Coffee Consumption Is Associated With Lower Liver Stiffness: A Nationally Representative Study

Background & aims: Coffee is associated with a reduced risk of liver disease. This association is limited by important sources of confounding such as recall bias, healthy user bias, and indirect measures of liver outcomes or health. We aimed to examine the impact of coffee consumption with liver fibrosis and steatosis in a nationally representative sample.

Methods: We evaluated 4510 subjects 20 years and older from the 2017 to 2018 National Health and Nutrition Examination Survey study who underwent both transient elastography and two 24-hour dietary recall examinations. We tested the associations between liver stiffness measurements (LSM) of 9.5 kpa or greater or controlled attenuation parameter (CAP) and coffee consumption. We used decaffeinated coffee and tea consumption as controls. As a sensitivity analysis, we included all drinks in 1 model, examined the impact of caffeine consumption, and adjusted for the Healthy Eating Index-2015 and sugar-sweetened beverage consumption as separate models.

Results: The study sample described was aged 48 ± 0.6 years, 73% were overweight or obese, 10.6% had diabetes, 47.5% reported participation in vigorous physical activity, and 23% drank 2 or more alcoholic drinks per day. After multivariate adjustment, there was no association between coffee and controls with CAP. Subjects who drank more than 3 cups of coffee, but not other drinks, had a 0.9 lower kPa (95% CI, -1.6 to -0.1; P = .03). More than 3 cups of coffee were protective for LSM of 9.5 kpa or higher (odds ratio, 0.4; 95% CI, 0.2-1.0; P = .05). Accounting for all beverages in the same model, only consuming more than 3 cups of coffee remained independently associated with LSM (odds ratio, 0.5; 95% CI, 0.2-0.9; P = .03). Caffeine was not associated significantly with LSM at any dose. Finally, adjusting for sugar-sweetened beverage consumption and Healthy Eating Index-2015, coffee consumption remained associated with a lower LSM. The protective nature of coffee consumption therefore is not attributable to caffeine and persists in participants regardless of their diet quality.

Conclusions: Coffee is associated with lower liver stiffness, but not steatosis, as measured by CAP among US adults.