What is the Dr. Boz Ratio?
The Dr. Boz Ratio (DBR) divides fasting blood glucose (mg/dL) by blood ketones (mmol/L). It is a single number that reflects whether you are primarily burning glucose or fat.
Dr. Annette Bosworth (Dr. Boz) uses it to help patients see insulin resistance in real time — especially when scale weight stalls but metabolic health is changing.
How to calculate it
You need a meter that reads both glucose and ketones from a finger stick. Measure in a fasted state — morning before food is common.
Formula: Dr. Boz Ratio = Glucose (mg/dL) ÷ Ketones (mmol/L). Example: 90 mg/dL ÷ 1.5 mmol/L = 60.
Our fasting clock includes optional fields to track your ratio during active fasts.
How to interpret your number
Dr. Boz emphasizes: "Ketones rise first, glucose falls second." Do not expect instant ratio improvements on day one of low carb.
- Above 80: Still glucose-dominant. Tighten carbs, consider longer overnight fasts, or improve fat intake quality.
- 40–80: Moderate ketosis. Good for general health and steady weight management.
- Below 40: Deeper ketosis associated with autophagy and therapeutic benefits — approach gradually.