When I wake up, the smell of freshly brewed coffee is about the most convincing argument to get up and start the day. Coffee is a favourite drink across much of the world, so it´s no wonder people are interested in its effect on health. Maja-Lisa Løchen from UiT The Arctic University of Norway in Tromsø has co-authored a study looking at associations between the method of brewing your coffee and serum cholesterol levels in over 20,000 Norwegians. (1)
Nicolle: Maja-Lisa, you have recently studied associations between coffee consumption and cholesterol levels in a large Norwegian cohort. Can you briefly tell us what's behind it?
Maja-Lisa: Coffee raises serum cholesterol because it contains diterpenes, such as cafestol and kahweol. The brewing method is the most important factor affecting the diterpene content. Boiled and plunger coffee contain higher contents of cafestol and kahweol than filtered coffee and while boiled coffee is associated with increased cholesterol, filtered coffee is not. This was first discovered in our Tromsø Study back in the 1980s. Espresso coffee has an intermediate cafestol and kahweol content, but less is known about its association with cholesterol. We had population data and wanted to investigate this in an adult population with mean age 56 years.
Nicolle: So how should I brew my coffee?
Maja-Lisa: If coffee makes you happy, brew it as you like it. If you prefer espresso or boiled and plunger coffee, you should be informed that it might increase your total cholesterol. We found that espresso coffee was significantly associated with increased total cholesterol, and a bit more in men than in women. I guess you are in your early 40s, and if you are healthy without any cardiovascular risk factors, I would try and limit the number of espresso cups to perhaps 3 cups daily. For filtered coffee there is no upper limit when we are talking about cholesterol.
Nicolle: But this is different in men, right?
Maja-Lisa: Yes, but again depending on their risk factors. We know that total cholesterol is a more important risk factor for myocardial infarction in men than in women and that this risk increase starts earlier in men than in women. Men in their 40s should know their risk profile and pay extra attention to their diet, including coffee consumption, if their total risk and cholesterol level is increased. Maybe one cup of espresso in the morning, and then switch to filtered coffee, would be my recommendation.
Nicolle: A potential link between coffee preparation and plasma cholesterol levels has first been hinted at in the 1980s and a number of studies have investigated whether and how coffee consumption is associated with mortality. It's good to hear that for most of us, drinking 1-3 cups of coffee per day rather reduces the risk for cardiovascular diseases and cancer. So how much is too much?
Maja-Lisa: Well, it is probably all in the brewing. Filtered coffee is associated with lower mortality than boiled coffee or no coffee at all, and non-filtered coffee is associated with increased CVD mortality once consumption reaches 9 cups a day. So, if you stick to a moderate amount (1-3 cups) of espresso or plunger, you are very safe.
Nicolle: And how much coffee have you already had today?
Maja-Lisa: I love coffee, so this morning I had one big cup of coffee (Norwegian size) brewed in my Italian mocca pot. I might drink another cup for lunch, otherwise I go for tea and water.
Nicolle: Thank you Maja-Lisa!