Caffeine: My Favorite Nemesis

Editor's note: This article was written by Carin Lefkowitz and originally appeared on our sister site, Insomnia.Sleep-Disorders.net.

I’ve loved coffee my whole life. It’s normal for children to drink coffee in my family’s culture. I vividly recall having a mug every morning alongside my bowl of Cocoa Pebbles as an 8- or 9-year old. Granted, my cup was probably filled with more sugar and milk than coffee in those days, but I developed a taste for it early on (as well as cavities).

Coffee is still a daily indulgence for me. That first sip in the morning is one of my favorite moments of the day and you better not try to talk to me beforehand. Unfortunately, like most people with a history of sleep problems, my relationship with caffeine has become complicated.

Sources of caffeine

One struggle I have is that caffeine seems to be in everything I love. Of course, you know it’s in your coffee and many teas. But did you know that also includes iced teas and decaf coffee (about 97 percent of caffeine is removed)? Many sodas also contain caffeine, as does dark chocolate. And perhaps unsurprisingly, my favorite beers – stouts and porters – are often brewed with coffee beans.

Although I limit myself to 2 cups of coffee in the morning, I can consume a lot of caffeine during the day if I’m not paying attention.

How does caffeine impact sleep?

Caffeine is a drug that can have a lot of indirect effects on sleep. It is a stimulant that impacts many body functions, including increasing your blood pressure and heart rate. Like all stimulants, caffeine may also make some people feel anxious or jittery. All of these kinds of hyperarousal can interfere with sleep.

Caffeine is most known for its ability to make us feel more alert and less tired. That’s because caffeine interferes with our ability to detect sleepiness. That seems like a great benefit after a bad night’s sleep but can become problematic if the caffeine doesn’t wash out of your body before bedtime.

How long does caffeine stay in your body?

When you consume caffeine is as important as how much you consume. Caffeine has a half-life of between 5 to 7 hours, which means it can still have an impact 10 to 14 hours later.

So that soda you drank during your mid-afternoon slump may still be keeping you awake at bedtime.

Caffeine wasn’t always a problem for me

What’s been most frustrating to me is that my sensitivity to caffeine has changed over time. 9-year old me had no problem. And college-aged me regularly enjoyed late-night cappuccinos at Figaro’s Cafe (I was very hip back then).

But once I hit my 30s, drinking caffeine after lunch was like rolling the dice with my sleep. Even drinking a diet Coke after dinner can keep my brain buzzing into the early morning hours.

Turns out that our sensitivity to caffeine can change over time based on age, BMI, and medications we’re taking. It’s clear that either I’ve become more sensitive to caffeine with age and/or it’s taking longer for my body to process it.

If you’ve noticed that your sleep is being impacted by caffeine, it may be helpful to track how much you’re consuming, when you’re consuming it, and whether your sensitivity has changed over time.