An estimated 175 million Americans drink coffee every day — that’s nearly 3 in 4 people in the U.S. going on a morning coffee run, having an iced coffee as an afternoon pick-me-up or enjoying an espresso with dessert. For many people, coffee is more than just a habit or a way to start the day. Brewing coffee can be a comforting morning ritual, a reason to gather with friends and family, or even a hobby for those interested in different roasts and drink styles. Still, for as widespread as coffee drinking is, there’s some confusion around the beverage and its impact on health.
“One of the things that I and other healthcare professionals hear all the time during appointments is a patient saying, ‘Doc, I’m drinking too much coffee,’ ” says Donald D. Hensrud, M.D., M.S., medical editor of “The Mayo Clinic Diet.” “And I’ll say, ‘Why?’ People think coffee isn’t good for you and that’s really not the case.”
In fact, Dr. Hensrud says coffee has a number of significant health benefits — including reducing your risk of certain chronic conditions and cancers and even depression. However, there are a few important factors and side effects to keep in mind when determining the right amount of coffee for you.
Below, Dr. Hensrud discusses the health benefits and side effects of coffee —and signs it may be time to cut back.
Coffee — An unexpected ally for wellness
It will likely come as no surprise that coffee can offer a range of cognitive benefits, including increased alertness and improved mental performance. But research also indicates that moderate coffee drinkers have a lower risk of Alzheimer’s disease — one of the most common forms of dementia.
Drinking coffee —up to four or even five cups a day — also offers a number of lesser known health benefits that can impact the entire body. “In coffee drinkers, there’s a decreased risk of type 2 diabetes, Parkinson’s disease, liver disease, certain cancers including liver cancer, depression and suicide, kidney stones and gallstones, and overall mortality,” says Dr. Hensrud. Additionally, some studies suggest that coffee consumption may lower the risk of cardiovascular disease and mortality.
These benefits aren’t solely linked to coffee’s caffeine content either. “Many people don’t realize that the decreased risk of Parkinson’s is related mainly to caffeine, whereas the type 2 diabetes risk is not,” Dr. Hensrud explains. “You see a decreased risk of type 2 diabetes both in people who consume caffeinated and decaffeinated coffee.”
In fact, coffee has hundreds of different components, including important micronutrients such as magnesium, potassium, niacin and vitamin E, as well as antioxidants that help protect your cells from damage and harmful free radicals. According to Dr. Hensrud, coffee is often the largest, most consistent source of antioxidants in the diet for those who drink it regularly.
However, Dr. Hensrud says coffee — and caffeine in all its forms — may be associated with an increased risk of miscarriage. “It’s recommended that those who are trying to get pregnant or who are pregnant should limit their caffeine intake to 200 milligrams of caffeine, which is about the amount in two 8-ounce cups of coffee,” says Dr. Hensrud. “Keeping consumption even lower may be beneficial, as caffeine may decrease iron absorption as well.”
Finally, some medications may interact with caffeine — so it’s always a good idea to talk with your healthcare team about possible side effects or drug interactions.
How much coffee is too much?
In addition to having health benefits, coffee can cause a number of side effects. Some may or may not impact you, depending on how much coffee you drink and how your body processes caffeine.
According to Dr. Hensrud, common side effects include problems sleeping, benign heart palpitations, feeling jittery or nervous, worsening of acid reflux and heartburn, gastrointestinal upset, and urinary symptoms like frequent urination or urgency. Caffeine is mildly addictive as well, meaning many people experience headaches if they skip coffee one day or don’t have as much as usual.
If you’re drinking coffee throughout the day but aren’t sure if you’re experiencing any side effects, Dr. Hensrud recommends cutting back on your consumption and observing what happens.
“People need to be aware of the side effects,” says Dr. Hensrud. “They can be subtle, especially if someone is a slow metabolizer. The half-life of caffeine is about six hours or so, but it can be a lot longer, so coffee may be causing side effects that people aren’t totally aware of.” If you’re having ongoing trouble sleeping well, for example, you may be able to resolve the problem by drinking fewer cups of coffee.
“But if somebody isn’t having side effects, there’s no reason to cut down,” says Dr. Hensrud.
Finally, it’s important to remember that not all caffeinated drinks are made equal. Powders and instant coffee mixes may contain toxic doses of caffeine. A single teaspoon of powdered caffeine, for example, can equal over 2 dozen cups of coffee. Energy drinks — especially when mixed with alcohol — can cause serious health conditions and even death. Many people also take their coffee with a number of additives, such as artificial flavorings, sugar and cream, which can add a large number of calories. When possible, try to opt for no sugar and stick to skim milk or unsweetened nondairy alternatives.
The bottom line on coffee
Coffee does offer significant health benefits for many people, says Dr. Hensrud. “If you enjoy your coffee, just look out for the side effects. If you’re having any side effects, or suspect you might be, try cutting down and seeing if the side effects get better.”
People taking certain medications and those who are pregnant or are trying to become pregnant should limit their caffeine and coffee intake. But for the average person, Dr. Hensrud says to rest assured that your coffee intake can actually protect your health. “If you like it, enjoy your java,” says Dr. Hensrud.
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