That free office coffee perk may come with a hidden cost: your heart health.

While there is plenty of research to support both the health benefits and some health risks in a daily cup of coffee or two, how it is brewed may make a big difference to your health.

The established health benefits include: reduced risk of type 2 diabetes,  lower risk of Parkinson’s and Alzheimer’s disease, improved liver health, possible reduction in risk of some cancers, antioxidant and anti-inflammatory effects. Some of the risks attributed to higher intake (4-5 cups daily) of coffee consumption can include: increased anxiety, disrupted sleep, digestive issues, elevated cortisol levels, and weight gain if consuming sweetened coffee.

A new study from Uppsala University and Chalmers University of Technology reveals that common workplace coffee machines—specifically brewing machines—may be exposing employees to substances that raise cholesterol levels. The culprits? Cafestol and kahweol, two naturally occurring compounds in coffee known to increase LDL ("bad") cholesterol.

Researchers analyzed 14 different coffee machines and found that those lacking fine paper filters, like many popular workplace brewers, produced the highest concentrations of these cholesterol-elevating diterpenes.

“Most of the coffee samples contained levels that could feasibly affect LDL cholesterol and cardiovascular risk,” said Dr. David Iggman, lead researcher at Uppsala University.

With many organisations leaning on free coffee to sweeten the return-to-office deal, this study raises important health considerations. According to Flavia’s 2023 data, over 80% of employees said free beverages would make them feel more valued, and two-thirds say coffee is their go-to drink to start the workday.

The study’s bottom line: filtered coffee is the safer bet. Machines that use paper filters—like traditional drip brewers—can almost entirely remove harmful diterpenes.

“Drip-filter coffee, or other well-filtered coffee, is preferable for people who drink a lot of coffee daily,” Iggman advised.

Cafestol and kahweol concentrations in workplace coffee compared with conventional brewing methods.

Extract from Dexter Tilo article | Business Strategy | April 3, 2025

Being aware of how your home or office coffee machine works to filter your coffee could be worth investigation if your cholesterol levels are important to you?

While this research is interesting and certainly worth consideration, lifestyle research conducted in so call “Blue Zones” such as Ikaria, Greece where the locals drink Greek coffee, which is boiled in a briki (a small copper pot) and not filtered appears to contribute to improved longevity given the high concentration of centenarians in this population.

So before you pour your office coffee down the sink, consider finding a lot more peer reviewed research to support such a decision.