Drink coffee from the office machine every day? Researchers have a warning

For many people, coffee from the office machine is part of the daily routine. One cup when you arrive, another after lunch, perhaps one more to get through the afternoon. It is convenient, familiar and rarely something you think twice about.

But if you drink several cups a day, there may be another reason to pay attention to how your coffee is prepared.

The difference isn't necessarily how strong the coffee tastes or how much caffeine it contains. It comes down to something in the beans that can end up in your cup, depending on the brewing method.

The coffee oils that can affect your cholesterol

Coffee contains two naturally occurring oily compounds called cafestol and kahweol. These substances can raise LDL cholesterol, often referred to as “bad” cholesterol, which is associated with a higher risk of cardiovascular disease.

The Dutch Voedingscentrum explains that the more effectively coffee is filtered, the fewer of these cholesterol-raising substances make it into the drink.

Caffeine isn't responsible for this particular effect. Decaffeinated coffee can contain similar amounts of cafestol and kahweol, so switching to decaf alone won't necessarily make a difference.

What Swedish researchers discovered

In a 2025 study, researchers tested coffee from 14 office machines in Sweden. They compared it with coffee made using other methods, including paper filters.

They found that coffee from certain office machines contained around 15 times more cafestol than paper-filtered coffee. Cafestol is a natural oil in coffee that can raise LDL, or “bad” cholesterol.

Not all office machines were the same, though. The amount of cafestol varied from one machine to another, so this doesn't mean every office coffee contains high levels.

The researchers also estimated that swapping three cups of office-machine coffee for paper-filtered coffee each workday could lower LDL cholesterol. But this was a calculation based on a model, not a result measured in people during a clinical trial.

What newer guidance says about coffee and heart health

The Swedish study isn't the only reason to pay attention to how you brew your coffee. In July 2026, the American Heart Association published an overview of the latest evidence on coffee and heart health.

It highlighted the difference between filtered and unfiltered coffee. Cafestol, the compound found in higher amounts in some brewing methods, can raise LDL cholesterol. Paper-filtered coffee allows much less of this substance to reach your cup.

This doesn't mean coffee is automatically bad for your heart. The important point is that how you prepare it can affect its impact on cholesterol. And if you drink several cups every day, those small differences may be worth considering.

Which brewing methods are better?

The Voedingscentrum's guidance offers a useful comparison:

• Lowest levels: Paper-filtered coffee, coffee pads, instant coffee and percolator coffee.
• Moderate levels: Espresso, capsule coffee and moka-pot coffee.
• Highest levels: French press or cafetière coffee, Scandinavian boiled coffee, and Turkish or Greek coffee.

The reason is filtration. Paper filters trap much of the coffee oil before it reaches your cup. With a French press, the metal mesh allows more of these substances through.

Office coffee varies, too. Some machines use paper filters or filtered coffee concentrates, while others brew coffee in ways that leave more oils in the drink. If you're unsure how your workplace machine works, its supplier may be able to tell you.

Do you need to change your coffee habit?

The Dutch guidance recommends no more than two to three cups a day of espresso, capsule coffee or moka-pot coffee because of their moderate levels of cholesterol-raising substances. It advises avoiding cafetière and boiled coffee where possible, or limiting them to one cup a day.

If you drink several cups at work, switching to paper-filtered coffee is one practical change to consider, especially if your LDL cholesterol is elevated.

You don't necessarily need to give up coffee. Just remember that the brewing method can matter as much as the beans you choose.