You maybe aware that I am a coffee fan. Big fan.
I was a bit concerned to come across a Mayo Clinic Proceedings article showing an increased risk of death in younger people drinking coffee.
This topic is a matter of hot debate and is not settled.
This is certainly an important debate as coffee consumption is a big deal in the world and in America (and I do not want to give up my cup of Joe).
(Yes, I am biased. Let’s move on.)
The National Coffee Association National Coffee Drinking Study estimates that 64% of Americans drink coffee.
About 3.1 cups of coffee per day on average.
A News cast I caught featured an interview with a popular health figure (guru) who is not to hot on coffee.
He referenced this Mayo Clinic article as a source further confirming that coffee is bad.
Science is challenging and complex and does not lend itself to news bites well. There was no debate about it.
Coffee is bad.
I was skeptical of his conclusion.
I have discussed coffee previously and its role with potential benefits of weight loss. There are thousands of chemicals and antioxidants in coffee and whether these chemicals are healthy or harmful has been a matter of debate for some time.
I found the study he referenced and digested it.
The study from the Mayo Clinic Proceedings involved 43,727 participants who were observed from 1971 to 2002. They were questioned and examined. Labs were obtained including blood sugar. Height and weight were measured. Even a graded exercise test was completed.
A statistical analysis was used to determine association with coffee consumption and all-cause mortality as well as disease-specific mortality.
They found that coffee was harmful.
At least that coffee may cause increased mortality in the younger folks under 55 years of age.
Younger men who drank coffee consuming 8 to 14, 15-21 and more than 28 cups per week were at higher risk of all-cause mortality compared to those that did not consume any coffee.
Also, younger women (<55 years of age) who consumed over 28 cups of coffee per week were also associated with increased risk of all-cause mortality.
Coffee consumption was NOT found to increase risk of all-cause mortality in older men or women (greater than age 55 years).
An editorial also posted in the Mayo Clinic Proceedings rebuked the findings and argued that the study did not adjust for important confounders:
Coffee consumption may be a marker of less-healthy food consumption, unmeasured and not addressed by Liu et al. For instance, how often did people’s cups of coffee accompany servings of doughnuts, bagels, toast and jam,or other refined and sugary foods? And how often did people drink their coffee with sweetened creamer or added sugar?
I would agree.
Ultimately, the study cannot prove that coffee consumption is the culprit. No observational study can.
Coffee is consumed in a variety of ways, including highly fattening and sugary frappes.
Today’s coffee is much different than yesterday’s coffee. Maybe this is why the older group showed no association with increased death.
My grandpa lived to 92.
He drank it black . . . all day long.
- Liu, et al. Association of Coffee Consumption With All-Cause and Cardiovascular Disease Mortality. Mayo Clinic Proceedings, 2013.
- DiNicolantonio, et al. Is coffee harmful? Looking for longevity, say yes to the coffee, not the sugar. Mayo Clinic Proceedings, 2014.
- Liu, et al. In reply—Is Coffee Harmful? If Looking for Longevity, Say Yes to the Coffee, No to the Sugar. Mayo Clinic Proceedings, 2014.
Image Credit: Coffee by Jen on Flickr