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If you've been told you have Type 2 diabetes, chances are you're trying to control carbohydrates (starches and sugars) through portion sizes and limiting sweets. A new study published this week by the American Diabetes Association, however, suggests managing diabetes doesn't need to involve measuring portions or counting calories -- provided you follow a low-fat, vegan diet.

It seems a low-fat diet that shuns all animal foods does a better job at helping Type 2 diabetics control blood sugar and shed excess pounds than the standard diabetic diet. According to the study results, it's an easier diet to follow.

An estimated two million Canadians have diabetes; by 2010, that's expected to reach three million, due in part to increasing obesity rates and sedentary lifestyles. The vast majority of people with diabetes (90 per cent) have Type 2 diabetes, which occurs when the pancreas does not produce enough insulin (the hormone that clears sugar from the bloodstream), or when the body does not effectively use the insulin that is produced. If the body does not have insulin, or cannot use it properly, the result is a high blood-sugar (glucose) level. Left untreated, or improperly managed, diabetes can lead to serious complications, including heart disease, stroke, kidney disease, blindness and nerve damage.

The goal of diabetes treatment is preventing complications or slow their progression. Management includes regulating blood sugar through diet and exercise, and often, medications. Dietary guidelines endorsed by the Canadian and American diabetes associations include balanced meals, controlling the amount of carbs eaten over the course of the day, limiting added sugars, reducing saturated fat, increasing fibre and maintaining a healthy weight.

In the study, researchers from the Physicians Committee for Responsible Medicine, the George Washington University, and the University of Toronto randomly assigned 99 people with Type 2 diabetes to either a low-fat vegan diet or a standard diabetic diet for 22 weeks. On the low-fat vegan diet, people were asked to avoid all animal products and added fats and oils, and favour low-glycemic carbs. (Foods with a low glycemic index, such as oats, bran cereals, legumes, nuts, apples and oranges, release sugar more slowly into the bloodstream.) Those on the vegan diet did not restrict portion sizes, calories or the amount of carbs consumed.

The standard diabetic diet was calorie-controlled in order to promote weight loss. As such, participants were required to measure foods. Participants in both diet groups attended weekly education sessions led by dietitians, who helped them follow their diet at home and in restaurants.

Both meal plans led to significant improvements, but the low-fat vegan diet outperformed the standard diabetic diet. After 22 weeks, 43 per cent of those on the vegan diet and 26 per cent of those on the standard diabetic diet were able to stop taking blood sugar medications, or lower the dose. Among participants whose diabetes medications remained unchanged, those following a vegan diet achieved better blood-sugar control, as indicated by bigger improvement in a blood test called A1C (glycosylated hemoglobin).

The A1C test gives an average of a person's overall blood sugar level for the past three months. It measures the amount of blood sugar attached to hemoglobin molecules -- the pigment in red blood cells that delivers oxygen to your body. The higher your blood sugar, the more hemoglobin molecules you will have with sugar attached. In Type 2 diabetes, the goal for A1C is 7 per cent or lower (less than 6 per cent is ideal).

People on the vegan diet also lost more weight (6.5 kilograms versus 3.1) and achieved a much greater drop in LDL (bad) cholesterol levels (21.2 per cent versus 10.7 per cent).

Compared to those on the standard diabetic diet, participants on the vegan diet consumed less fat (30 grams versus 52 grams per day), saturated fat (6 grams versus 14) and more fibre (36 grams versus 19). That's not surprising because people in the vegan group avoided all animal foods (sources of cholesterol-raising saturated fat), did not add fats to their meals, and were told to choose low-glycemic foods, such as beans and vegetables (higher in fibre).

The fact that people on the vegan diet could eat as much as they wanted, which increased their daily carb intake, and still experience such favourable blood-sugar and weight-loss results is surprising. (The vegan-diet followers consumed 75 per cent of their daily calories as carbs from fruits, grains, legumes and vegetables.)

Researchers believe a low-fat, plant-based diet can improve how the body uses insulin. Low in fat and high in fibre, vegan diets are typically lower in calories, which can facilitate weight loss, resulting in better blood-sugar control. Low saturated fat and higher fibre content may also affect insulin sensitivity in other ways.

Perhaps the vegan diet worked so well because, in part, it was easier to follow. In the study, compliance to the vegan diet was surprisingly higher, compared to the conventional diabetic diet. The plant-based diet did not require weighing or measuring foods. There was no limit on calories, so participants could eat as much as they wanted until they felt full. (Anyone who's followed a weight loss plan knows feeling hungry is a surefire way to break your diet.) David Jenkins, one of the study's authors and Canadian Research Chair in Metabolism and Nutrition at the University of Toronto and St. Michael's Hospital, says these findings point to a "diabetic portfolio" of foods -- plant foods with a strong impact on diabetes and its complications. His previous studies have revealed a low saturated fat diet that includes soy protein, almonds, and soluble (viscous) fibre to have a powerful cholesterol-lowering effect.

For some people, adopting a plant-based diet requires making big changes at first, changes that may seem overwhelming. Start gradually by replacing three animal-based meals a week with vegetarian protein. Try soy milk on breakfast cereal, tofu in stir-fries, soy ground-round in pasta sauces, or vegetarian (soy-based) deli slices in sandwiches.

Consult your dietitian or doctor before changing your diabetic diet. Never stop taking diabetes medication without checking with your doctor. For more information about Type 2 diabetes, visit http://www.diabetes.ca, the Canadian Diabetes Association website.

Leslie Beck, a Toronto-based dietitian at the Medcan Clinic, is on CTV's Canada AM every Wednesday. Visit her website at lesliebeck.com.

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Sample low-fat vegan menu

Study participants received low-fat vegan menus, such as this one.

Breakfast: oatmeal topped with raisins, banana and soy milk; pumpernickel toast and jam, an orange

Snack: apple

Lunch: vegetable soup; veggie burger on whole-grain bun; fruit cup

Snack: non-fat soy latte

Dinner: miso soup; vegetable stir-fry with low-fat tofu; brown rice, sliced bananas

Source: Neal Barnard, Physicians Committee for Responsible Medicine