If you’ve spent more time with a buzz-inducing cup of coffee than you have with your best friend this week, you’re not alone. The Coffee Association of Canada’s 2017 study found that coffee is the most popular beverage among Canadians over 16. In a recent Student Health 101 survey, more than 70 percent of students across Canada say they have at least one coffee or caffeinated drink a day. And it’s not just the joe. Caffeine is everywhere—in tea, pop, energy drinks, and even some types of gum and chocolate.
“Caffeine, in any of its forms, is a legal stimulant,” says Dr. Pierre-Paul Tellier, Family Physician at the CLCS de Côte-des-Neiges at McGill University in Quebec. That means it temporarily increases energy and alertness. People who drink caffeine very regularly (e.g., daily or multiple times a day) may become “dependent” on it, meaning they need more of it to get the same results and they may suffer mild withdrawal symptoms (e.g., headaches, irritability) if they stop, according to a 2013 review of the literature published in the Journal of Caffeine Research.
Caffeine works by blocking the brain’s adenosine receptors (adenosine is a brain chemical that makes you feel sleepy and sluggish). Preventing you from feeling tired is how it helps fuel your marathon library sessions.
How much is too much?
Caffeine is OK in moderation. Experts say up to 400 milligrams per day is generally considered safe. “This translates to 2–3 cups of eight ounces of coffee a day, or 4–10 cups of tea depending on how strong you like your tea,” says Dr. Tellier. Keep in mind that the actual caffeine content varies widely among caffeinated beverages and serving sizes.
Going over that 400 milligram mark can be problematic. “When consumed in excess, caffeine [can have] negative effects, such as insomnia, headaches, irritability, and nervousness,” says Dr. Catherine Pound, Associate Professor of Pediatrics at the University of Ottawa in Ontario.
What did having too much caffeine feel like for students?
“My hands were shaking uncontrollably, my heart was racing, my mouth was dry, and I felt very nauseous and dizzy/off balance. I also had difficulty concentrating. The symptoms were very sudden and aggressive. They remained for several hours before slowly dissipating.”
—Melanie S., third-year undergraduate, Queen’s University, Ontario
“At first, it helped me focus and feel alert, but after a while, it started to give me butterflies in my stomach like I was nervous. That feeling made me nervous about what I had to get done, and ultimately counteracted the alertness the caffeine had initially been having on me.”
—Iona L., second-year graduate student, University of Victoria, British Columbia
“I felt like I had put a fork in an electrical socket.”
—Chris L., second-year undergraduate, University of New Brunswick
Will caffeine help you ace that test? Maybe
Caffeine isn’t all bad. A jolt of joe can boost your memory power for up to 24 hours, according to a study published in Nature Neuroscience. Participants who were given 200-milligram caffeine tablets after studying a series of images were better at distinguishing them from similar images when tested the next day, as compared to their caffeine-free peers.
You don’t have to drink coffee—just think coffee
Even more interesting? Some research suggests just the thought of downing caffeine is enough to boost your grade on a test. When researchers gave study participants a decaf beverage but told them it was caffeinated, they performed better on tests (just like participants who actually got caffeine), according to the findings published in Psychopharmacology.
Why? The powers of perception around caffeine are strong, says Dr. Candace Dye, Assistant Director of the Pediatric Residency Program at the University of Alabama at Birmingham School of Medicine. “People think ‘this is the way I’m supposed to act when I drink coffee’ and buy into it.’’
Caffeine’s side effects
The flip side of caffeine is that it can negatively affect your sleep and anxiety levels, and even contribute to panic attacks and blood pressure problems. Here’s how:
It’s a no-brainer that caffeine impairs sleep, but research shows it does more than just keep you from nodding off in class. It can mess up your total sleep schedule because caffeine can stay in your bloodstream for up to 10 hours, according to the American Academy of Sleep Medicine. That can be a major problem for students. “Caffeine interferes with the sleep-wake cycle,” says Dr. Pound. “Avoid consuming caffeine in the late afternoon, especially if you’re having trouble falling asleep at night.”
