Vitamin D may reduce the risk of premature death
Vitamin D: Lower Risk of Premature Death
High serum concentrations of vitamin D are associated with a significantly reduced risk of premature mortality. Individuals with at least 30 nanograms per milliliter of 25[OH]D, a precursor of vitamin D, have about half the risk of dying early compared to those with lower levels.
This finding comes from a study published in the American Journal of Public Health. Researchers at the University of San Diego, California, analyzed numerous studies conducted over recent years on the relationship between vitamin D levels and mortality.
The Sunshine Vitamin
Vitamin D is a fat-soluble molecule involved in calcium and phosphorus metabolism, existing in two forms: cholecalciferol (Vitamin D3) and ergocalciferol (Vitamin D2). Dietary intake often fails to meet daily requirements, with only certain fish such as cod, tuna, salmon, and sardines providing notable amounts. Approximately 90% of the vitamin D in the human body is produced via skin exposure to ultraviolet sunlight. Both forms undergo two transformations in the body: first in the liver forming 25(OH)D, then in the kidney producing 1,25(OH)D, the active hormone that increases intestinal calcium absorption, regulates bone resorption, and manages phosphorus reabsorption in the kidneys.
Vitamin D Reduces Risk of Premature Death from All Causes
The researchers reviewed 32 studies published between 1996 and 2013, covering data from 566,583 men and women. Results showed that a serum vitamin D level of 30 ng/ml correlates with a 50% reduction in risk of death compared to lower concentrations. About two-thirds of the American population has this level of vitamin D. Previous studies had indicated that levels below 20 ng/ml increased risk of bone disease, but this new analysis broadens the threshold by linking low vitamin D to premature death from all causes.
Appropriate Vitamin D Doses Benefit Health
Heather Hofflich, a researcher at the University of San Diego, states this study should assure medical professionals and the public that vitamin D is safe when used in appropriate doses—up to 4,000 IU daily (about 100 μg). Nonetheless, it is advisable to consult a doctor before increasing vitamin D intake and to have annual blood tests to monitor 25-hydroxyvitamin D levels.
Source: Cedric F. Garland et al., “Meta-analysis of All-Cause Mortality According to Serum 25-Hydroxyvitamin D,” American Journal of Public Health, August 2014, Vol. 104, No. 8, pp. e43-e50. doi: 10.2105/AJPH.2014.302034
