Few things that I don't love about traveling- delays, turbulence, take offs and landings. But jet lag is worst as it takes the longest time to fix itself.
Our bodies are wired with a natural 24 hour biological clock, otherwise known as the circadian rhythm. In more simple terms, our body clock is driven by an internal time keeping system which is influenced by light-dark cycle of night and day. This clock regulates our daily activities such as sleeping, waking, and eating along with body temperature regulation.
Any alteration to this body clock when you travel from west to east (or vice versa) on the globe on a high speed aircraft can cause circadian dysrhythmia or desynchronosis or simply a jet lag.
Researchers have linked this disruption to two groups of neurons at the base of the hypothalamus, located in the brain. One group is synchronized with deep sleep which results from physical fatigue. The second group controls the dream state of rapid eye movement, also known as REM sleep. Hopping a few time zones can mess up this system. Since I was traveling east I fast forwarded my life by about 10 hours, crossing nine time zones.
But what is a time zone?
Noon is the time when the sun is at its highest in the sky. Since the Earth rotates at the rate of 15 degrees every hour, The sun is at its highest point in the sky at different times throughout the day for different countries around the globe. Hence, we divide the world into 24 equal slices or zones, 15 degrees each, and adjust the clocks accordingly for each zone. The Greenwich Meridian in England is used as a starting point to determine time, so you can say it is "zone zero". As you move East, the clock moves forward, which results in a loss of time.
So from Boston to Amsterdam, the time difference is "minus five hours".
From Amsterdam to New Delhi another 5 hours are lost.
A total 10 hours got fast forwarded in my life.
Interesting fact: you do not experience jetlag when you fly north to south or vice versa even on a long haul flights because you stay in the same time zone.
For globe trotting there is an app called Jetlag Genie and Jetlag Rescue that makes things easy by creating a schedule of when you should eat, sleep, and nap in order to adjust to new time zone.