for all ALS patients.
http://www.sciencedirect.com/science/article/pii/S0967586813001495
Note: research indicates that Vitamin D influences respiratory health. Vitamin D is now known to be of physiological importance outside of bone health and calcium homeostasis, and there is mounting evidence that it plays a beneficial role in the prevention and/or treatment of a wide range of diseases. Vitamin D appears capable of inhibiting pulmonary inflammatory responses while enhancing innate defence mechanisms against respiratory pathogens.