I used to be a hardcore gamer. Playing Halo in a lan all night with my friends or going into matchmaking until dawn. It was great, then we all became 21. Instead of energy drinks, we were able consume other refreshments.
The point is, lack of sleep, sitting around and poor nutrition is unhealthy.
I'm not stating that you should stop playing games.
Drink water everyday and find some time to be active outside in the sunlight. Especially if you play games more than 4 hours a day.
Stay hydrated and stay healthy.