Is it true that you need to have more than 10 cups of coffee a day to have a caffeine addiction?

I am not sure about the exact number but a good way to look at things is how do you feel when you don't have coffee. Do you have extreme headaches that only go away after you have more coffee or more caffeine. I think that could be a better meter.

The amount of caffeine doesn't matter. What matters is the ability to go without it. If you can't go without the caffeine then you have an addiction.

We need to separate addiction from health. It is unhealthy to have more than a few cups of coffee a day (the amount will vary from person to person) but addiction is defined on dependency and this amount is related to the amount that the person needs to have in order to not have withdrawal symptoms or at least to satisfy his or her cravings.

No, that isn't true. You can actually have a caffeine addiction even if you drink only one cup of coffee a day. The test is to go without caffeine and see if you experience any withdrawal symptoms. These symptoms can include headache (the most common symptom), sleepiness, irritability or depression, trouble concentrating, and even flu-like symptoms (nausea, vomiting, muscle pain, stiffness). Caffeine withdrawal starts around 12-24 hours after you stop caffeine and reaches its worst after about one to two days.

If you have more than 10 cups of coffee each day, it seems likely that you'll be one of the 1 in 8 people whose withdrawal symptoms are severe enough to interfere with their ability to perform daily activities. My guess is the 10 cups of coffee theory came from looking at the severity of withdrawal symptoms, but it's actually just a myth and you can be addicted to caffeine even if you consume much smaller amounts.