Vitamin D and Calcium May Lower the Risk for Type 2 Diabetes in Women

Vitamin D and calcium intake in relation to type 2 diabetes in women, by A.G. Pittas and colleagues. Diabetes Care 29:650–656, 2006.

What is the problem and what is known about it so far?

A lack of vitamin D and calcium may be linked to getting type 2 diabetes.
Why did the researchers do this particular study?

The researchers wanted to see if there was a link between vitamin D and calcium intake and getting type 2 diabetes.
Who was studied?

More than 80,000 women who took part in the Nurses' Health Study.
How was the study done?

The women regularly received check-ups for a period of 20 years. Every two to four years, the researchers sent questionnaires to the women to figure out how much vitamin D and calcium they consumed.
What did the researchers find?

Over the course of 20 years, over 4,800 women developed type 2 diabetes. The researchers found that a combined intake of over 1,200 milligrams of calcium and over 800 units of vitamin D was linked with a 33% lower risk for type 2 diabetes (as compared to women who took much smaller amounts of calcium and vitamin D). The results show that consuming higher amounts of vitamin D and calcium help lower the risk for type 2 diabetes in women.
What were the limitations of the study?

This study relied on responses to questionnaires to assess vitamin D and calcium intake. Some women may have given inaccurate responses.

Almost all of the women in this study were white. The results of this study may not be the same in other racial or ethnic groups or in men.
What are the implications of the study?

A high intake of vitamin D and calcium was linked with a lower risk of type 2 diabetes in this study. If future studies confirm the results of this study, increasing intake of vitamin D and calcium may be an inexpensive and easy way to help prevent type 2 diabetes.

FOR MORE INFORMATION

Calcium, Vitamin D, and the Metabolic Syndrome in Middle-Aged and Older Women

The Other "C": Getting Your Calcium Diabetes Food and Nutrition Bible