MONDAY, May 14, 2007 (HealthDay News) -- A diet rich in fiber from cereals and in magnesium may help lower the risk of developing type 2 diabetes, German researchers report.
Ann Albright, president-elect for health care and education at the American Diabetes Association, said the suggestion that fiber from cereal might be better than fiber from fruits and vegetables in preventing type 2 diabetes "warrants further investigation. But I don't think we should take away the idea that fruits and vegetables are not important," she added.
As for the nutrient magnesium, "there are a whole lot of challenges around the study of micronutrients," Albright said. "They are difficult to study. I don't think the public health message is that we should go out and up our intake of magnesium."
The mechanism by which magnesium intake might affect the risk of diabetes "is unclear," she said.
Type 2 diabetes, which generally occurs in the adult years as the body loses it ability to metabolize sugar adequately, is a growing problem, due largely to growing obesity rates, the German researchers noted. Estimates suggest that the number of people worldwide with type 2 diabetes may rise from 171 million in 2000 to 370 million by 2030, according to background information in the article. The associated illnesses, death and health-care costs linked to the disease underscore the need for effective preventive measures, the study authors noted.
For the study, conducted by researchers at the German Institute of Human Nutrition Potsdam-Rehbruecke, more than 9,700 men and 15,365 women, 35 to 65 years old, who completed a food questionnaire were then followed for an average of seven years.
The researchers also did a meta-analysis -- or review -- of previous studies about the relationship between fiber or magnesium intake and risk of diabetes.
Dividing people in the study into five groups based on their intake of fiber from cereals, the researchers found that those who ate the most had a 27 percent lower risk of developing type 2 diabetes than those who ate the least. Greater fiber intake from fruits and vegetables was not associated with diabetes risk, the study found.
Participants who consumed the most magnesium had a 23 percent lower risk of developing type 2 diabetes than those who consumed the least. Green vegetables such as spinach are good sources of magnesium, as are nuts like almonds and cashews.
The research did not touch directly on one important lifestyle issue, physical activity, Albright said. Many other studies have shown "strong evidence of physical activity, as it relates to weight loss, in preventing or delaying development of diabetes," she said.
"So, the take-home messages are that people do need to keep their weight in a healthy range," she said. "And fiber intake is a major component of a healthy diet."
The source of the fiber -- fruits, vegetables or cereals -- does not seem to be of major importance, Albright said. "Unfortunately, many people do not get a lot of fiber in their diet," she said.
And many people do not get enough physical activity -- 30 minutes a day, most days of the week, is recommended, Albright said.
The findings were published in the May 14 issue of Archives of Internal Medicine.
For more on controlling diabetes, visit the U.S. National Diabetes Education Program.