Americans drink coffee regularly, and a lot of it, too. In fact, according to The National Coffee Association, coffee is the number one drink consumed by Americans daily. Yep, that’s even more than water, folks.

But how does consuming coffee day in and day out impact your body? We caught up with Sarah Robbins, MD, MSc, FRCPC, a gastroenterologist, gut health expert, and the founder of Well Sunday, who shared more about the potential long-term effects—both positive and negatives—of drinking coffee regularly. Although the beverage can affect everyone differently, here’s the 10 most common long-term side effects of drinking coffee you need to know.

5 positive long-term side effects of drinking coffee regularly

Dr. Robbins shares the beneficial effects of drinking coffee every day for overall well-being. But, like most things in life, it’s important to consume the beverage in moderation to reap its benefits.

1. It has anti-inflammatory benefits

According to Dr. Robbins, coffee is a great source of antioxidants—researchers even found that coffee is the number one source of antioxidants in the American diet. “Caffeine contains antioxidants, which are compounds that help protect your cells against damage from free radicals, potentially reducing inflammation and improving health outcomes,” Dr. Robbins says. She also notes that antioxidants can help stave away various chronic diseases.

2. It can boost cardiovascular health

Moderate caffeine consumption has been associated with a lower risk of certain cardiovascular diseases, including strokes, says Dr. Robbins. “The mechanism may involve caffeine’s antioxidant properties and its ability to improve endothelial function, the functioning of the inner lining of blood vessels,” she explains. However, she notes this doesn’t apply to excessive caffeine (or coffee) consumption. “It’s important to note that excessive caffeine intake can cause a temporary increase in heart rate and blood pressure, so moderation is key,” she adds.

3. It can support brain health

Dr. Robbins says research has demonstrated a link between coffee and reduced risk of developing neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases. “The protective effects might be due to caffeine’s ability to block adenosine receptors, which are involved in the pathogenesis of these diseases, as well as its antioxidant properties,” she says.

4. It has protective liver benefits

Coffee and caffeine intake may offer protective benefits against liver diseases. “Regular caffeine intake has been associated with a lower risk of liver fibrosis—scarring of the liver—in individuals with liver disease,” Dr. Robbins says. “Caffeine may also protect against the development of non-alcoholic fatty liver disease (NAFLD) and liver cancer,” she adds. According to a large study conducted in 2021, folks who drank coffee had a significantly lower NAFLD incidence. Another older study also found that consuming roughly two cups of coffee a day could help reduce the risk of liver cancer by potentially 43 percent.

5. It has anticancer properties

Caffeine consumption is also associated with anticancer properties. “Some epidemiological studies have found an association between caffeine consumption and a reduced risk of certain types of cancer, including liver and colorectal cancer,” Dr. Robbins says. The research attributes this to caffeine’s ability to enhance DNA repair, its antioxidant properties, and its effects on liver enzymes, Dr. Robbins explains.

5 potentially negative long-term side effects of drinking coffee regularly

There is such a thing as too much of a good thing. Dr. Robbins says there are a few potential downsides to drinking coffee—particularly in excess—all the time. The key takeaway: Be mindful of how much you’re drinking in a day. “While caffeine consumption can offer various health benefits, it’s crucial to acknowledge that long-term or excessive intake can lead to several adverse effects. Understanding these risks is important, especially for certain populations and individuals with heightened sensitivity to caffeine,” she says.

1. It may impact sleep regularity

Indeed, coffee contains a substantial amount of caffeine, which can impact the quality of your shut-eye. “Caffeine can disrupt sleep patterns, delay sleep onset, and reduce sleep quality and total sleep time. This is because caffeine blocks adenosine, a neurotransmitter that promotes sleep,” Dr. Robbins says. For context, there’s about 80 to 100 milligrams of caffeine per eight-ounce cup of coffee and the USDA recommends consuming no more than 400 milligrams of caffeine daily.

A 2023 study found that caffeine consumption could reduce total sleep time by 45 minutes and sleep efficiency by seven percent. However, in order to reduce the effects caffeine has on the body, Dr. Robbins recommends simply timing coffee consumption accordingly, aka early enough so it won’t keep you up at night, as well as consuming it in moderation.

2. It may trigger migraines and headaches

Moderate amounts of caffeine can reduce headache symptoms for some people, but it can be triggering for others. “For some individuals, especially those prone to migraines, caffeine can trigger headaches or exacerbate migraine symptoms,” Dr. Robbins says. The key? Adequately hydrating (with water!) and limiting your caffeine intake.

3. It may increase eye pressure

According to Dr. Robbins, increased caffeine consumption can potentially impact eye health, although the effects are typically fast-acting and, fortunately, fast-dissipating. “Caffeine can cause a temporary increase in intraocular pressure (IOP), which could be a concern for individuals with glaucoma or high eye pressure,” she says.

4. It may negatively affect younger people

Coffee consumption can also pose negative risks for children and adolescents. “High caffeine intake may affect the neurological development of children and adolescents and may lead to increased anxiety, disturbed sleep patterns, and potentially affect cardiovascular function,” Dr Robbins explains. As such, she recommends children and adolescents limit caffeine intake as much as possible. “[Children and adolescents should] focus on consuming nutrient-rich, caffeine-free beverages instead,” she says.

5. It may affect pregnancy

Dr. Robbins says caffeine can potentially impact pregnancy. “Caffeine crosses the placenta, and because fetuses have a limited ability to metabolize caffeine, it can potentially impact fetal development,” she says. “Some studies suggest a link between high caffeine intake during pregnancy and low birth weight, preterm birth, or increased risk of pregnancy loss. There’s also concern that high caffeine consumption during pregnancy could affect the cognitive development of the offspring and increase their susceptibility to diseases in adulthood,” she says.

According to The American College of Obstetricians and Gynecologists (ACOG), pregnant women are often advised to limit their caffeine intake to less than 200 milligrams per day, which is the equivalent of about one 12-ounce cup of coffee. Even so, it’s best to consult with a doctor to best determine intake for your particular needs.

Bottom line

Although consuming coffee regularly can have several long-term benefits, such as anticancer, anti-inflammatory, and cardiovascular support, there are a few considerations to keep in mind. This is particularly true for folks who tend to consume a lot of caffeine. In short, Dr. Robbins says if you tolerate caffeine well, coffee has its benefits, but should always be consumed in moderation.

RD shares the health benefits of drinking coffee:

—reviewed by Jennifer Logan, MD, MPH