Coffee is one of the most consumed beverages in the world, and with its popularity comes a flood of myths, rumors, and half-truths. Over the years, coffee has been blamed for everything from stunting your growth to causing dehydration. But how much of it is actually true?
Let’s take a closer look at some of the most common coffee myths—and reveal what the science really says.
Myth 1: Coffee Stunts Your Growth
This is perhaps the most well-known myth—and completely untrue. There’s no scientific evidence that coffee affects height or bone development.
The Truth:
Coffee does not interfere with growth hormones or bone density in a way that could stunt your height. This myth likely emerged from outdated concerns about caffeine’s effect on calcium absorption. Even then, any impact is minimal and easily offset with a balanced diet.
Bottom Line:
Drink up. Coffee won’t shrink you.
Myth 2: Coffee Dehydrates You
Because caffeine is a mild diuretic, many people assume coffee will leave you dehydrated. While this was a common belief for years, it doesn’t hold up under scientific scrutiny.
The Truth:
Coffee contains water, and the fluid intake from drinking coffee outweighs its diuretic effect. For regular coffee drinkers, the body adapts, and there’s no significant risk of dehydration.
Bottom Line:
Coffee contributes to your daily hydration—especially when consumed in moderation.
Myth 3: Dark Roast Has More Caffeine
A lot of people assume that the stronger, bolder flavor of a dark roast means more caffeine. But the opposite is often true.
The Truth:
Light roasts typically have slightly more caffeine than dark roasts by volume. The roasting process reduces caffeine content slightly as the beans expand and lose density.
Bottom Line:
Don’t let flavor intensity fool you—light roast packs a bit more punch per scoop.
Myth 4: Coffee Causes Insomnia in Everyone
Yes, caffeine can disrupt sleep—but it doesn’t affect everyone equally, and timing is everything.
The Truth:
Caffeine’s half-life is about 5–6 hours, meaning half of it remains in your body after that time. For sensitive individuals or those who drink it late in the day, it can absolutely affect sleep. But for others with faster metabolism or higher tolerance, moderate coffee intake earlier in the day has little to no impact.
Bottom Line:
Know your limits. If you sleep well after an afternoon cup, you’re probably fine.
Myth 5: Coffee Is Addictive Like a Drug
Many equate their morning coffee cravings with addiction. While caffeine dependence is real, it’s not the same as a substance addiction.
The Truth:
Coffee can create mild physical dependence, and sudden withdrawal may cause headaches or irritability. But it does not cause compulsive behavior, significant harm, or social dysfunction like addictive drugs.
Bottom Line:
It’s a habit, not a hard addiction. Most people can reduce or quit coffee gradually without serious issues.
Myth 6: Pregnant Women Should Avoid Coffee Completely
Pregnancy advice often includes avoiding coffee altogether. But the reality is more nuanced.
The Truth:
Most health organizations, including the World Health Organization (WHO) and American College of Obstetricians and Gynecologists (ACOG), say 200 mg of caffeine per day (about one 12 oz cup of coffee) is safe during pregnancy.
Bottom Line:
Moderation is key. Always consult your doctor, but total avoidance isn’t necessary for most.
Myth 7: Coffee Is Bad for Your Heart
Coffee has long been linked to heart palpitations and high blood pressure, leading some to believe it’s harmful to cardiovascular health.
The Truth:
Studies now show that moderate coffee intake is associated with a lower risk of heart disease and stroke. While caffeine can cause a short-term rise in blood pressure, it typically stabilizes over time for regular drinkers.
Bottom Line:
If you have heart issues, talk to your doctor—but for most people, coffee supports heart health when consumed in reasonable amounts.
Myth 8: Decaf Coffee Is Completely Caffeine-Free
If you order decaf expecting zero caffeine, you might be surprised.
The Truth:
Decaf coffee still contains a small amount of caffeine—usually between 2 to 7 mg per cup. For comparison, regular coffee has 70–140 mg. While this might not affect most people, it’s good to know if you’re highly sensitive to caffeine.
Bottom Line:
Decaf is low in caffeine, not caffeine-free.
Myth 9: Coffee Is Bad for Your Bones
This myth is rooted in the idea that coffee leaches calcium from bones. While excessive caffeine without calcium intake may have some impact, it’s not a concern for most people.
The Truth:
Studies have found that moderate coffee consumption doesn’t cause osteoporosis or weaken bones, especially if calcium intake is adequate.
Bottom Line:
Enjoy your coffee and keep up with your daily calcium—your bones will be fine.
Myth 10: Coffee Causes Cancer
Some alarmist headlines have linked coffee to cancer risks. But those fears are largely unfounded.
The Truth:
In 2016, the World Health Organization removed coffee from its list of possible carcinogens. In fact, recent studies show coffee may help reduce the risk of certain cancers, including liver and colorectal cancer, due to its antioxidants and anti-inflammatory compounds.
Bottom Line:
Rather than a risk, coffee might actually be protective against some cancers.
Final Thoughts: Know the Facts, Enjoy the Brew
Coffee is one of the most studied beverages in the world. And while it’s not perfect for everyone, many of the old myths don’t hold up to modern research.
When enjoyed in moderation, coffee is:
- Hydrating
- Heart-healthy
- Full of antioxidants
- Safe during pregnancy (in limited doses)
- Unlikely to interfere with growth or bone health
So sip your brew with confidence—science is on your side.