The American Heart Association says adults can safely drink up to five cups of coffee per day and regular consumption may improve cardiovascular health.

A caffeine calculator

This simple calculator takes your preferred caffeinated drink and your body weight to determine how much is the right amount, and how much might kill you. In case you've ever had the morbid curiosity about just how much of that tea you'd have to drink to doze off forever. Find out your moderate and lethal doses here, as well as some extra info on caffeine consumption.

Understand distinctions between coffee types and other popular cafe beverages with this visual guide.

Up to 400 milligrams of caffeine a day is considered safe

Small, frequent doses can be more effective than large amounts, though caffeine can raise blood pressure and heart rate, especially in people with hypertension. While low doses of caffeine may help with depression by stimulating dopamine, excessive caffeine, particularly from energy drinks, can lead to anxiety and heart issues.

Coffee is, indeed, addictive

Caffeine enters the brain through the bloodstream, where it blocks receptors that cause us to feel tired and enables stimulants like dopamine to increase alertness and focus. Over time, the brain begins to expect this level of stimulation, and caffeine addiction can develop. Caffeine withdrawal causes headaches, irritability, and fatigue.

Coffee is, generally, good for your health

While overconsumption certainly has its drawbacks—hello, not sleeping until the sun rises—on the whole, coffee is fine, even beneficial, for your health. It can even help prevent serious health conditions, like heart attacks and liver cancer.

Coffee gives you energy, but it ultimately makes you more tired

The caffeine in coffee delays your brain's fatigue signals. Caffeine blocks adenosine, a compound that builds up as you burn energy and signals rest. Once caffeine wears off, adenosine floods back, leaving you even more tired.

Coffee is made by brewing the seeds from the coffeea plant

The cherries from the coffeea plant are milled into coffee beans. After processing, the beans are dried and roasted.

High-frequency sound waves have been used to brew espresso with room-temperature water and about one-fourth the energy of a traditional espresso machine, which relies on hot water and pressure.

In the 1600s, coffee had religious significance

In the 1600s, coffee was important in multiple religious traditions. In Yemen, it was the drink of choice for Sufi mystics to improve their focus and fuel their grueling meditations. Pope Clement VIII's approval spread coffee’s popularity from the Muslim to the Christian world, paving the way for the cappuccino.

A cup of coffee on Earth contains about 100 proton masses worth of dark matter

The estimate is based on Earth's location within the Milky Way and the dark matter cloud it resides in. Because scientists do not know the nature of dark matter, the mass may be accounted for with any number of dark matter particles of varying mass.

Most coffee is grown within the coffee belt, a geographic region characterized by mild climates, regular rainfall, and higher altitudes.

Civet coffee is some of the most expensive (and bizarre) coffee in the world

Known colloquially as "cat poo coffee," the style is made from beans that have been consumed and then excreted by the Asian palm civet, a small mammal related to the mongoose. Coffee made from these beans is said to be smooth and complex, with notes of chocolate.

Visualize how Coca-Cola's secret formula has changed over time

Coca-Cola contained small amounts of cocaine until the early 1900s—but that's not the only time Coca-Cola has altered its recipe over the years. For instance, Coca-Cola transitioned from cane sugar to high-fructose corn syrup in the 1980s.

See how much daily sugar substitute intake the FDA considers to be safe

The agency states in this PDF graphic that a person weighing about 132 pounds would have to consume roughly a couple dozen sweetener packets daily—or more—to reach unsafe levels of consumption. The accumulated consumption would be across all sources, including diet beverages, sugar-free candies, and actual packets added to coffee.

Coffee production took off in the 1800s

Coffee production in South America took off in the 1800s, with Brazil establishing itself as the largest global producer in the 1840s. Today, the country grows over one-third of the world's beans and consistently leads in global coffee production, with other Latin American countries like Colombia and Guatemala.

The history of coffee

From its likely origins in what is now Ethiopia to today's worldwide consumption, this video uses a map to show how coffee conquered the world. Follow along and see how pilgrimages and centuries of trade influenced the spread of the beverage we all know so well.

Chocolate can be deadly in humans, but only after consuming extraordinary quantities

Based on tests with mice, the lethal dose of chocolate is estimated to be no more than 1,000 mg/kg. This means that the lethal dose of dark chocolate for the average US adult is about 6.5 kilograms (14.33 pounds), or about 8,300 Hershey's kisses, in one sitting.

Why coffee prices have reached record highs in 2026

Coffee beans reached $9.46 per pound in February 2026, according to the Bureau of Labor Statistics, the highest price since the Bureau began tracking the price in 1980. Experts blame bad weather in Brazil and Vietnam (the world's largest producers) and heightened US tariffs.

European colonization contributed to coffee's spread

European colonization created channels for large-scale coffee exports with workforces based in Asia, Latin America and the Caribbean. Trade routes throughout the Middle East and the rest of the world carried the drink to new shores and changed the agricultural and economic landscapes of the countries in the Bean Belt.

Coffee brewing likely originated in Ethiopa and the Arabian Peninsula

A mixture of merchants and colonialism then launched the drink across Europe and the New World. Many European coffee traditions, like the Viennese custom of serving it alongside a small cup of water, are remnants of how coffee has been prepared in the Middle East for centuries.

