Extended fasting doesn’t just change your weight - it transforms your biomarkers. Over 10 months, my 9- and 10-day water fasts improved 8 out of 10 InsideTracker biomarker categories, especially Heart Health, Metabolism, and Inflammation. See how fasting biomarkers like ApoB, glucose, triglycerides, and hsCRP shifted before, during, and after fasting - and why proper refeeding makes all the difference.

How fast do ketones rise during fasting? In my 7-, 9-, and 10-day water fasts, I tracked how quickly I entered ketosis and what made the biggest difference. Turns out, movement early in the fast helps you reach deep ketosis faster — and burn more fat along the way. Here’s how glucose drops, ketones rise, and why fasting ketosis is totally different from dangerous ketoacidosis.

Intermittent fasting for weight loss isn’t a trend — it’s a proven way to train your body to burn fat efficiently, stabilize energy, and improve long-term health. Learn how it works, how to start, and what science really says about the fastest and safest path to sustainable fat loss.