Circadian rhythms of the body and their importance - Concepts from the Circadian Code by Dr. Satchin Panda

1. Most of the body functions follow a circadian rhythm and having good rhythm is important for optimal functioning of the body. Disruption of the rhythm can cause lifestyle diseases like obesity, diabetes to other diseases like depression or cancer.

2. Each organ of the body has different clocks and are set by different things. For e.g. the master clock is set by melanopsin produced by the eyes when bright light is seen whereas the gut clock is set by the food we eat.

3. Our body processes are circadian. so the gut digests food for some time and during the downtime it repairs the gut, gets ready with some hormones. So to keep the gut in the best condition, do time restricted eating i.e to eat only within 8-10 hrs during the day. The gut motility is high in the day and less during the night. Once the first food bite is taken, the stomach is active for 8-10 hours. After that it becomes slower, so it is better to not eat after that. The body's fat saving mechanism is active when there is food. If we keep eating the whole day, there is no chance for the body's fat burning mechanism to be active. This way the blood sugar levels are always high and there is no chance for fat burning. This causes diabetes.

4. We sleep with different cycles drowsiness, light sleep and deep sleep. Each day we need to get two to three cycles of the whole sleep cycle. Each part of the cycle different things happen like consolidation of memories, cleaning of impurities in brain and production of new neural connections. So it is important we get good sleep. The biggest disruptor for sleep are blue light and screens. best avoid blue light during sleep and also keep screens away. Give good sleep opportunity of 9 hrs. If you have sleep debt try to take a nap as it will help you clear the sleep debt. When we didn't sleep well, the inflammation in the body is not reduced. so if we wake up with stiff joins then it means we didn't sleep well. If we have sleep apnea we can take a CPAP machine to make sure we sleep well. Try not to get up during sleep by keeping water at the bed side so that we don't need to wake up.

5. There is a best time to take medicine as all the drug targets are circadian. It is best to do cardiac exercise in the morning and resistance training during the day when the muscle tone is high.

6. The gut microbiome also has a circadian rhythm. Maintain good microbiome by eating probiotics

7. We are most attentive in the mornings so it is better to the most challenging work in the mornings. Brighter office has better sunlight and helps us feel active. Caffeine can improve alertness but doesn't reduce your sleep debt, so it will not keep you healthy.

8. IBS, GERD and gas could be casued by circadian disruption.

9. Circadian rhythms control the immune response also at the cellular level. So there are best times for getting surgery and best time for taking medicines also. NSAIDs perform better in the evening.


Regular sleep ( 8 hrs) + TRE ( 8-10 hrs) + exercise = Best health.