Eating patterns similar to the Mediterranean diet and the blood pressure-lowering DASH may help older women with Type 2 diabetes ward off heart attacks, strokes and related problems, new research suggests.
Diabetes afflicts one-quarter of Americans 65 and older. An estimated 68% of these patients will die of heart disease, and 16% will die of stroke.
The new study focused on data from the Women's Health Initiative, a massive long-term project exploring disease prevention in postmenopausal women. It included more than 5,800 women who developed diabetes as adults but reported no cardiovascular disease at the project's outset. The researchers scored detailed food questionnaires from the women according to how closely their responses fit each of four dietary patterns.
Three patterns – an "alternate" Mediterranean diet, adapted for Western tastes; the Dietary Approach to Stop Hypertension, or DASH; and American Diabetes Association recommendations – all advocate eating more fruit, vegetables, nuts and seeds, legumes, whole grains and some dairy, and less added sugars and red and processed meat. The fourth pattern, a Paleolithic-style diet, emphasizes meat, fruit, nuts, greens and other vegetables, and discourages consumption of grains, dairy, added sugars and alcohol.
The researchers tracked new cardiovascular disease in the women over an average of 12.4 years. About 11% developed heart disease, and more than 6% had a stroke.
Women whose scores were among the highest for the DASH diet were 31% less likely to develop cardiovascular problems than those with the lowest scores, the study found. Those with the highest scores for the ADA guidance and the Mediterranean-style diet had 29% and 23% lower risk, respectively.
The study, published Thursday in the Journal of the American Heart Association, found no link between a high paleo score and a risk that was either lower or higher.
Research is scarce about diet and heart health in people with Type 2 diabetes, said senior study author Andrew Odegaard, because food recommendations for these patients are based largely on information from populations without diabetes.
"These findings support current dietary-related clinical practice recommendations for populations with Type 2 diabetes as being one approach to improve cardiovascular risk," said Odegaard, assistant professor of epidemiology at the University of California, Irvine.
The researchers "do not see any reason why these results would not be applicable to other populations with Type 2 diabetes."
For people in general, diets should include more vegetables, fruits, legumes, nuts, whole grains, lean protein and fish, with less saturated fat, cholesterol and sodium, according to guidelines from the American College of Cardiology and American Heart Association. The guidelines also advise people to minimize trans fats, processed meat, refined carbohydrates and sweetened drinks.
Nurse practitioner Cindy Lamendola, who was not part of the research team, believes the study is a helpful addition to the body of evidence about diet in Type 2 diabetes.
"With all the dietary fads the public is exposed to, findings like those in this study should be reassuring to the public and also an important message to share with postmenopausal women with Type 2 diabetes," said Lamendola, clinical research nurse coordinator at Stanford University in California.
She and Odegaard said ideally, future research would randomly assign people to different diets and follow them for years.
Lamendola, whose research focuses on cardiovascular disease and diabetes, said expanding the number of subjects who are minorities and perhaps including people with conditions like prediabetes also could be revealing.
For people with Type 2 diabetes, Odegaard said key dietary questions relate to the amount and type of carbohydrates – nutrients that patients track closely to control blood sugar.
"The crux of the matter is that nutrition research in humans is hard, messy and difficult to garner funding to carry out," he said. "We'd love to do a rigorous trial of different patterns, including variations on carbohydrate amount and content, in this population."
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