The best vitamin to recommend in the scenario given above is VITAMIN B3, WHICH IS ALSO KNOWN AS RIBOFLAVIN. John is suffering from ariboflavinosis, which is a deficiency disease that is due to inadequate intake of riboflavin and the disease is characterized by sores on the mouth.
Being sedentary means you don't move around (stay in one place).
People who are sedentary could play video games at their computer all of the time, which means they stay up late.
Staying up late leads to sleep deprivation.
Thus, video gamers could have sleep deprivation.
