Can a very Low-Carb diet beat standard advice for prediabetes?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * overweight, defined as BMI \>= 25 kg/m2 \>= 23 kg/m2 if of Asian descent * HbA1c between 5.7% - 6.4% verified at baseline * willingness to participate in group-based sessions * able to engage in at least light physical activities such as walking * willingness to follow a prescribed diet, be randomized, self-weight, track diet, and report physical activity minutes * physician approval to participate Exclusion Criteria: * history of type 1 diabetes or type 2 diabetes * use of anti-obesity medications or participation in another weight loss program or intervention * use of glucose lowering medications other than metformin * pregnant or planning to become pregnant during the intervention period * breastfeeding * use of oral corticosteroids * previous bariatric surgery or planning to have bariatric surgery during the study period * blood disorders that influence HbA1c, including frequent blood transfusions, phlebotomy, anemia, hemoglobinopathy, polycythemia * any condition for which the study team deems participation to be unsafe or inappropriate * inability to read, write, or speak English * inability to provide informed consent * adherence to a vegan or vegetarian diet * adherence to a very low-carbohydrate (keto) diet * difficulty chewing or swallowing * no influence over what foods are purchased, prepared, and/or served * above weight limit for DEXA (500 pounds) * untreated eating disorder or mental health conditions, such as depression with suicidal ideation, bipolar or schizophrenia with psychosis * use of warfarin * chronic kidney disease, stage 4 or higher * use of loop diuretics: 20mg or higher of furosemide or equivalent (Lasix (furosemide), Bumex (bumetanide), Ederin or Sodium Edecrin (ethacrynic acid), Demadex or Soaanz (torsemide)) * any concerning values in baseline labs (participants will be referred to Primary Care Physician and will be allowed to return for later enrollment if labs are no longer concerning) * Triglycerides 600 Milligrams per deciliter (mg/dL) or higher * Thyroid stimulating hormone of any abnormal value * Potassium of any abnormal value