It is good for my health to drink coffee 10 times a day? I am working on a computer 15 hours a day, and I feel tired and sleepy a lot between the work. So I prefer to drink coffee to get rid of tiredness. Coffee gives me an energy boost and makes me able to focus on work. And if I don't drink coffee then I can't do the work properly and makes me very sick. It's not like an addiction but I need something that keeps me focused and coffee does that. So what should I do, I should stop drinking that much coffee or should continue drinking daily. It is safe and good for my body to drink coffee 10 times a day?
Caffeine content of coffee varies widely depending on many factors. How much caffeine does your 10 cups contain? And how much is too much? The Mayo Clinic website has addressed exactly what you are concerned about in their detailed article which can be read here:

https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/caffeine/art-20045678

Important extracts:


  How much is too much?
  Up to 400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults. That's roughly the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two "energy shot" drinks. Keep in mind that the actual caffeine content in beverages varies widely, especially among energy drinks.
  
  [...]
  
  You may want to cut back if you're drinking more than 4 cups of caffeinated coffee a day (or the equivalent) and you're experiencing side effects such as:
  
  Migraine headache
  
  Insomnia
  
  Nervousness
  
  Irritability
  
  Restlessness
  
  Frequent urination or inability to control urination
  
  Stomach upset
  
  Fast heartbeat
  
  Muscle tremors
  
  [...]
  
  Most adults need seven to eight hours of sleep each night. But caffeine, even in the afternoon, can interfere with this much-needed sleep.
  
  Chronically losing sleep — whether it's from work, travel, stress or too much caffeine — results in sleep deprivation. Sleep loss is cumulative, and even small nightly decreases can add up and disturb your daytime alertness and performance.
  
  Using caffeine to mask sleep deprivation can create an unwelcome cycle. For example, you may drink caffeinated beverages because you have trouble staying awake during the day. But the caffeine keeps you from falling asleep at night, shortening the length of time you sleep.


That's also my personal experience as a long-time coffee 'addict', though I am also very sensitive to caffeine and therefore I can tolerate just 2 cups a day before I lose sleep and begin to experience strong physical effects. The key thing is to make sure you don't experience symptoms of caffeine excess, and that you get adequate sleep every day, which also varies from person to person. 

If you feel the need to reduce your coffee intake, the same article linked above provides some useful guidelines.