Improved Insulin Resistance and Glucose Variability by Super-Low Carbohydrate Diet

*Corresponding author: Hirohisa Urasaki, Hiroshi Bando*, Harumi Kobayashi, Hiroko Urasaki, Hiroko Ogawa, Miwako Nakanishi, Osami Watanabe and Shinji Nagahiro


Diabetes mellitus (DM) has been more prevalent. American Diabetes Association (ADA) proposed the Standards of Medical Care in Diabetes-2022. For nutritional therapy, low carbohydrate diet (LCD) has been recognized for its benefits. Authors have continued diabetic research concerning LCD and meal tolerance test (MTT).
Case Presentation
The case is 61-year-old male with type 2 diabetes mellitus (T2DM) for years. His hemoglobin A1c (HbA1c) increased to 7.8% in autumn 2021, and further evaluation and treatment was conducted including LCD, daily check of meal and carbohydrate amount, 75 g OGTT, glucagon stimulation test (GST) and others.
He was on super-LCD method including 12% of carbohydrate. His carbohydrate intake amount and 45-minutes post-prandial blood glucose showed significant correlation. The results of 75 g OGTT twice in May 2020 and December 2021 showed that similar pattern of glucose and insulin responses and insulinogenic index (IGI). In contrast, they showed decreased fasting immuno-reactive insulin (IRI) and Homeostasis model assessment insulin resistance (HOMA-R). For GST, C-peptide showed normal response.
Discussion and Conclusion
Judging from the results of MTT, OGTT, GST and IGI, he seems to show rather decreased insulin resistance by LCD associated with preserved insulin secretion ability to some degree. Further investigation would be required from pathophysiological point of view.
Super-low carbohydrate diet (LCD); Meal tolerance test (MTT); Type 2 diabetes mellitus (T2DM); Insulinogenic index (IGI); Glucagon stimulation test (GST); Homeostasis model assessment insulin resistance (HOMA-R).