Are six small meals better than three big ones? A new study has surprising answers

We’ve all heard the advice: “Eat small, frequent meals to keep your metabolism going and manage hunger.” But is this popular belief actually backed by science? A new study by Drs. Zhang and Neuhouser at the Fred Hutchinson Cancer Center and partner institutions suggests otherwise. In fact, eating more often might not help you feel fuller and may even interfere with your body’s natural hunger cues. In the Frequency of Eating and Satiety Hormones study (FRESH), researchers wanted to see how eating more or fewer times a day affects hunger and fullness; not just how people say they feel, but also what’s going on inside their bodies, hormone-wise.

They recruited fifty healthy adults for the study and asked them to follow two different meal plans. One plan had them eat three meals a day, the way many of us grew up eating. The other plan broke the same amount of food into six smaller meals spread across the day. The key detail here is that the type and amount of food stayed exactly the same in both plans. Only the timing changed. Each person tried both eating patterns for 21 days, with a break in between. On the final day of each phase, participants came into the clinic for a full day of testing. On the final day of each phase, blood samples were collected every hour for six hours to measure appetite-related hormones. Participants also rated their hunger and fullness levels throughout the day.

The results were pretty interesting and surprising. When people ate just three meals a day, their hunger and fullness signals were more distinct. Ghrelin, the hormone that makes us feel hungry, spiked before meals and dropped afterward — which is what you’d expect if your body is clearly responding to meals. Likewise, the hormone PYY, which signals fullness, rose after meals and then gradually dropped. People also said they felt truly hungry before meals and full after.

But when those same people ate six times a day, their hormone levels showed much smaller fluctuations. Ghrelin levels rose only slightly between meals, and PYY increased only modestly after eating—much smaller shifts compared to the larger fluctuations seen with three big meals. In short, their bodies didn’t seem to recognize the small meals as clearly. Their hunger and fullness ratings showed the same trend: they felt kind of hungry or kind of full most of the day, but never really one or the other.

What’s more, these effects were even stronger for people with higher body fat or BMI. In this group, the body’s response to frequent meals was even more dulled. This suggests that people who struggle with energy balance may be more vulnerable with appetite regulation if they choose to have smaller, frequent meals throughout the day

These findings challenge the long-held belief that more frequent eating is automatically better. In this study, eating three times a day actually seemed to help the body better recognize hunger and satisfaction, which could help prevent overeating in the long run. Of course, everyone’s body is different. Some people may feel better with more frequent meals due to medical conditions, blood sugar issues, or just personal preference. But if you’ve been forcing yourself to eat six times a day because you thought it was the “healthy” thing to do, this research offers a good reason to listen to your own hunger cues instead.

This study was supported by the National Cancer Institute and the National Institute of Diabetes and Digestive and Kidney Diseases. The research was conducted at the Fred Hutchinson Cancer Center in collaboration with The Ohio State University and the University of Washington. The Fred Hutch Prevention Center Shared Resource was used for the study.

Fred Hutch/UW/Seattle Children’s Cancer Consortium member Dr. Marian Neuhouser contributed to this work.

Zhang X, Perrigue M, Schenk JM, et al. Objective and subjective appetite measures: high versus low eating frequency in a randomized crossover clinical trial. Obesity (Silver Spring). 2025; 33(5): 879-891.