"We know the liver is very much in tune with the body's circadian rhythms," Wilechansky said. "So we're interested in changing the timing of eating in a way that could make a difference in health without changing the composition of what people eat."

Co-author Andrew McHill, an associate professor and sleep and circadian physiologist at OHSU, said the findings fit a broader pattern in circadian research. "We are seeing over and over again that the timing of behaviors, whether it's sleep, eating or exercise, really matters," he said.

"For example, we have shown that eating during the night, when the internal biological clock is promoting sleep, reduces the ability of your body to metabolize foods as efficiently and can eventually lead to obesity, diabetes and now poor liver health," McHill said.

Animal studies support this line of thinking, McHill noted. Among the body's organs, the liver appears to be one of the most susceptible to mistimed eating relative to sleep.

The stakes are considerable. Fatty liver disease affects as much as 30% of the U.S. population, Wilechansky pointed out, and night shift workers — whose day-night cycles are chronically misaligned — already show elevated rates of obesity and heart disease.

How worried should late-night snackers be?

The researchers urge some perspective. "It's important to remember, of the people who developed fatty liver disease, only a small fraction develop serious forms of the condition like liver cirrhosis," Wilechansky said.

"Even so, the big takeaway here is that confining your calorie intake to several hours before bedtime might be beneficial," he added.

The study also has real limitations. It is observational, meaning it can show an association between late eating and liver disease but cannot prove that one causes the other. And the eating data were broadly defined and self-reported, which leaves room for error in how participants characterized their habits.

What comes next?

Wilechansky is part of an OHSU team now recruiting for a clinical study that will monitor eating behaviors directly, rather than relying on self-reports. That study will test whether shifting meals earlier actually improves clinical measures of underlying fatty liver disease.

Until those results arrive, the current findings offer a starting point rather than a definitive answer. "Our findings add to the growing body of literature linking late-evening eating patterns to adverse metabolic and liver outcomes," the authors write.

Previous research has already tied late-night snacking to heart disease and obesity; the new work extends that concern to the liver.

In addition to Wilechansky and McHill, the study's co-authors include Kevin Casey, Andrew Chan, and Tracey Simon of Massachusetts General Hospital in Boston. The paper, "Late-Night Eating is Associated with MASLD and Cirrhosis," appears in Clinical Gastroenterology and Hepatology (2026), DOI: 10.1016/j.cgh.2026.09.047.