Frequent coffee, herbal tea intake linked to lower levels of liver stiffness
Researchers observed an association between more frequent coffee and herbal tea consumption and lower liver stiffness measurements, according to a recently published study.
“Coffee and tea are the most consumed beverages worldwide and emerging as promising nutraceuticals for liver health. Consumption of these nutraceuticals has been associated with lower all-cause and cause-specific mortality, presumably through reducing the risk of features of the metabolic syndrome,” Louise J.M. Alferink, MD, from the Erasmus MC University Medical Center, Rotterdam, Netherlands, and colleagues wrote. “This large population-based cohort study shows an inverse and independent association between coffee and herbal tea consumption and log-transformed [liver stiffness measurement].”
The researchers employed data from the Rotterdam Study, a large ongoing population-based cohort study. Overall, 2,424 participants met their inclusion criteria. All participants completed a food frequency questionnaire. Mean age was 66.5 years, 57% were women and mean BMI was 27.2 kg/m2. Median liver stiffness measurement was 4.7 kPa (range, 3.8-5.8) and 125 had measurements of 8 kPa or higher, suggesting fibrosis. Thirty-two participants reported no coffee or tea consumption.
Of the 2,258 participants who consumed coffee, mean consumption was 2.6 cups per day and frequent consumers were proportionally more overweight or obese, younger, men, white, had a higher education level, more were current or past smokers, had lower prevalence of lipid disorders and more had type 2 diabetes.
Median consumption by the 2,052 participants who consumed tea was 1.2 cups per day (range, 04.-2.7) and frequent consumption was associated with women, less excessive alcohol use, fewer smokers, lower BMI and fewer features of metabolic syndrome. Participants reported consuming black tea (64.2%), herbal tea (36.3%) and green tea (26.1%).
Compared with participants with liver stiffness measurements below 8 kPa, participants with liver stiffness of 8 kPa or higher more often drank no coffee (10.4% vs. 6.7%; P = .006) or up to three cups per day (38.4% vs. 28.3%; P = .006), but fewer drank three or more cups per day (65.1% vs. 51.2%; P = .006).
Compared with no coffee consumption, the researchers found an inverse association between coffee consumption and liver stiffness measurements of 8 kPa or higher (OR = 0.87; 95% 0.46-1.64), particularly after adjusting for energy intake, age, sex, BMI, steatosis status, alanine aminotransferase, excessive alcohol use, current or former smoker status, soda consumption, DHDI, physical activity, total tea consumption and cream and sugar use in coffee (OR = 0.75; 95% CI, 0.33-1.67).
By the same comparison, participants with liver stiffness measurements of 8 kPa similarly drank no tea or up to three cups per day among the three tea categories, but those with higher measurements drank less herbal tea than those with lower measurements (27.2 vs. 36.8; P = .035), which remained significant after adjusting for energy intake and coffee consumption (OR = 0.61; 95% CI, 0.4-0.94).
In total, 34.6% of the participants had steatosis, though the rate was higher among participants with liver stiffness measurements of 8 kPa or higher (60% vs. 33.2%; P < .001) and differed among participants who consumed no tea (42.7%), up to three cups of tea per day (35.4%) and three or more cups per day (28.6%; P < .001).
Though not significant, the researchers found that participants who consumed three or more cups per day compared with less coffee consumption were less likely to have liver stiffness measurements of 8 kPa or higher among those with no steatosis (2.5% vs. 4.4%) and those with steatosis (6.9% vs. 13.1%).
“Mechanisms through which coffee and herbal tea promote liver health are unclear. Also, it is not known if these two beverages act through similar pathways. However, our data suggest that both have inhibitory properties for fibrogenesis and not steatogenesis,” the researchers concluded. “We found a protective association between coffee and liver stiffness that not only occurs in disease-specific settings but appears also to be present in the general population with and without steatosis. Since coffee is an accessible and relatively inexpensive beverage, it could be further implemented as a preventative strategy if future studies were to confirm our findings.” – by Talitha Bennett
Disclosure: The researchers report no relevant financial disclosures.