Love eating late at night? Scientists have news to share

We have all been there, feeling peckish long after dinner. Whether it’s a packet of chips in front of the television, a chocolate bar after dinner or a raid on the fridge before bed, plenty of people enjoy a late-night snack.

But scientists investigating this everyday habit have found something about eating late at night that could make you think twice before reaching for your next bite.

What researchers discovered about eating late at night

Researchers at Oregon Health & Science University in the United States analysed data from almost 200 000 people to see whether eating late at night was linked to liver disease.

The study drew on three long-running research projects: the Nurses’ Health Study, the Nurses’ Health Study II and the Health Professionals Follow-up Study.

The researchers examined participants’ reported eating habits and health outcomes over a median follow-up period of 16 years.

They found that people who reported eating late at night had a higher risk of two liver conditions: metabolic dysfunction-associated steatotic liver disease (MASLD), commonly known as fatty liver disease, and cirrhosis, which involves serious scarring of the liver.

Their findings, published in Clinical Gastroenterology and Hepatology, showed an association between late-night eating and a 20% to 30% higher risk of liver disease compared with not reporting this eating habit.

The researchers defined late-night eating broadly as eating after dinner or after bedtime. The study did not establish a specific cut-off time that applies to everyone.

Eating late at night: Why the timing of meals could matter

The timing of meals may matter because the body operates according to a natural 24-hour cycle known as the circadian rhythm.

This internal clock helps regulate sleep, hormones and metabolism. The liver also follows these rhythms, which influence how the body processes nutrients.

Dr Andrew McHill, an associate professor and sleep and circadian physiologist at Oregon Health & Science University, said previous research had found that eating during the biological night could reduce the body’s ability to metabolise food efficiently.

Disruptions to the body’s normal rhythms have also been linked to metabolic problems, including obesity and diabetes.

Researchers are now investigating whether meal timing could also influence liver health, potentially offering another way to address health risks without necessarily changing what people eat.

Should you stop snacking before bed?

The findings do not mean that everyone who eats an evening snack will develop liver problems.

Fatty liver disease can range in severity, and only a small proportion of people with the condition develop serious complications such as cirrhosis.

Lead researcher Dr Robert Wilechansky, a liver specialist at Oregon Health & Science University, suggested that limiting calorie intake in the hours before bedtime might be beneficial.

But there is still more work to do before researchers can establish whether changing meal times actually improves liver health.

One limitation is that the study relied on participants reporting eating habits and medical diagnoses. Although the researchers accounted for several other factors, an observational study cannot establish cause and effect.

The participants were also drawn from three specific research cohorts in the United States of America, so the findings may not apply equally to every population.

Researchers are now recruiting participants for further clinical research to investigate whether eating earlier can improve measures of liver health in people with existing fatty liver disease.

For now, the study adds to growing evidence that the timing of everyday habits may matter for long-term health.