“It can be easy to get into a negative spiral of using caffeine to try to correct for inadequate sleep, but that caffeine you consume may again prevent you from getting enough sleep,” says Dr. Davis Smith, Director of Health Services at Westminster School in Connecticut. “Occasional caffeine is fine, but adequate sleep is critical to good learning because of how it benefits your concentration and memory.”
The stimulation you get from a shot of espresso can be less than ideal for your anxiety levels. Adolescents who ingested the most caffeine each day had higher scores of anxiety and depression than those who ingested the least, according to a 2016 study published in the Korean Journal of Family Medicine.
Caffeine can increase heart rate and blood pressure, according to Harvard researchers, and that can lead to health problems, including panic attacks and nausea. While it might sound extreme, ending up in the hospital because of too much caffeine occasionally happens. Dr. Robert Glatter, Emergency Physician at Lenox Hill Hospital in New York, has seen many young patients in the ER who have spiking blood pressure and irregular heartbeats from caffeine overload. “I always ask them what they drank or ate, and a lot of times it’s the caffeine that’s causing these scary symptoms,” Dr. Glatter says.
How to cut back on your caffeine consumption
As with most things, moderation is key. It probably wouldn’t hurt for most of us to cut back on our caffeine consumption—especially if we find ourselves having a hard time falling asleep at night or feeling particularly needy for that next cup.
If you’re ready to reduce your caffeine intake, first do the math. “Coffee is just one of many ways we get caffeine. It’s important to take a look at your whole day to see how much you’re consuming,” says Dr. Dye. If you start your day with a large coffee, grab a pop between classes, and sip tea during your evening study session, you’re racking up over 600 milligrams of caffeine—and you may not even realize it.
According to a recent Student Health 101 survey, 60 percent of students across Canada who consume caffeine have tried to reduce their consumption. But “stopping caffeine intake isn’t simple,” says Dr. Tellier. “If you want to stop or cut back, you might have to expect to deal with symptoms such as fatigue, irritability, difficulty concentrating, and headaches.”
But keep in mind, these symptoms might just be present in the beginning as your body gets used to the change—they’re not forever. “These symptoms increase for about three days and then disappear within a week or so,” says Dr. Tellier. “The good news is not everyone has symptoms, so give it a try.”
How to cut back without turning into a zombie
1. Go half and half.
Order a half-caffeinated/half-decaf drink in the a.m. or add more water to your home brew to dilute the caffeine in your daily coffee instead of downing your usual high-octane version, suggests Dr. Mary M. Sweeney, an instructor at the Department of Psychiatry and Behavioral Sciences at Johns Hopkins University School of Medicine in Baltimore. “Relatively small amounts of caffeine can help relieve withdrawal symptoms, so combining a mostly decaffeinated beverage with a small amount of caffeinated coffee may be a helpful strategy to cut back,” she says.
2. Think small.
A typical travel coffee mug can hold around 14–30 ounces on average—that’s anywhere from double to almost quadruple a standard cup of joe! If you take your coffee to go, trade in your oversized travel mug for an 8-ounce single-serving to-go mug.
3. Sneak in a snooze.
To combat the grogginess you’re likely to feel when cutting back on caffeine, take a power nap (as long as it’s before 3 p.m. so it doesn’t mess with your nighttime sleep). A 20- to 30-minute nap can boost mood, alertness, and performance, according to the National Sleep Foundation. Find out more about napping here.
“A quick 20-minute nap always leaves me feeling alert and recharged.”
—Hejer M., first-year graduate student, University of Victoria, British Columbia
4. Look for low-caf.
Switch up your favourite beverages for something similar but with less caffeine. Swap pop for a green tea kombucha, which typically contains less than 30 milligrams of caffeine, or switch your evening Earl Grey for a caffeine-free herbal tea. “Replacing a caffeinated drink with a low-caf or decaf one is a good place to start,” Dr. Pound says.
