The vast majority of studies reported inverse associations between 25(OH)D concentration and all-cause mortality .
This association appeared to be non-linear , with progressively lower mortality with increasing 25(OH)D up to a point , beyond which there was no further decrease .
There is moderate evidence that vitamin D status is inversely associated with cancer mortality and death due to respiratory diseases , while for cardiovascular mortality , there is weak evidence of an association in observational studies , which is not supported by the data from intervention or Mendelian r and omization studies .
Epidemiological evidence suggests that vitamin D deficiency is associated with increased mortality , but it is unclear whether this is explained by reverse causation , and if there are specific causes of death for which vitamin D might be important .
The association between serum 25-hydroxyvitamin D3 concentration and risk of disease death in men: modification by magnesium intake
Low vitamin D status increases the risk of death . Magnesium plays an essential role in vitamin D metabolism and low magnesium intake may predispose to vitamin D deficiency and potentiate the health problems . We investigated whether magnesium intake modifies the serum 25(OH)D3 concentration and its associations with mortality in middle-aged and older men . We included 1892 men aged 42–60 years without cardiovascular disease or cancer at baseline in 1984–1989 from the prospect i ve , population -based Kuopio Ischaemic Heart Disease Risk Factor Study .  Serum 25(OH)D3 was measured with the high-performance liquid chromatography using coulometric electrode array detection . Magnesium intake was assessed with 4-day food recording .  Deaths were ascertained by a computer linkage to the national cause of death register . Deaths due accidents and suicides were excluded . Cox proportional hazards regression models were used to analyze the associations . The multivariate-adjusted hazard ratio ( HR ) for death in the lowest ( < 32.1 nmol/L ) versus the highest ( > 49.4 nmol/L ) serum 25(OH)D3 tertile was 1.31 ( 95 % CI 1.07–1.60 , Ptrend = 0.01 ) . Stratified by the magnesium intake , the higher risk was observed only in the lower magnesium intake median ( < 414 mg/day ) ; HR = 1.60 ( 95 % CI 1.19–2.13 , Ptrend = 0.002 ) in the lowest versus the highest 25(OH)D3 tertile , whereas the corresponding HR = 1.07 , 95 % CI 0.75–1.36 , Ptrend = 0.63 ) in the higher magnesium intake median , P for interaction = 0.08 . In this cohort of middle-aged and older men  low serum 25(OH)D3 concentration was associated with increased risk of death mainly in those with lower magnesium intake
The vast majority of studies reported inverse associations between 25(OH)D concentration and all-cause mortality .
This association appeared to be non-linear , with progressively lower mortality with increasing 25(OH)D up to a point , beyond which there was no further decrease .
There is moderate evidence that vitamin D status is inversely associated with cancer mortality and death due to respiratory diseases , while for cardiovascular mortality , there is weak evidence of an association in observational studies , which is not supported by the data from intervention or Mendelian r and omization studies .
Epidemiological evidence suggests that vitamin D deficiency is associated with increased mortality , but it is unclear whether this is explained by reverse causation , and if there are specific causes of death for which vitamin D might be important .