People with Type 2 diabetes are advised to limit carbohydrates because of worries these foods could overtax the body’s dwindling insulin production and lessen its ability to process glucose. Now some scientists are asking if a diet rich in healthful carbohydrates -- whole grains, beans, fruit and vegetables -- and with just 10% of calories as fat might be another option.
The idea borrows a lesson from heart disease research, which has shown that very strict vegetarian diets quite low in fat and very high in carbohydrates can help reverse blockages -- if people stick with them.
“A diet can be wonderful for you, but if it can’t be practically applied, it can’t do much,” says Robert Eckel, president of the American Heart Assn.
In May, Dr. Dean Ornish, a proponent of the very-low-fat approach for reversing heart disease, reported that this regimen helped people afflicted with both diabetes and heart disease. Not only did they lose weight, but their blood cholesterol improved and they didn’t show a rise in unhealthy fats known as triglycerides, as some researchers feared. Another key finding: Twenty percent of participants who stuck with the diet for a year were either able to cut their insulin and other glucose-lowering medication or eliminate it.
Similar results were reported from a National Institutes of Health-funded study headed by David Jenkins of the University of Toronto and Neal Barnard of the Physicians Committee for Responsible Medicine, a pro-vegetarian group. The four-month trial studied 99 people with Type 2 diabetes. Some were asked to follow the standard dietary advice from the American Diabetes Assn. The others were asked to adhere to a very strict, low-fat vegan diet, devoid of meat, fish, eggs, dairy or any other animal products.
Both groups improved blood sugar control and LDL cholesterol levels. Both lost weight, but the vegan group shed an average of 15 pounds compared with 6 pounds for the group that adhered to the ADA guidelines. Like the Ornish study, the vegan group showed no harmful changes in either triglyceride levels or in high-density lipoprotein (HDL), a protective form of cholesterol. Results of the study were published in the August issue of the journal Diabetes Care.
The findings offer more evidence that eating a very-low-fat regimen with a lot of healthful carbohydrates may not be as harmful as once thought for those with Type 2 diabetes and could prove to be another treatment option.
HDL and triglycerides “are often windows of concern, and they were not modified adversely by this,” says the heart association’s Eckel. “If this more radical approach in diabetes can be tolerated better long term, then we may be on to something here.”
Learning to go vegan takes effort, time and some sacrifice, as Vance Warren, 36, a retired Washington, D.C., police officer found. “I know the difference between a Morton’s steak and a tofu steak,” says Warren, who lost more than 70 pounds while participating in the study and was able to reduce the medication he takes to control his blood sugar. “It’s like the difference between a Mercedes and a Toyota. The hardest thing for me was giving up the chicken wings ... but I really don’t miss them now.”
Experts caution that the findings are not likely to change current recommendations for diabetes until much more research is conducted with larger groups of people. “It’s great that the low-fat vegan diet improved glycemic [blood sugar] control,” says Karmeen Kulkarni, president of health care and education for the American Diabetes Assn. “But we had 50 people here. We have to see if this is palatable in a bigger scheme of things on an ongoing basis.”
In the meantime, there’s wide agreement about how to control or prevent diabetes, as well as heart disease and many types of cancer:
* Eat more plant-based foods. The more varied, the better.
* Easy on the fat. Gram for gram, it contains more than twice the calories as protein or carbs. Being overweight or obese are major risk factors for diabetes, heart disease and some types of cancer. Whatever fat you eat, make it healthy. Reach for fish (not fried), healthy oil such as canola or olive oil, nuts, avocados and seeds.
* Get active. The Diabetes Prevention Program, a large federally funded study of people who are just a step shy of developing diabetes, found that daily exercise (walking is fine) was important to prevent diabetes. How much? Thirty minutes daily. But that half-hour can be broken down into 10-minute increments.