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7 Things You Know About Coffee That Are Totally Wrong, Say Experts

Those 'facts' you've believed for years are actually not true.
FACT CHECKED BY Olivia Tarantino

You're in the minority if you aren't pouring yourself at least one cup of coffee every day. According to Statista, in 2020 Americans consumed an average of 1.87 cups of joe per day!

Whether you're grabbing coffee for the taste, an energy boost, or simply to warm yourself up, coffee is so prevalent in our society that many of us don't think twice about this caffeinated beverage. But what you may not realize is that many of the "truths" we know about coffee may actually be wrong. We asked registered dietitians to bust the 7 most common coffee myths that people have believed to be true all these years. Read on, and for more on healthy eating, don't miss 7 Healthiest Foods to Eat Right Now.

If you're diabetic, you can't drink coffee.

iced coffee

Believe it or not, drinking more coffee significantly reduces a person's risk of developing diabetes.

"A person's risk of developing type 2 diabetes reduces by 7% per 1 cup of coffee per day," says Roxana Ehsani, MS, RD, CSSD, LDN, Registered Dietitian Nutritionist, and Spokesperson for the Academy of Nutrition and Dietetics. "Individuals with increased risk of developing diabetes should consider adding a cup of coffee into their day. Reduced coffee intake was associated with a higher risk of type 2 diabetes. Even decaffeinated coffee has the same diabetes reducing effects."

Just be wary of ordering a cup of coffee with added sugar, syrups and/or creamers as these will make your cup of coffee not so healthy.

"Instead opt for black coffee, or coffee with a splash of low-fat milk or non-dairy milk alternative," says Ehsani.

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Instant coffee has no health benefits.


"Some people believe that instant coffee, due to the way it is processed, loses coffee's natural beneficial compounds, but this is not true," says Carissa Galloway, RDN, registered dietitian nutritionist and Premier Protein nutrition consultant. "Coffee is linked to an abundant supply of antioxidants and while instant coffee may not have as high of a concentration as brewed coffee, those antioxidants are still present. Now, I can't weigh in on the myth that instant coffee isn't as tasty as brewed coffee…that one is up to whoever is drinking the coffee!"

It's dehydrating.

Man barista making coffee latte

"Yes, coffee is a slight diuretic… however, since it is a liquid, the diuretic effects are balanced out by the amount of water it contains," says Amy Shapiro MS, RD, CND, registered dietitian, and Daily Harvest Nutrition Partner. "In a study published in PLOS One, researchers looked at the blood and urine of participants who drank either coffee or an equivalent amount of water over a period of three days and found no significant difference in hydration levels."

You shouldn't drink coffee before physical activity.

Starbucks cup of coffee at a table with a notepad

"Coffee is a performance enhancer, also known as an ergogenic aid. By adding caffeine before or during exercise, athletes may see an increase in both physical and mental performance," says Ehsani. "Athletes may also notice decreased pain and perception of fatigue during exercise, decreased perceived exertion, improved performance in endurance and in high-intensity training and even increased ability to focus and concentrate."

Before deciding to drink a cup or two of coffee before a big game, race, or event, be sure to test it out first.

"The rule of thumb is to consume 2-6 milligrams of caffeine per kg of body weight, so for a 150-pound person 1 to 3 cups of brewed coffee 1 hour before your activity," says Ehsani. For more, don't miss 14 Best Foods for Better Workout Results, According to Experts.

Tasty coffee drinks are just empty calories.

drinking coffee

Most dietitians will tell you that a daily 300-calorie latte might not be the best habit if you're looking to lose weight or reach other wellness goals, but that doesn't mean that all coffee drinks are off-limits.

"Coffee on its own is very low calorie, about 1 calorie per cup of black coffee. Therefore, the issue isn't the coffee, but what you put in it. TikTok got it right when it came to making a tasty coffee that supports your wellness goals with the #proffee trend," says Galloway.

FYI, "proffee" = protein + coffee.

"Next time you visit your local coffee house, skip the seasonal high-sugar latte and ask for 2 shots of espresso on ice in a venti cup. Then, add a ready-to-drink protein shake to the ice and espresso. Now you have a delicious coffee 'latte' with satisfying protein, instead of flavored syrups that will spike your blood sugar. The "proffee" trend is perfect as a morning wake-up call or a midday boost, and is dietitian-approved," says Galloway. (Related: The Amazing Health Benefits of Spiking Your Coffee With Protein Powder.)

It will stunt teenagers' growth.

drinking coffee

"Early research was done on elderly individuals who showed signs of osteoporosis; however, they did not consume enough calcium. Coffee has been shown to decrease calcium absorption, but 1-2 tablespoons of dairy milk is enough to balance that out. So if your teen needs a boost, my recommendation is to make sure they avoid the sugar!" says Shapiro.

Coffee isn't healthy.


You may be surprised to learn that your cup of coffee is loaded with some powerful nutrients.

"Coffee contains antioxidants, potassium, niacin, and magnesium. Coffee is the leading source of antioxidants in Americans' diets!" says Ehsani. "Drinking coffee has been associated with lower risks of some cancers, decreased risk of developing type 2 diabetes, decreased metabolic disease risk, lower risk of developing liver disease, lower risk of Parkinson's disease, lower risk of depression and Alzheimer's disease." For more on this energizing beverage, don't miss 8 Awesome Side Effects of Drinking Coffee, According to Dietitians.

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