NEW YORK (Reuters Health) – A diet filled with plenty of whole grains, fruits and vegetables, and low-fat dairy may help people lower their risk of type 2 diabetes, regardless of their race or ethnicity, a new study suggests.

On the other hand, researchers found, a diet high in red meat, high-fat dairy and refined grains may boost the odds of diabetes development.

Type 2 diabetes is closely linked to obesity and it’s known that maintaining a healthy weight through diet and exercise reduces the risk of developing the disease. There is also evidence that diet affects diabetes risk independent of a person’s weight.

The new findings, reported in the medical journal Diabetes Care, highlight the importance of the whole diet — rather than focusing on certain foods or food groups that might be beneficial.

They also suggest that a healthy diet has equal benefits for racial and ethnic groups that are particularly at risk of type 2 diabetes, including African- and Hispanic-Americans.

The researchers, led by Dr. Jennifer A. Nettleton of the University of Texas Health Sciences Center in Houston, based their findings on 5,011 U.S. adults taking part in a long-term heart-health study. The study included white, Hispanic, black and Chinese-American men and women between the ages of 45 and 84.

Overall, the researchers found that people whose diets were highest in whole grains, fruits, nuts, low-fat dairy and vegetables — particularly leafy greens — were 15 percent less likely to develop type 2 diabetes over 5 years than those who ate the lowest amounts of these foods.

In contrast, adults whose diets were high in red meat, high-fat dairy, refined grains like white bread, plus beans and tomatoes, saw their diabetes risk go up by 18 percent as a group.

Beans and tomatoes are nutrient-rich foods, Nettleton’s team points out, and their link to diabetes here probably reflects the fact that many people eat them as part of a less-than-healthy diet — one that favors pizza and tacos, for instance.

The findings, the researchers conclude, “underscore the importance of the collective influence of multiple food groups in the development of type 2 diabetes.”

SOURCE: Diabetes Care, September 2008.