Vegan diet benefits people with type 1 diabetes

A low-fat vegan diet rich in fruits, vegetables, grains and legumes reduces insulin requirements and improves insulin sensitivity and glycemic control in people with type 1 diabetes, according to a first-of-its-kind study. The study also found that a vegan diet led to improvements in cholesterol levels, kidney function and weight.

It type 1 diabetes is thought to be caused by an autoimmune reaction that destroys the beta cells in the pancreas that produce insulin. Insulin is a hormone that helps transport glucose (sugar) from the blood to muscle and liver cells for use as energy. People with type 1 diabetes must take insulin because their bodies do not make enough of it. Some people with type 1 diabetes may also have insulin resistance, a condition in which cells do not respond well to insulin and glucose stays in the blood. Insulin resistance is strongly influenced by dietary fats, which can prevent glucose from entering the cells. Over time, high blood glucose levels can lead to health complications.

In the 12-week study, which is the first randomized clinical trial to examine a vegan diet in people with type 1 diabetes, 58 adults with type 1 diabetes were randomly assigned to either a low-fat vegan group with no calorie restrictions, or to a low-fat vegan group with no calorie or carbohydrate restrictions, or a portion-controlled group that reduced daily calorie intake for overweight participants and kept carbohydrate intake stable over time.

Those who followed a low-fat vegan diet reduced the amount of insulin they needed to take by 28% and increased insulin sensitivity (how well the body responds to insulin) by 127% compared to those who followed a portion-controlled diet. This was associated with changes in body weight. Body weight decreased by an average of about 5 pounds in the vegan group compared to little change in body weight in the portion-controlled group. Changes in insulin sensitivity were also associated with increased carbohydrate and fiber intake.

Total cholesterol levels decreased by 32.3 mg/dL in the vegan group compared to 10.9 mg/dL in the controlled portion group. LDL cholesterol decreased by about 18.6 mg/dL in the vegan group and did not change significantly in the controlled portion group.

Type 1 diabetes is associated with an increased risk of cardiovascular disease and death. In this study, reduced insulin use on a vegan diet corresponds to a 9% reduction in cardiovascular disease risk; lower HbA1c corresponds to a 12% and 8.8-12% reduction in heart attack and cardiovascular disease risk, respectively; and lower LDL cholesterol corresponds to an approximately 20% reduction in the risk of major cardiac events, including heart attack and stroke.

Approximately 40,000 new cases of type 1 diabetes are diagnosed each year. According to recent analyses, the prevalence of type 1 diabetes will increase by 107% by 2040. The annual cost of treating type 1 diabetes has increased by more than 50% compared to 2012 and 2016, primarily due to rising prices for insulin and diabetes monitoring equipment.

As the cost of insulin remains an issue for many, our groundbreaking study shows that a low-fat, vegan diet with no carbohydrate restriction may be a prescription for reducing insulin requirements, controlling blood sugar levels, and improving heart health in people with insulin-dependent type. 1 diabetes." - said Hana Kaleova, M.D., Ph.D., lead author of the study and director of clinical research for the Physicians Committee.

The study authors say larger trials are needed to confirm these findings.

Thestudy is published in the journal Clinical Diabetes.