Diabetes Studies Update on Nutrition, and on Cancer

Adding lentil soup and pasta to your diet may be the way to go if you have type 2 diabetes, based on a new study about the benefits of low-glycemic foods.

The new study found that a diet of "low-glycemic foods" - such as beans, nuts, peas, lentils, and pasta - was better than a high-cereal-fiber diet, particularly when it comes to lowering blood sugar and other risk factors for heart disease in people with diabetes.

"These findings fit with the general tenor of what's gone before,” says study author Dr. David J.A. Jenkins, at the University of Toronto.

“The trouble is that those studies tended to be considerably smaller and for shorter periods of time, and they didn't always show the effects significantly," he says. "I think this certainly supports a recommendation to people that this is an extra tool in the tool kit."

Dr. Suzanne Steinbaum, at Lenox Hill Hospital in New York City, says, "This reemphasizes what we know - at the end of the day, the best diet is the Mediterranean-type diet: nuts, beans, lentils, fruits, vegetables. The study didn't exactly call it a Mediterranean diet, but the components of it were Mediterranean."

Cancer Plus Diabetes Adds Risks

A second study found that people who have type 2 diabetes when they are diagnosed with cancer face a greater risk of death compared to cancer patients without diabetes.

Both papers were published in the Journal of the American Medical Association.

The diabetes epidemic now affects some 20 million people in the US alone, representing 7 percent of the population. Having diabetes increases the risk for heart disease, cancer, and other health problems.

Although many drugs are available to control blood sugar levels, the evidence on how well they reduce the risk of cardiovascular problems is not entirely clear. This makes a proper diet crucial to help control the disease.

For the new study, researchers at St. Michael's Hospital and the University of Toronto randomly selected more than 200 people with type 2 diabetes to follow either a high-cereal-fiber or a low-glycemic-index diet for six months.

All the participants were already taking blood-sugar-lowering medications.

Carbohydrates in a low-glycemic-index diet are absorbed through the small intestine and are converted to blood sugar at a slower rate when compared with higher glycemic foods according to researchers. This means that the blood sugar is more stable.

Further, study results showed a 0.5 percent decrease in hemoglobin A1c (HbA1c) levels, a longer-term measure of blood sugar levels, in people on the low-glycemic-index diet. This is compared with a decrease of only 0.18 percent in the alternate group.

Insulin and Breast and Colorectal Cancers

Those in the low-glycemic group also saw an increase in their high-density lipoprotein (HDL), or "good" cholesterol of 1.7 mg/dL, compared to an HDL decrease of 0.2 mg/dL in the high-cereal-fiber group.

While the reduction in HbA1c levels was small, the study authors suggest that this might result in a 10 to 12 percent reduction in cardiovascular complications based on previous studies.

For the second paper in the journal, researchers at Johns Hopkins University pooled data from 23 completed studies and found that people with diabetes were 41 percent more likely to die of cancer than people who did not have diabetes.

Specifically, there was a 76 percent increase in the risk of death from endometrial cancer, a 61 percent increase for breast cancer, and a 32 percent increase for colorectal cancer.

The researchers say possible explanations for this increased risk could result from an insulin environment that contributes to tumor cell proliferation, less-rigorous screening practices, or complications from diabetes. These factors may somehow play a role in cancer treatment decisions.

Always consult your physician for more information.