Valiant Living Blog

How Long Does Caffeine Stay in Your System?

Written by Valiant Living Recovery on Saturday, May 11th, 2019

It’s pretty common to start drinking a lot more coffee after quitting drugs or alcohol. Studies have shown that people in 12-step programs drink considerably more coffee than the average person. For the most part, this isn’t a big deal. Research now indicates that coffee may protect against heart failure, liver disease, liver cancer, and type II diabetes, all of which are of particular concern for long-term heavy drinkers. Coffee is also a major source of antioxidants. You only start to get health concerns after about the fourth cup, so unless you’re drinking a lot of coffee, there’s probably not an urgent need to cut back.

The biggest problem is that caffeine can disturb sleep. It’s hard to emphasize enough how important sleep is to recovery. Adequate sleep improves your mood and self-control. It lets you think more clearly. Sleep is when your body heals and fights infection. Feeling sleep deprived destroys your concentration and makes your stress skyrocket so that you feel easily overwhelmed. In short, it’s extremely hard to keep your head together if you’re not getting enough quality sleep. Unfortunately, caffeine is often a crutch for dealing with inadequate sleep and the more you consume, the more likely it will disrupt your sleep. If you want to get as much quality sleep as possible, it’s best to let that caffeine level drop as low as possible before bedtime.

Caffeine gets into your system very quickly. When you drink a cup of coffee, almost all of the caffeine gets into your system in less than an hour. How long it stays in your system depends on individual genetic factors. For most people, caffeine has a half life of four to six hours. That means if you have a slower caffeine metabolism and you drink a cup of coffee at 5 p.m. and go to bed at 11, half that caffeine, plus whatever is left over from earlier, is still in your system.

It’s hard to say exactly how much caffeine that is because caffeine content varies considerably, but it’s roughly 100 mg. One way to decide when to quit consuming caffeine is to ask yourself what fraction of a cup of coffee would you drink immediately before bed and work backward. It may take some trial and error to figure out how fast you metabolize caffeine. People often use the heuristic “no caffeine after noon.” If you assume an 11 o’clock bedtime and slow caffeine metabolism, about 75 percent will be gone by bedtime. For faster metabolisms, it will be closer to 88 percent gone. If you haven’t been sleeping well, see if setting a caffeine curfew helps.
