Tea and coffee are luxury goods. They are not necessary for our survival, but many of us could not live without our daily dose of steaming caffeine. Tea is the second most consumed beverage after water and coffee is not far behind – we drink billions of these beverages every day.

Human civilization is steeped in both drinks. Coffee traces its origins to 9th-century Ethiopia, where legend has it that a goat herder named Kaldi accidentally discovered the energizing action of coffee berries. Tea has its roots in ancient China, where the mythical figure Shen Nong is said to have been accidentally poisoned and saved by a tea leaf falling into his mouth.

Both addictive beverages eventually reached Europe in the 17th century and became the drink of choice in coffeehouses and teahouses, where intellectuals of the time met to discuss the issues of the day. Such was the popularity of these “drug foods,” as they are known, that their trade helped expand empires.

Nowadays, they are intensively cultivated, processed, packaged and transported around the world, leaving their mark on the environment in the process.

What factors affect the environmental footprint?

The impact of these drinks can vary depending on several factors. But there is some research that looks at the entire life cycle of both products – from cultivation and transport to consumption and waste. The findings highlight that agriculture has the greatest environmental impact.

“Of course, every farm is different,” said Amy Stockwell, a life cycle analyst who has spent 18 years researching coffee. “They are grown in different countries. Weather conditions are different. Farmers treat their crops differently.”

But the industrialization of tea and coffee harvesting, irrigation and fertilizers, which emit nitrous oxide, a powerful greenhouse gas, contribute to the effect on the climate. Coffee, for example, was traditionally planted in the shade of other trees. It is now largely grown in vast plantations exposed to the sun, which requires more intensive use of water, fertilizers and pesticides.

Deforestation for plantations a critical factor

“Much of the deforestation that occurs in the countries of the Global South serves the production of crops, such as coffee, black and green tea, for export to countries of the Global North, such as Germany,” said Lena Parts, professor of comparative politics with a focus on environment, climate and global supply chains at the Free University of Berlin.

Tea leads to deforestation in countries like Sri Lanka and India. But coffee’s link to deforestation is particularly well documented, with around 130,000 hectares of trees disappearing each year to make way for plantations, according to the Coffee Barometer 2023. A study by Wageningen University in the Netherlands estimates that 5 % of deforestation can be attributed to coffee.

Products must also be processed to be consumed. The environmental impact here depends on the type of energy used – fossil fuels or renewable energy sources.

Transfer follows. While estimates for tea and coffee differ, one determining factor is whether the product is transported by sea or air. A 2021 study found that switching from airplane to cargo ship significantly reduced transportation emissions.

The packaging also leaves its mark. The impact depends on whether it is plastic, paper from sustainable sources or recyclable. But the packaging also has its positives. It reduces food that ends up in landfills, where it rots and emits the greenhouse gas methane. Coffee waste is a big challenge, says Stockwell.

“How often do we make a whole pot of coffee and then only drink half of it? I’ve seen some evidence in the past that usually a third of a pot of coffee is wasted,” Stockwell said.

So what is better, tea or coffee?

Well, it’s complicated. It’s hard to compare a kilo of tea to a kilo of coffee and make firm recommendations because, as with any “agricultural product, there’s a huge range of variety,” says avid tea drinker Stockwell.

But researchers looking at the carbon footprint of a cup of tea versus a cup of coffee – without sugar or milk – say the former “wins”, simply because we use less product per cup. A tea bag contains about 2 grams of leaves and a cup of coffee uses about 7 grams of beans.

If we add milk to the equation, coffee gets a worse score. Cow’s milk has a large carbon footprint and we tend to add more of it to coffee – think ‘lattes’ and ‘flat whites’.

“When you drink your coffee and tea, actually the biggest decision you make is what milk you put in it,” said coffee aficionado and UCL professor Mark Mazlin. So switching to plant-based milk or drinking coffee or tea plain is a convenient solution.

How to reduce the environmental impact?

“Heating only the amount of water you need is very important,” Stockwell says. “I always fill the kettle more than I should. And of course, then I use all the extra electricity to heat more water than I’m going to use.”

Other small improvements include storing produce in airtight containers to stop it going stale, and buying loose leaf tea instead of tea bags, which often contain plastic so can’t be composted.

Businesses, farmers and governments also have a role to play. UCL’s 2021 study on coffee found that using less fertiliser, managing water and energy more efficiently and exporting the beans by cargo ship instead of aeroplanes, can reduce the crop’s carbon dioxide emissions by around 77% .

What do businesses owe?

Businesses can also use more environmentally friendly packaging and renewable energy sources where possible. And some companies have signed up to voluntary schemes to ensure their supply chains are sustainable. Last year, the European Union passed legislation requiring businesses to prove that products such as coffee and cocoa do not come from deforested land.

This is important because coffee consumption is predicted to double in the next 25 years. At the same time the world is warming and the area suitable for growing coffee will be halved. Coffee is a sensitive crop.

“He’s a bit like us. You know, we like to be nice and warm. We like some tolerable humidity. We don’t want a lot of heat and humidity,” Mazlin says, adding that we need to ensure that “as the demand for coffee and tea increases, we don’t resort to deforesting new areas for that production.”

Edited by: Kostas Argyros