Is This the Best Way to Fast? Why Circadian Fasting Might Be the Key

Over the past 15 years, research on fasting has taken off — and the results are impressive. Studies show that narrowing your eating window can improve blood sugar control, increase insulin sensitivity, and support healthy cholesterol levels.²

Most people who try intermittent fasting choose a late eating window, sometimes starting their first meal at 1 or 2 p.m. But this might not be the best approach for your metabolism.

The Power of Circadian Fasting

Circadian fasting shifts your eating window earlier in the day, aligning food intake with your body’s natural biological rhythms. During daylight hours, your body is primed to use energy efficiently — and in the evening, it naturally transitions into repair and recovery mode.

Some studies suggest that consuming the bulk of your calories before 3 p.m. can help you eat fewer total calories, improve dietary quality, and reduce cravings later in the day.³ Conversely, eating heavy meals or snacks after 8 p.m. has been linked to poorer metabolic health outcomes.

When & How Long to Fast

A typical circadian fast lasts 12–14 hours — for example, finishing dinner by 7 p.m. and having your first meal around 7 a.m. Both early and extended fasts have been associated with better health and longevity.

That said, fasting isn’t for everyone, and that’s okay. If you do eat breakfast, aim for nutrient-dense meals rich in protein and fiber earlier in the day. This combination helps you:

• Feel full for longer

• Keep energy levels steady

• Support muscle health

• Stabilize blood sugar

The result? More focus, steady fuel for your workouts, and lasting energy to power through the day.

Key Takeaways for Healthy Eating Timing

• Front-load calories earlier in the day for better metabolic alignment.

• Finish eating earlier to give your body a longer overnight repair window.

• Focus on quality — protein, healthy fats, and fiber-rich whole foods.

Whether you choose a full circadian fast or simply shift your meals earlier, you’ll be working with — not against — your body’s natural rhythm.