Why have I gained weight after drinking more water and being happier?

Is drinking water related to obesity? Why could this happen to me?

In past decade, I worked as university lecturer and also completed PhD at the same time. Most of the time, I sat and worked hard on a ton of electronic files and tangible paper documents, both from my students, my boss, and my doctoral classes. I had only 2-3 day, half an hour a day of each week to exercise outdoor. I ate 2 meals a day and a lot of unhealthy snacks during sitting in office. Many times, the meal was not the real meal. It was like instant noodle and junk food.

Copyrights by the Sw Eden, 2022

During that decade, my weight was about 52 kilograms or about 115 pounds. One of my past bosses said that I looked older than most people with the same age, and also looked older than older friends. I got angry, not because of I am ageist, but because I worked much harder than all of those he mentioned. They assigned me too much work and too many classes to teach when I was PhD student. Some might be jealous and did not want me to complete this degree.

Finally, after long hard road in that decade, I left those jobs, and now I have more time to write books, blogs, make some videos, creates paintings, and also help suggest some people about statistic. I have about 1 hour a day, everyday of the week, to exercise outdoor. I eat real meal with nutrition, 1-2 meals a day. I eat less snack and drink more water. I drank less than 2 liters a day, and now I drink about 3 liters a day.

My weight is increased so fast. I look fatter and younger. My current weight is 62 kilograms or about 137 pounds. I think I am too heavy because my feet get hurt. So, my question is, can I get fat from drinking more water and being happier?