For many of us, coffee is more than just a drink—it’s a ritual, a comfort, and sometimes, a lifeline. But despite its popularity, coffee is often misunderstood. From claims that it stunts growth to fears that it dehydrates you, misinformation abounds.
As both a coffee lover and a science enthusiast, I decided to dig into the research and debunk four of the most persistent coffee myths. Here’s what the evidence really says.
Myth #1: Dark Roast Coffee Is Stronger (Has More Caffeine)
The Myth: Many believe dark roast coffee packs more caffeine because of its bold, intense flavor.
The Science: A 2017 study published in Nature by researchers Megan Fuller and Niny Z. Rao compared caffeine levels in medium and dark roast coffee (both from Arabica beans grown in Hawaii). Surprisingly, medium roast had a higher caffeine concentration than dark roast.
Why? Roasting breaks down caffeine slightly, meaning lighter roasts retain more caffeine despite their milder taste. If you prefer dark roast for its rich flavor, great—just know it’s not giving you an extra caffeine kick.
Myth #2: Coffee Stunts Growth in Kids
The Myth: Parents often warn kids that coffee will stunt their growth.
The Science: There’s zero evidence linking coffee consumption to growth impairment. Dr. Roy Kim of the Cleveland Clinic confirms: “Caffeine doesn’t impact growth.”
Where Did This Myth Come From? Some speculate it stems from old beliefs that caffeine affects calcium absorption (debunked) or suppresses appetite. While coffee isn’t ideal for kids due to potential sleep and anxiety issues, it doesn’t affect height or development.
Myth #3: Coffee Dehydrates You
The Myth: Since caffeine is a diuretic, many assume coffee leads to dehydration.
The Science: A 2014 PLoS ONE study tested hydration in men who drank either coffee or water. Result? No significant difference in hydration levels.
Why? While caffeine has mild diuretic effects, coffee is mostly water, which offsets any fluid loss. Unless you’re drinking excessive amounts, your morning cup won’t dehydrate you.
Myth #4: Coffee Causes Heart Disease
The Myth: Some fear coffee raises heart disease risk due to its stimulating effects.
The Science: A 2022 study by the European Society of Cardiology analyzed data from 500,000+ UK adults and found:
Drinking 2–3 cups of coffee daily (including decaf) lowered cardiovascular disease risk.
Coffee drinkers had reduced mortality rates compared to non-drinkers.
Key Takeaway: Moderate coffee consumption may support heart health rather than harm it.
Final Verdict: Enjoy Coffee—Without the Myths
Science confirms that coffee:
✔ Doesn’t have more caffeine just because it’s dark roast
✔ Won’t stunt growth in kids (though it may disrupt sleep)
✔ Doesn’t dehydrate you (it counts toward daily fluid intake)
✔ May actually protect your heart in moderation
So go ahead—brew that cup guilt-free. Just remember, balance is key.
Did any of these myths surprise you? Share your thoughts in the comments!