We’ve all experienced instant gratification from purchasing a new article of clothing. But then you remember the fashion industry is responsible for 10% of carbon emissions and 20% of industrial water pollution worldwide, and that cool shirt you just bought doesn’t seem nearly as cool anymore.

With the increased awareness amongst consumers of the environmental impacts of the fashion industry, the pursuit of a more sustainable system has only grown. There’s particularly been an emerging interest in alternative ways of consuming clothing, whether that’s buying secondhand or renting from a clothing rental service.

While these shopping habits seem better in theory, a number of components go into determining whether something is sustainable or not, from a company’s labor practices to the amount of water it uses in the manufacturing process. Today we’re focusing on the greenhouse gas emissions created through our most common shopping habits.

Emissions Created by Shopping Habits, Ranked from Best to Worst

Earlier this year, the journal Environmental Research Letters published a study that found some surprising data about different buying behaviors. The researchers compared the global warming potential (GWP) of a pair of jeans that was manufactured the same way in different scenarios: buying new, thrifting, renting, and reducing.

Below, we rank each shopping habit from best to worst, based on the emissions created through their life cycles.

1. Reducing

In the study, the scenario with the lowest global warming potential by far was reducing—aka the “extended use” of clothing. What is extended use, exactly? It’s simply using the clothes you already have in your closet for as long as you can.

The reason why reducing produced far fewer emissions than the other scenarios was because it was the only one that avoided the calculation of primary manufacturing. Even when accounting for all the times you would use and wash the pair of jeans, and the end of its life, the GWP was still drastically lower than other scenarios where the pair of jeans was recycled or thrifted. The most sustainable way of consuming fashion is not consuming at all.

2. Thrifting

When you do shop for clothes, thrifting—aka reusing—is the most eco-friendly option. When you buy used clothing, you’re not using any new materials. You’re also extending the life of a piece of clothing that would likely wind up in a landfill—especially considering a clothing item is only worn an average of seven times before it gets tossed out.

According to the Waste and Resources Action Programme, a 10% increase in secondhand sales could save 3% carbon, 4% water, and 1% waste per tonne of clothing. So before you head to TJ Maxx and scour the racks in search of the latest trends, consider heading to Goodwill instead. You’ll find unique pieces that not only help you develop your own personal style, but benefit the planet in the process.

3. New

Buying new clothing understandably results in more carbon emissions than buying used. Instead of buying a pre-loved item, each new item you hang up in your closet requires raw materials and plenty of the Earth’s dwindling resources.

According to The World Bank, it takes 3,781 liters of water to make just one pair of jeans, which ends up equating to 33.4 kilograms of carbon equivalent. If that’s just for one pair of jeans, you can imagine the toll all the clothing produced around the world each year has on the planet. (That’s an estimated 80 billion pieces annually, FYI.)

While buying new isn’t the most planet-friendly option, shopping better helps. Purchasing from sustainable companies that make high-quality and long-lasting clothing from responsibly sourced materials is a great place to start. Try to only purchase a new item if you know it will be in your life for years to come.

4. Renting

Clothing rental services are still fairly new, becoming more mainstream in recent years. While renting clothing has many advantages—like getting more use out of each clothing item, and preventing individuals from buying as much new clothing—it does have some downfalls in the sustainability department.

The main issue with renting lies with the transportation required to get these packages from point A to point B… then back to point A. Delivering and returning these clothing rental packages rack up more carbon emissions than any other clothing shopping option. Luckily, there are ways you can make your rental experience better for the planet.

Reducing the carbon impact of rental clothing can be done by getting as many wears out of your garments as possible before returning them, renting from a sustainable brand, renting only for certain occasions, and renting from companies that operate near you. Before you rent, do your research for the most sustainable fit.

The Takeaway

No shopping habit is perfect; there are always going to be downsides. Because of that, it’s important to really think about what you’re buying before going through with a purchase. Just because a thrift store is having a massive sale, for instance, doesn’t mean you should fill up your cart.

When you shop for clothes, only buy what you love and know you’ll cherish for years. Because as shown in this study, there’s no better option for the planet than buying less (and buying better).