New Delhi, March 22 : Love to sip that freshly brewed coffee at work? Beware, your coffee brewing machine at the office may raise your cholesterol levels, claims a study.

The study led by researchers from the Uppsala University and Chalmers University of Technology in Sweden found that automated coffee brewing machines in the workplace contain natural chemicals, known as diterpenes -- known to increase cholesterols.

Elevated cholesterol levels are an established risk factor for cardiovascular diseases.

In the paper, published in the journal Nutrition, Metabolism and Cardiovascular Diseases, the team found significantly higher levels of cafestol and kahweol in coffee examined from 14 machines in Swedish healthcare facilities.

Cafestol and kahweol are coffee-specific diterpenes -- known for their potential to increase cholesterol levels.

The diterpene concentrations in coffee from brewing machines considerably exceeded paper-filtered coffee. It is because paper filters typically trap these compounds, but metal filters found in many coffee machines allow them to pass into your cup.

The researchers examined brewing machines -- which produce coffee in 10-30 seconds by passing hot water through ground beans and a metal filter; liquid-model machines -- which mix liquid coffee concentrate with hot water; and instant machines.

While the brewing machines showed the highest diterpene levels, the liquid-model machines generally contained much lower levels comparable to paper-filtered coffee.

For espresso, there was a considerable and unexplained variation in diterpene concentration between the four samples tested. This needs further study but may be of importance for regular espresso consumers, said the team.

'Based on the concentrations of cafestol and kahweol in investigated machine coffees, thoroughly filtered coffee seems like the preferable choice for cardiovascular health. Accordingly, filtered coffee should be preferred, also in workplace settings,' said the researchers.

'Intake of insufficiently filtered coffee during working hours could be an overlooked factor for cardiovascular health due to its effect on plasma cholesterol concentrations,' they added.

The researchers also acknowledged major limitations such as its small sample size and lack of details regarding the designs of each coffee machine. The team also called for establishing the link with more studies.

/IANS