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Surprising Side Effects of Drinking Black Coffee, According to Dietitians

If you skip cream and sugar, you're going to want to read this.

Coffee is a morning staple that many people drink to give them the energy to get through the day. Whether you head to Starbucks or Dunkin' for your favorite cup of joe or make it at home, when's the last time you had it black? Unless you are part of the minority who prefers their coffee black, chances are you likely add in a splash of creamer, sugar, milk, etc. However, there are surprising side effects of drinking black coffee that you probably have never thought about until now.

"In addition to helping you wake up each morning, black coffee has several health benefits including reducing the risk for Type 2 diabetes, cancer, liver disease, and heart disease," says Lisa Andrews, MEd, RD, LD, Owner of Sound Bites Nutrition.

Keep on reading to discover what else this beloved morning beverage could do for your wellbeing.

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Black coffee can help your gut

Man Pouring Coffee from Pot

For those with digestive issues, black coffee might be your next saving grace. "Coffee may aid in keeping your gastrointestinal tract healthy by creating a healthy gut microbiome," says Andrews.

You might be familiar with the feeling of having to rush to the bathroom after a cup of black coffee, well that's in part because it helps to keep things moving. According to Zoe, some compounds in coffee help stimulate the production of stomach acid which aids in moving food through your gut and keeping you regular.

Black coffee may help prevent some diseases

black coffee healthier

As briefly mentioned above, black coffee may be effective in reducing the risk for diseases like Type 2 diabetes, cancer, liver disease, and heart disease.

"Coffee provides several bioactive substances such as phenolic compounds (cafestol and kahweol), alkaloids (caffeine and trigonelline), diterpenes, and other metabolites that may aid in disease prevention," says Andrews. A study from the AHA Journal Circulation: Heart Failure which analyzed the Framingham Heart Study, indicated the risk of heart failure over time decreased between 5% and 12% for each cup of coffee consumed each day compared to those who didn't drink coffee.

Black coffee can aid in mental health

black coffee better mood

For those with anxiety, black coffee is probably not the best idea because caffeine can make you feel even more jittery and nervous. However, for other mental health issues and cognitive impairments, this warm beverage may be helpful.

A study from the journal Molecular Psychology found that drinking coffee on a regular basis appeared to "enhance concentration and improve motor control and alertness by creating changes in the brain."

Andrews attests to the potential neurological benefits of drinking black coffee, "It's been found to reduce the risk for dementia, depression and suicidal risk."

That's not to say drinking coffee is going to completely eliminate depressive symptoms, but it can be another coping mechanism added to the toolbox for those with the illness.

Excess black coffee intake increases risk of insomnia

woman looking stressed at alarm clock when waking up in the middle of the night

This might be self-explanatory, but Andrews says drinking too much coffee can increase the chances of insomnia. According to the Sleep Foundation, excessive caffeine intake can lead to insomnia symptoms or worsen pre-existing insomnia, "Consuming caffeine to stay awake at night may lead to sleeplessness, anxiety, frequent nighttime awakenings, and overall poorer sleep quality."

It's best to drink a cup of coffee in the morning so the caffeine has more time to wear off before it's time for bed.

Black coffee can exacerbate acid reflux

black coffee

Acid reflux occurs when stomach contents move back up into the esophagus which causes a burning sensation in the throat and/or chest. According to Andrea Dunn, RD, in this article from the Cleveland Clinic, "drinking caffeinated coffee increases the amount of acid that's already in your stomach, which makes it easier for acid reflux and heartburn to take effect."

Black coffee can make for good pre workout

coffee before workout

Breanna Woods, MS RD, registered dietitian for Blogilates, shares that coffee can be a good pre-workout beverage. According to The International Society of Sports Nutrition (ISSN), caffeine has been shown to improve workout performance, for both athletes and non-athletes. Woods notes they recommend supplementing caffeine (AKA drinking your cup of coffee) about an hour before you workout.

Black coffee can help you focus

black coffee focus

Say goodbye to the brain fog with a cup of black coffee. Lauren O'Connor, MS, RDN, RYT, owner of Nutri Savvy Health and author of Healthy Cooking for One, shares that this beloved morning beverage can help improve focus.

O'Connor referenced a study in Nutrients that indicates how coffee contains over 1000 compounds including phenolics and chlorogenic acids that have been studied for their effects on focus.

A previous version of this article was originally published on May 12, 2022.

Casey Clark
Casey Clark is a current journalism student at Hofstra University with a passion for food, beauty, and entertainment. Read more about Casey
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