The team found drinking caffeinated ground, instant or decaffeinated coffee could reduce risk of developing and dying from liver conditions, with the health benefit peaking at three to four cups per day.
"Coffee is widely accessible and the benefits we see from our study may mean it could offer a potential preventative treatment for chronic liver disease,” says lead author Dr Oliver Kennedy
“This would be especially valuable in countries with lower income and worse access to healthcare and where the burden of chronic liver disease is highest."
Researchers at the Universities of Southampton and Edinburgh began looking at data gathered from the UK Biobank study that followed 495,585 participants, over 10 years, to track any links between coffee consumption and liver complications.
Initial findings revealed 78% (384,818) drank caffeinated ground/instant or decaffeinated coffee, while 22% (109,767) did not drink any type of coffee.
During the research’s duration, the team noted 3,600 cases of chronic liver disease, including 301 deaths with 5,439 cases of chronic liver disease or steatosis and 184 cases of Hepatocellular carcinoma.
In contrast to non-coffee drinkers, coffee-drinkers had a 21% reduced risk of chronic liver disease, a 20% reduced risk of chronic or fatty liver disease, and a 49% reduced risk of death from chronic liver disease.
Kahweol & cafestol
Ground coffee appeared to be the most effective, with the research team attributing its effect to its high levels of Kahweol and cafestol, which have shown efficacy in chronic liver disease in animals.
“There is biological plausibility of a protective effect of coffee against CLD outcomes,” the team suggests.
“Alternative active ingredients in coffee may include chlorogenic acid, kahweol and cafestol, which protect against liver fibrosis in animal studies.”
“Kahweol and cafestol are present in highest concentrations in ground coffee, which was most protective,” the paper adds.
“Given the protective effects of the different coffee types with varying composition, there may be a complex relationship involving more than one active ingredient.”
Observational and laboratory studies suggest that consumption of coffee confers a protective effect against chronic liver disease and hepatocellular carcinoma.
This effect has been observed among drinkers of caffeinated and, to a lesser extent, decaffeinated coffee.
Coffee has been proposed as a potential intervention to prevent chronic liver disease onset and progression of hepatocellular carcinoma in at-risk patients.
However, the attributes of an effective coffee-based intervention remain uncertain in terms of quantity and preparation.
This would affect composition since decaffeinated coffee lacks caffeine, while filtered and instant coffee have only minimal amounts of kahweol and cafestol.
No accounting for changes
The team adds that coffee consumption was only reported when participants first enrolled in the study and did not account for any changes in the amount or type of coffee, they consumed over the 10.7-year study period.
As participants were predominantly white and from a higher socio-economic background, the findings may be difficult to generalise to other countries and populations.
Source: BMC Public Health
Published online: doi.org/10.1186/s12889-021-10991-7
“All coffee types decrease the risk of adverse clinical outcomes in chronic liver disease: a UK Biobank study.”
Authors: Oliver Kennedy et al.