Effectiveness of carbohydrate diet restriction in type 2 diabetes mellitus on insulin and incretin-based therapies

Abstract

Type 2 diabetes mellitus (T2DM) is the most common form of DM characterized by variable degrees of hyperglycemia, insulin
resistance, and impaired insulin secretion. Insulin resistance and progressive failure of pancreatic β-cells reduce insulin secretion
and consequently increase blood glucose and free fatty acid levels. The deterioration of pancreatic β-cell function in T2DM leads
to therapeutic failure of oral agents over time. Hence, the most T2DM patients ultimately require insulin therapy, which may cause
hypoglycemia. Regular carbohydrate intake with respect to time and amount reduces the risk for hypoglycemia in DM patients
on fixed daily insulin doses. In T2DM, obesity aggravates the metabolic abnormalities such as hyperglycemia, dyslipidemia, and
hypertension. Weight loss and exercise improve insulin resistance, glycemic control, and reduce risk factors in overweight and
obese T2DM patients. Low caloric but healthful eating pattern promotes weight loss in overweight or obese T2DM adult patients.
Incretins are released after ingestion of a meal augment the secretion of insulin and this account for the greater insulin response to
oral glucose than to intravenous glucose. Incretin-based therapies along with reduced insulin doses sustain glycemic control without
an increase in hypoglycemia or weight gain. The low-carbohydrate diets in T2DM patients on insulin and incretin-based therapies
could increase the likelihood of hypoglycemia. Hence, as prevention of hypoglycemia is an essential part in the management of
DM, the individualized dietary plan or eating pattern and adjustment of insulin and incretin doses should be considered for each
patient based on his or her glycemic control.