The vegan meal plan got about 15% of calories from protein, 10% from fat, and 75% from carbohydrate. Participants were told to eat vegetables, fruits, whole grains, and legumes; to favor foods with a low glycemic index (meaning they raise blood glucose levels slowly and moderately); and to avoid animal products and added fats. Portion sizes, calorie intake, and carbohydrate intake were not limited.
The ADA meal plan got 15% to 20% of calories from protein, less than 7% from saturated fat, 60% to 70% from carbohydrate and monounsaturated fat, and no more than 200 milligrams of cholesterol per day. Each person’s recommended meal plan was individualized based on body weight and blood lipid (cholesterol and triglyceride) levels, and all but three participants in this group were prescribed a calorie intake level intended to help them lose weight.
At the end of 22 weeks, both groups had improvements in blood glucose and blood lipid control. However, 43% of the vegan group were able to reduce their diabetes medication, compared to 26% of the ADA group. In addition, hemoglobin A1C (HbA1c), a measure of blood glucose control over 2–3 months, decreased by 0.96 percentage points in the vegan group and by 0.56 percentage points in the ADA group, bringing both groups closer to the ADA goal of an HbA1c level below 7%. The vegan group also lost an average of about 13 pounds, while the ADA group lost an average of 9 pounds.
Not only were the health benefits of following a vegan meal plan apparent, but participants in the vegan group found it a highly acceptable way of eating. A newer report related to an extension of this study showed that the benefits of following a vegan meal plan continued beyond a year, making it the longest research trial to date showing the benefits of following a vegan meal plan in the treatment of Type 2 diabetes.
Making the switch
Because switching to a vegetarian meal plan can lead to weight loss and lower blood glucose and cholesterol levels, your medication needs could change if you make this switch. That means it’s a good idea to speak with your health-care provider before beginning a vegetarian meal plan. People who use insulin may want to review how to adjust their premeal and basal insulin doses and how to prevent and treat hypoglycemia (low blood glucose). Some oral medicines can also cause hypoglycemia and may need to be reduced or discontinued if low blood glucose is occurring frequently. Oral medicines that can cause hypoglycemia include glyburide, glimepiride, glipizide, repaglinide (brand name Prandin), and nateglinide (Starlix).
A registered dietitian can help you create a meal plan that provides necessary nutrients, as well as advise you on whether to take supplements such as vitamin B12, iron, or vitamin D. While the participants in the low-fat, vegan diet study described earlier lost weight and saw improved blood glucose control without restricting portion sizes or counting calories, if you do not see the health benefits you desire after changing your eating habits, you may need to reduce your food intake.
When initiating any new meal plan, including a vegetarian one, it’s a good idea to monitor your blood glucose level more frequently. Checking your blood glucose level before and two hours after a meal will show you how your food choices are affecting it. If your new meal plan leads to weight loss, you may see lower blood glucose levels over time. Keeping a food and blood glucose log when starting a vegetarian meal plan will help you and your health-care providers both tailor your food choices and determine how to adjust the doses of any medicines you are taking.
Some people prefer to change their eating habits all at once, while others prefer to make gradual changes, eating several vegetarian meals a week at first. Whichever approach you choose to take, here are some tips for getting started on a vegetarian meal plan.