Low-carbohydrate, high-fat enteral formulas for managing glycemic control in patients who are critically ill: A review of the evidence

Hyperglycemia is associated with increased morbidity and mortality. Low-carbohydrate, high-fat (LCHF) enteral formulas are marketed to improve glycemic control; however, given the multifactorial mechanisms contributing to hyperglycemia in patients who are critically ill, the effect that LCHF formulas may have on improving glycemic control in this patient population is unclear. Current guidelines for the use of LCHF formulas among patients who are critically ill are limited by a lack of evidence. This review explores recent research published in the past 7 years to determine whether LCHF enteral formulas improve glycemic control compared with standard enteral formulas in patients who are critically ill. Four randomized controlled trials met the inclusion criteria for this review. Their results suggest that LCHF formulas may improve glycemic control in patients who are critically ill with diabetes mellitus and/or who are hyperglycemic. Further large-scale randomized controlled trials are warranted to validate these findings among different subgroups of patients with critical illness. The potential benefits of LCHF formulas need to be weighed against specific limitations, including that LCHF formulas typically do not contain sufficient protein to meet the recommended needs of patients who are critically ill.