A practical step-by-step guide for Type 1 diabetics transitioning to a very low-carb ketogenic diet safely.
Topic
Time-in-Range
TIR (Time in Range) measures the percentage of time your blood sugar stays within a target range, typically 3.9-10.0 mmol/L (70-180 mg/dL) for people with diabetes. It's captured by continuous glucose monitors (CGMs) that track blood sugar every 5 minutes, 24/7. TIR provides a much more complete picture than HbA1c alone, since you can have the same average blood sugar with wildly different patterns—stable versus yo-yoing between highs and lows. The official treatment goal is at least 70% time in range, but only about half of people with diabetes achieve this. Many people following very low-carb or keto diets consistently maintain TIR above 90%, and some even tighten their target range to 3.9-8.0 mmol/L (70-145 mg/dL)—matching non-diabetic levels—and still achieve 75-90% time in range.
Article (1)
Research (2)
Low‑carb, dietitian‑guided eating in type 1 diabetes improved HbA1c, time‑in‑range, and cut insulin—without more hypos or ketoacidosis. Short‑term, promising, needs larger trials.
Therapeutic carbohydrate reduction (low-carb to very low‑carb) in type 1 diabetes can lower blood sugars, reduce insulin needs, and improve A1C—often with fewer highs and lows—when done with proper medical oversight. This comprehensive guide (96 page) available in full text is an excellent paper to bring to your doctor.