Researchers from Oregon Health & Science University and Massachusetts General Hospital have found that people who reported eating late at night had a 20 to 30% higher risk of liver disease than those who did not.
Reaching for a snack after dinner or before bed may carry a cost beyond extra calories. Image credit: Jill Wellington.
“Night shift workers grapple with misalignment of the body’s natural day-night cycle, with elevated rates of obesity and heart disease,” said Dr. Robert Wilechansky, a hepatologist at Oregon Health & Science University.
“With as much as 30% of the U.S. population affected by fatty liver disease, we wondered whether small changes in timing meals might make a difference.”
“We know the liver is very much in tune with the body’s circadian rhythms.”
“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.”
In the study, the authors focused on two conditions: metabolic dysfunction-associated steatotic liver disease (MASLD), a buildup of fat in the liver formerly known as nonalcoholic fatty liver disease, and cirrhosis, a severe scarring of the organ.
They drew on three large, existing health surveys: the Nurses’ Health Study, the Nurses’ Health Study II and the Health Professionals Follow-up Study.
They extracted the diet and lifestyle habits that nearly 200,000 participants had reported, sorted them by eating behaviors and then looked for links to reported cases of MASLD or cirrhosis.
They found a 20% to 30% increase in both forms among the group of people who reported late-night eating compared to those who did not.
The findings add to a growing body of evidence that the body’s circadian rhythm, its internal 24-hour clock, plays a significant role in overall health.
Because the study relied on participants’ own reports of their habits, it shows an association rather than proof that late-night eating causes liver disease. Other factors, such as overall diet quality, weight and sleep patterns, may also play a role.
“We are seeing over and over again that the timing of behaviors, whether it’s sleep, eating, or exercise, really matters,” said Dr. Andrew McHill, a sleep and circadian physiologist at Oregon Health & Science University.
“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.”
The results appear in the journal Clinical Gastroenterology and Hepatology.
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Robert M. Wilechansky et al. Late-Night Eating is Associated with MASLD and Cirrhosis: The Nurses’ Health Study and Health Professionals’ Follow-Up Study. Clinical Gastroenterology and Hepatology, published online October 10, 2026; doi: 10.1016/j.cgh.2026.09.047
