Coffee and tea are among the most consumed beverages worldwide. Two-thirds of American adults drink coffee daily, says the National Coffee Association’s 2025 survey, up 7 percent from 2020. In contrast, the Tea Association indicates that just under half the population drinks tea. (Some drink both beverages.) Tea attracts a younger, health-oriented crowd to new-age teahouses, a social setting akin to bars and coffeehouses.
Tea and Health Benefits
The most substantial evidence for tea’s health benefits is its association with longer life. A 2024 meta-analysis of about 1.3 million participants found that moderate tea intake (1.5 to 2 cups per day) was associated with lower all-cause mortality and lower cardiovascular and cancer mortality. A 2025 meta-analysis reported that black tea consumption was associated with a lower risk of coronary heart disease. These protective effects level off at two cups per day or more. (So you can’t drink 10 cups of tea daily and expect to live forever.)
A systematic review of green tea trials showed modest but consistent improvements in blood pressure, fasting glucose, and lipids. A substantial body of evidence links regular tea intake to a decreased risk of type 2 diabetes, with maximum benefits at 3 to 4 cups per day. Extensive analyses suggest that tea drinkers experience lower cardiovascular disease (CVD) mortality, stroke incidence, and CVD events compared to non-drinkers. Among patients with metabolic syndrome, habitual tea intake is associated with both decreased mortality and fewer cardiovascular complications.
Large Japanese and Korean cohorts with habitual green tea intake of approximately 2 to 3 cups per day (or more) have shown beneficial effects on dementia prevention. In Japan, daily consumption of 2 to 3 cups of tea was associated with a 25 percent lower risk of dementia.
A Japanese study reported that higher green tea intake correlated with significantly fewer problematic cerebral white-matter lesions, independent of vascular risk factors. This may explain why green tea drinkers had more than a third (37 percent) lower odds of cognitive impairment.
Coffee: The Evidence
Where tea data may be slightly stronger for vascular and brain-aging outcomes, coffee has robust evidence of protection against metabolic, liver, and neurodegenerative diseases, with maximal benefit around 2 to 4 cups per day. At least 50 studies show regular consumption of moderate doses of coffee decreases all-cause mortality. I have previously written about the health benefits of coffee here.
Coffee is rich in antioxidants such as chlorogenic acids, which help neutralize harmful, cancer-causing free radicals in the body. By reducing oxidative stress, these antioxidants slow cellular aging and decrease the risk of chronic diseases. Studies indicate coffee drinkers have a lower risk of neurodegenerative diseases such as Alzheimer’s and Parkinson’s.
An umbrella study of 201 meta-analyses concluded that 3 to 4 cups of coffee per day is associated with approximately 17 percent lower all-cause mortality and approximately 19 percent lower CVD mortality. Moderate intake (2 to 4 cups per day) is associated with reduced CVD mortality and slower progression from prediabetes to diabetes. One recent review suggests up to 3 cups of coffee per day may extend life by roughly two years.
A new British Medical Journal study found that the telomere length (an indicator of cellular aging) of patients with severe mental disorders tends to be shorter than that of the general population. Coffee intake within the recommended dose was found to cause changes, longer telomeres, in severe mental disorders, comparable to a five-year-younger biological age. Again, coffee consumption may reduce oxidative stress, helping prevent biological aging processes like telomeric shortening.
Coffee preparation substantially modifies risks. Analyses from multiple cohorts conclude that black or minimally sweetened coffee best retains mortality benefits. However, adding heavy sweetening or cream eliminates or reverses this benefit. Coffee also improves health in people with diabetes, cirrhosis risk, and chronic liver disease.
Sometimes timing is everything. Morning coffee intake is associated with lower mortality than late-day drinking.
Comparing the Benefits of Coffee and Tea
Both beverages are associated with favorable health outcomes across multiple domains. Generally, an 8-ounce cup of regular coffee contains about 80 to 100 milligrams (mg) of caffeine. The caffeine content of tea varies by type. For example, green tea has the highest caffeine concentration, 40 to 70 mg per 8-ounce serving. Other teas have less caffeine, and many herbal teas contain minimal, if any, caffeine.
Most guidelines consider up to about 400 mg of caffeine per day safe for healthy adults, and ≤200 mg per day in pregnancy. Regular coffee delivers a bigger caffeine punch per ounce than tea. That’s why most people reach for coffee when they need a stimulant.
Individuals with reflux, palpitations, panic disorder, or poorly controlled hypertension may tolerate tea better than coffee.
In contrast, coffee has well-documented benefits on alertness, mental acuity, reaction time, fatigue, and performance. Coffee may reduce risks for Alzheimer’s disease and cognitive decline. Meta-analyses and systematic reviews show inverse associations between coffee or caffeine and Parkinson’s disease, with moderate intake providing the highest protection. Coffee also may reduce risks for some cancers, including endometrial, colorectal, and head and neck malignancies. Pooled analyses suggest a 17 to 40 percent reduction at ≥3 to 4 cups per day.
Among all outcomes, liver protection is perhaps the strongest signal in favor of coffee. Higher coffee intake is associated with markedly reduced risk of liver cancer, cirrhosis, and other liver diseases. Protective associations often exceed 40 percent for two or more cups per day.
Summary
Both coffee and tea offer disease prevention benefits. In considering health only, the best choice depends on individual health goals, but some research suggests a combination of both may offer the broadest protection against various diseases. Ingredients, such as caffeine, are even approved by the FDA for medical use to treat fatigue or as a component of migraine medication. However, both tea and coffee contain hundreds of phytochemicals—including polyphenols, catechins, chlorogenic acids, lignans, and diterpenes—which plausibly account for potential systemic benefits and differences.
