Coffee and studying go together like Koa and a pink highlighter. But does that extra cup actually help you learn, or does it just make you jittery at 2 a.m.? We looked at what the research says, so you can sip smarter this semester.
How much caffeine is "okay"?
The European Food Safety Authority (EFSA) concluded in 2015 that, for healthy adults, single doses of up to 200 mg of caffeine (about two and a half espressos) and up to 400 mg spread over a day do not raise safety concerns. For pregnant women, EFSA puts the limit at 200 mg a day, and for children and teens it suggests a conservative level of about 3 mg per kg of body weight. Energy drinks, cola, tea and chocolate all count too.
Timing matters more than you think
A 2013 study in the Journal of Clinical Sleep Medicine (Drake and colleagues) gave healthy sleepers 400 mg of caffeine at bedtime, three hours before bed or six hours before bed. Even the six-hour dose cut total sleep by more than an hour, and the participants didn't notice. Since sleep is when your brain consolidates what you studied, a late-afternoon coffee can quietly undo the work you just did.
Koa's tip: make your last caffeinated drink of the day at least six hours before you plan to sleep.
Can coffee help you remember?
Maybe a little, in a very specific way. In a 2014 study in Nature Neuroscience, researchers at Johns Hopkins (led by Daniel Borota, with Michael Yassa) gave people who rarely drink caffeine a 200 mg tablet after they studied a set of pictures. A day later, the caffeine group was better at telling the original pictures apart from very similar ones. It's one study with non-regular drinkers, so it's not a magic memory pill, but it's a fun reason to enjoy your coffee after a study block rather than only before.
The "coffee nap"
Caffeine usually needs around 15 to 20 minutes to kick in. The Sleep Foundation describes the "coffee nap": drink a coffee, then nap for about 20 minutes, and wake up just as the caffeine starts working. Keep it under 30 minutes to avoid that groggy feeling. Studies with drivers and shift workers found the combo boosted alertness more than either one alone.
A simple coffee + study routine
- Have your coffee early in the day and start a focus session while it kicks in.
- Work in Pomodoros: 25 minutes of focus, 5 minutes of break. Try the free Koa study timer on pinkoa.com.
- Use breaks for water, not refills. Hydration helps you feel less tired too.
- Stop caffeine six hours before bed and protect your sleep.
Sip with Koa
New today: the Koa Hearts Stainless Steel Tumbler 20oz, with lid and straw, for iced lattes in the library.
Also new: the PINKOA Study Hard Club Spiral Notebook (blank, dot grid, lined or task pages) and the cosy Koa Believes in You Hoodie.
Team hot coffee? The Fueled by Coffee & Cramming mug says it all.
Launch week bonus: use code KOA20 for 20% off everything until Sunday, 4 October.
Shade of the day: Cotton Candy #FFBCD9
Today's pink is Cotton Candy, a soft, sugary pastel. It pairs beautifully with lilac, mint and a pop of orange. Use it as the highlighter colour for definitions in your notes, as a planner header, or with a mint scrunchie and a lilac cardigan for a sweet study outfit.