Patients with higher levels of vitamin D had a lower incidence of diabetes, according to a long-term study recently published in PLOS One.
The study examined the effects of vitamin D in 903 healthy adults followed since the late 1990s. Researchers found that those who had lower amounts of vitamin D in their blood were more likely to later develop type 2 diabetes.
After following patients through 2009, researchers determined that patients with 25-hydroxyvitamin D concentrations that were at least 30 ng/ml had an incidence of type 2 diabetes one-third the incidence of those below that figure.
Garland said the results were even stronger for patients with 25-hydroxyvitamin D concentrations of at least 50 ng/ml. These patients had an incidence of diabetes one-fifth that of those below this amount.
Garland believes to achieve 25-hydroxyvitmin D concentrations this high, individuals need to take about 4,000 international units of vitamin D3 each day. While vitamin D3 can be increased by exposure to sunlight or by consuming certain foods, Garland said supplements should have the same effect.