Can a low-fat vegan diet reduce insulin requirement in type 1 diabetes?

Type 1 diabetes is thought to be caused by an autoimmune reaction that destroys the beta cells in the pancreas that make insulin. Insulin is a hormone that helps move glucose (sugar) from the blood into muscle and liver cells to be used as energy. People with type 1 diabetes must take insulin because their body doesn’t produce enough. Some people with type 1 diabetes may also have insulin resistance, which is a condition in which cells don’t respond well to insulin and glucose remains in the blood. Insulin resistance is strongly influenced by dietary fat, which can inhibit glucose from entering the cells. Over time, high blood glucose levels can lead to health complications.

In the 12-week study, 58 adults with type 1 diabetes were randomly assigned to either a low-fat vegan group with no limits on calories or carbohydrates, or a portion-controlled group that reduced daily calorie intake for overweight participants and kept carbohydrate intake stable over time.

The results showed that in the low-fat vegan diet group, insulin requirements decreased by 28% and insulin sensitivity improved by 127% compared to the portion-controlled diet group. This was accompanied by an average weight loss of 11 pounds in the vegan group, while the portion-controlled group saw no significant change. Increased carbohydrate and fibre intake were associated with improved insulin sensitivity. Additionally, the vegan group experienced greater reductions in total cholesterol (32.3 mg/dL) and LDL cholesterol (18.6 mg/dL) compared to the portion-controlled group.

“With the cost of insulin remaining a concern for many, our groundbreaking research shows that a low-fat vegan diet that doesn’t restrict carbs may be the prescription for reducing insulin needs, managing blood sugar levels, and improving heart health in people with type 1 diabetes,” said Hana Kahleova, MD, PhD, the lead author of the study and director of clinical research at the Physicians Committee for Responsible Medicine.

Reference: Hana Kahleova; Tatiana Znayenko-Miller; Karen Smith; Cyrus Khambatta; Robby Barbaro; Macy Sutton; Danielle N. Holtz; Mark Sklar; Desiree Pineda; Richard Holubkov; Neal D. Barnard; Effect of a Dietary Intervention on Insulin Requirements and Glycemic Control in Type 1 Diabetes: A 12-Week Randomized Clinical Trial; Journal: Clinical Diabetes; https://doi.org/10.2337/cd23-0086