Growing up, my parents always told me caffeine was bad for you.
“It stunts your growth,” they would say, citing my older brother as an example.
As someone who drank soft drinks and still didn’t budge at 4 feet 10 inches throughout middle school, my brother was perfect fodder for my parents’ bases. But since he’s now 6-foot-tall and his craving for Coca-Cola hasn’t subsided, I’ve become skeptical of my parents’ theory—could caffeine be so terrible for you?
My questions increased as the school year began, after Harvard student agencies delivered four cans of Red Bull to our dormitories during my first week on campus. Here was an energy drink that I had always thought of as poison served publicly and institutionally.
However, this was not an isolated event. Caffeine seems to be rampant at Harvard. In my class at 10:30 am, at least three to four students around me drink coffee or tea on a regular basis. I’ve seen more Red Bull flavors in one class than ever before (yes, there’s more than just a blue can), and I’ve even heard discussions about caffeine pills.
But what Harvard students may fail to realize is that caffeine is a drug. More specifically, it is a drug that is well absorbed by our bodies, with the ability to mimic the look and feel of adenosine, a sleep-inducing neurotransmitter, in our brains. Caffeine binds to adenosine receptors and prevents the neurotransmitter from producing its effects, which not only enhance the firing of excitatory neurons, but also stimulate the brain’s reward centers using dopamine, the juice of pleasure. Opioids, cocaine, and alcohol are all drugs that can increase dopamine levels in our brains and lead to pleasure-seeking cravings similar to those associated with caffeine.
As interesting as this may be, I highly doubt anyone is considering the neurochemistry behind the increase in dopamine levels when enjoying their morning cup of joe.
Having a cup of caffeine in the form of tea or coffee in the morning is an ingrained habit in American society. Take, for example, Massachusetts-based Dunkin Donuts, whose slogan “America Runs on Dunkin'” perfectly captures the idea that coffee fuels us for the day.
Coffee is central to student meetings, appointments, and studying—so much so that some libraries, like the Cabot Science Library, even boast a coffee shop to attract students. The coffee industry generates billions of dollars in annual profits, and the average American spends over a thousand dollars on coffee each year. It really is the most popular drug in the country.
But why is there such a nationwide reliance on caffeine? Although taken in small doses can boost your morale or energy levels, high doses of caffeine, like any stimulating drug, can be addictive.
When we drink more and more coffee, for example, we need higher and higher doses to reach similar levels of alertness, which can lead to a phenomenon known as tolerance that can ultimately be harmful. Tolerance explains why, with time, your morning cup of coffee just doesn’t do the trick, and running Starbucks in the middle of the day becomes an absolute necessity. Over time, your body becomes dependent on caffeine. Levels of excitatory neurotransmitters like norepinephrine drop, and your body begins to rely on caffeine to achieve that exciting high.
This is where caffeine can get dangerous. Drinking more than 400 mg of caffeine a day — the equivalent of four cups of regular coffee or roughly two “energy shot” drinks — can lead to health problems. In the short term, caffeine consumption can cause insomnia and anxiety. And in the long run, while it’s not likely to stunt your growth (much to my dad’s annoyance), it can lead to digestive issues, dehydration, and high blood pressure.
As a student, the allure of caffeine makes sense: Drink a cup of coffee or an energy drink, get some extra energy, and you’ll likely get a few more hours of productivity. That sounds like a bargain — and it’s probably at least part of the reason why I used coffee in the first place. There is a popular origin story that mentions an Ethiopian shepherd who saw his flock of sheep “dance” after eating coffee beans. Afterwards, he shared the beans with a monk who used them to keep his attention for a late-night prayer.
In other words, according to this legend, monks used caffeine to pull people through the night—and if that use applies to monks, then it certainly applies to excited college students.
But, unfortunately, drinking caffeine to delay sleep can be dangerous. We basically end up tricking our bodies into the rest and recuperation needed to be alert and productive. Caffeine brings false happiness to our brain, even though the rest of our body might say otherwise.
It’s hard to tell people to stop consuming caffeine. Even if it doesn’t seem to have many immediate effects, just expecting a placebo of an energy spike can make drinking a caffeinated beverage worthwhile.
So here’s my take: Like anything in life, caffeine consumption is OK in moderation. Science tells us that extremes like taking a caffeine pill to stay awake or drinking energy drinks won’t do you any good in the long run, but a Mocha Frappuccino might actually do.
Sandhya Kumar ’26 lives at Greenough Hall. Her column, “Science ‘n Tradition,” runs on rotating Tuesdays.