“I tried to fool myself by drinking decaf teas or rooibos teas with milk. I was tired at first, but it worked after a while. I consume less caffeine now.”
—Sophie L., fourth-year undergraduate, Queen’s University, Ontario
“At first, I started to drink less coffee and more tea. I went from drinking 3–4 [big] cups of coffee a day to drinking black tea to drinking a lightly caffeinated tea, until I felt like I didn’t need it anymore to keep the headaches away.”
—Laura T., second-year undergraduate, University of Victoria, British Columbia
5. Say hello to H2O.
Aim to get your water intake to be greater than your caffeinated beverage intake, says Dr. Pound. If you regularly drink a lot of caffeine, cutting back may mean experiencing some withdrawal symptoms, such as headaches or nausea, but keeping yourself hydrated by drinking lots of water will help. Bonus: Sipping on water will give your hands and mouth something to do when you crave a soft drink.
“Caffeine is a mild diuretic, which means you’re dehydrating yourself, so you need more water to feel good/normal. It also makes you feel more alert. [I’ve found] starting my day with a bottle of water can wake me up really fast and hydrate my body after a long night of sleep.”
—Lindsay M., fifth-year undergraduate, Queen’s University, Ontario
6. Snack smarter.
Swap a high-protein snack for your caffeine crutch to keep your energy up naturally. Healthy, fatigue-fighting snacks should be rich in protein, fibre, and whole grains (e.g., multigrain toast with nut butter and sliced fruit). Plus maintaining a healthy, balanced diet will help avoid the hunger that can worsen the effects of caffeine withdrawal.
7. Sleep smarter.
Reaching for cappuccino number three can seem like the only way to stay awake through a monster study session. But there’s another solution: sleep. If you can’t fit more hours of sleep into your crazy-packed schedule, focus on improving the quality of the sleep you do get by keeping your bedroom cool (use a fan if you need to) and dark, and switching your phone to night mode to cut down on the blue screen light that can mess with your internal clock. Find more useful sleep tips here.
“I used to drink coffee to keep me energized for long work shifts or long nights of studying, but I realized that leading a healthier lifestyle is more beneficial and efficient than a cup of coffee. I began to exercise more, therefore I slept more, which led me to feel very rested each morning. It was a little hard at first, but after about a week or so I didn’t crave the need for it.”
—Hasel V., fourth-year undergraduate, University of Windsor, Ontario
8. Set a caffeine curfew.
On that note, enjoy your caffeine at least six hours before bedtime to get the sweetest Zs. A dose of caffeine any closer to bedtime can significantly disturb your rest, according to a study published in the Journal of Clinical Sleep Medicine.
9. Explore new ways to stay alert.
Fitness breaks can help you stay perked up while reducing your caffeine quota. Just walking or running up and down stairs for 10 minutes can lower fatigue and boost energy, according to a 2017 study in Physiology & Behavior.
“I went from drinking coffee to green tea. Then drinking green tea every other day. Then realizing I felt much better drinking water, eating well, sleeping well, and exercising.”
—Cody L., second-year graduate student, University of Victoria, British Columbia
The bottom line: Everyone is affected by caffeine differently, so there’s no surefire way to predict how quitting cold turkey or loading up on large coffees would affect you. Your best bet for cashing in on the benefits of caffeine without any of the health risks is to notice how your body feels when you consume it and try to keep your consumption in check.
Candice Dye, MD, Pediatrician and Assistant Director, Pediatric Residency Program, School of Medicine, University of Alabama at Birmingham.
Robert Glatter, MD, Emergency Physician, Lenox Hill Hospital, New York.
Catherine Pound, MD, Associate Professor of Pediatrics, University of Ottawa; Pediatric Consultant, Division of Pediatric Medicine, Children’s Hospital of Eastern Ontario.
Pierre-Paul Tellier, PhD, Family Physician, CLCS de Côte-des-Neiges, McGill University, Quebec.
Mary M. Sweeney, PhD, Ibehavnstructor, Behavioral Pharmacology Research Unit, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.
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