New studies tout the respiratory and cognitive benefits of vitamin D.
Researchers found that calcitriol, a form of vitamin D synthesized in the body, helps curb airway remodeling in people with asthma. Airway remodeling eventually reduces lung function. The results were reported in San Diego at the American Thoracic Society 105th International Conference.
Cells from 12 subjects were used to compare calcitriol with dexamethasone. Although a powerful anti-inflammatory agent, dexamethasone had little effect on the growth of human airway smooth muscle. Preliminary evidence indicates that calcitriol may also slow airway remodeling in people with chronic obstructive pulmonary disease.
Another study links vitamin D and cognitive performance in middle-aged and older men. Researchers examined the association between 25-hydroxyvitamin D (25[OH]D) levels and cognitive performance in 3,133 men aged 40-79 years who were enrolled in the European Male Ageing Study. The men who had lower levels of 25(OH)D performed more poorly on the Digit Symbol Substitution test, a measure of cognitive function (J Neurol Neurosurg Psychiatry. 2009; published online ahead of print).