Before it was a drink, coffee was used for handwashing.

Bees are more likely to remember a flower if its nectar contains caffeine

Plants want pollinators to keep coming back, so the finding suggests that some plants, such as Citrus and Coffea species, have evolved to include caffeine in their nectar. Researchers suggest the findings could help develop methods to reinvigorate pollinator populations.

Coca-Cola made up roughly 19.2% of US carbonated soft drink market share as of 2023

Separately, Diet Coke made up about 7.8% of US market share that year. Pepsi was responsible for 8.3% of market share, as was Dr. Pepper.

Your DNA may determine whether you like coffee or tea

Whether people prefer coffee or tea may boil down to a matter of taste genetics. People with a version of a gene that increases sensitivity to the bitter flavor of caffeine tend to be coffee drinkers, according to a report. Read on for more.

Cultivate your coffee taste with this interactive flavor wheel

Coffee is one of the more complex things humans consume, and taste can vary drastically based on bean genetics, roasting technique, and more. Using this flavor wheel, you can more accurately describe your coffee's aroma by starting from the center and moving outward.

Differences in the ratio of sugars help distinguish Mexican and American Coke

Mexican Coke is sweetened with cane sugar (sucrose), which dissolves into equal amounts of fructose and glucose, whereas American Coke, which uses high-fructose corn syrup, contains more fructose than glucose.

The WHO labeled aspartame as 'possibly carcinogenic' but US regulators consider it safe

The International Agency for Research on Cancer, an arm of the World Health Organization, labeled aspartame—the artificial sweetener in Diet Coke—as one of several hundred possible cancer-causing substances in 2023. The determination was based on animal and human studies and "limited" evidence linking it to liver cancer. The WHO and US Food and Drug Administration both say the substance is safe at moderate levels. The FDA says a person weighing about 132 pounds would need to have 75 packets daily to reach an unsafe level.

Different brewing methods require different grinding methods

With so many brewing methods—AeroPress, Moka Pot, and French press to name a few—knowing the right grind size for your coffee beans is essential. Danish coffee expert Asser Christensen, also known as the Coffee Chronicler, explains how grinding works and recommends the best grind choice for different coffee makers.

Why Coke tastes different at McDonald's

Fans of the sugary soda Coca-Cola have noticed significant differences between its canned variety versus what pours forth from the fountain at McDonald's. Is there anything to the claim? Weird History Food takes a dive into this essential fast-food...

John Pemberton only sold roughly 25 gallons of Coca-Cola syrup in its first year

That equates to roughly 9 drinks per day. But once he brought it to pharmacies that hooked the syrup up to their soda fountains, sales increased significantly, with roughly 2,000 gallons being sold two years later. This video about Coca-Cola's early history is narrated by actress Jenny Slate for a Comedy Central series called "Drunk History," so not all of it is intended to be entirely factually accurate.

Soda is one of the most overpriced items at restaurants

All restaurant food is marked up—that's how they turn profits, after all—but soda is one of the most egregious. Fountain soda is remarkably cheap, with restaurants often paying a few cents for each glass before selling it for a few dollars. Food publication The Takeout estimates that the typical markup is around 1,000%.

Distinct plant species evolved to produce caffeine as a pesticide

Although it provides a defense against insects trying to eat caffeine-bearing plants, the molecule is an example of exaptation, where its original function was repurposed over time. Studies show that some plants now produce caffeine-laced nectar to help pollinators move more quickly and pollinate more efficiently.

Beanless 'coffee' is an eco-friendly alternative

As we consider the role of agriculture in climate change, many people are seeking alternatives to the most resource-hungry crops—coffee included. Are new synthetic alternatives the answer? Startups are exploring beanless “coffee” made in a variety of ways.

Slow pour-over coffee resists the haste of 'espresso' and commodification of drip

Pour-over coffee involves what its name suggests: slowly pouring hot water from a gooseneck kettle over a funnel of ground coffee, usually requiring at least 3 minutes. This trend developed in the 1970s in opposition to on-demand drip coffee and "espresso," literally invented as an "express" option to save time.

A historical deep dive into everything coffee

Can't get enough coffee? Join documentarian James Harper and historian Jonathan Morris for an immersive dive into the history of everyone's favorite beverage. From the highlands of Ethiopia to the streets of Vietnam to Viennese cafes, you'll travel with the humble coffee bean as it spreads across the globe.

A world-famous barista's primer on coffee appreciation

If you think you can tell good coffee from bad but don’t know how to put the distinction into words, world-famous barista Nicole Battefeld-Montgomery is here to help. Her instructions for breaking down a cup of coffee rivals any sommelier’s wine-tasting guide.

After the Boston Tea Party, colonists switched to coffee, which became the main morning drink for revolutionaries.

After the Boston Tea Party (1773), colonists boycotted tea and turned to coffee, with coffeehouses becoming hubs for revolutionary discussions. The stimulating import from the Caribbean helped shape the nascent American taste.

Unlike its Mexican counterpart, American Coca-Cola contains high-fructose corn syrup rather than sugar

There are a few reasons why American Coke turned away from sugar in the 1980s, but none of them are related to consumer health. This Reader's Digest article breaks down the history behind Coke's recipe change, explaining why the company continues using high-fructose cough syrup.