November 25, 2025
4 min read
‘Saving Room’ for a Big Thanksgiving Dinner Can Be Bad for Gut Health
Skipping meals before a big holiday feast probably isn’t the best idea for gut health, experts say. Here’s how to prevent overeating on an empty stomach—and tips for if you do
Jonathan Knowles/Getty Images
To savor every delectable Thanksgiving dish, it might be tempting to “save room” in your stomach before the big event by skipping breakfast or lunch. But gut health experts say eating little to nothing all day and then consuming a massive meal—particularly a rich and heavy one—can be taxing on the tummy.
“It’s very common that people talk about saving room for special meals or holiday meals, and certainly on Thanksgiving,” says Kathryn Tomasino, a psychologist who specializes in gastrointestinal health at Northwestern University. But fasting before a hefty meal “can have some negative consequences, both for people with gastrointestinal conditions and general digestion.”
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How Fasting Affects Gut Hormones
Scientists can glean some insight into what happens to the gut during these big meals by extrapolating data from fasting research. Normally when people eat regular meals throughout the day, consuming food triggers a cascade of different hormones that signal hunger, aid digestion, manage blood sugar levels and cause satiety or fullness.
“It’s a beautifully orchestrated system,” says Janice Jin Hwang, chief of the division of endocrinology and metabolism at the University of North Carolina School of Medicine.
True fasting, which many researchers define as 10 hours or more of not eating anything, causes shifts in that process. Hwang explains that the fasting body essentially prepares to take in more nutrients once you resume eating again: The gut may experience systemic pains—better known as “hunger pangs.” Gastric muscle movements increase to help move and digest food faster. Brain circuits involved with desire and motivation for food become activated, ultimately influencing the way people approach their next meal behaviorally and psychologically, Tomasino says.
“If you are fasting all day and then you go to have a big meal, you may feel like your eyes are bigger than your stomach,” she says.
People may build their plates differently as a result. They’re more likely to choose highly palatable foods that have more fat and sugar. After a day without eating, the brain is more drawn to these kinds of energy-rich foods, Tomasino explains. It’s also common to eat more quickly on an emptier stomach, which can cause people to ingest more air and become bloated. And eating quickly might mean chewing less thoroughly, leading to larger chunks of food that are more difficult to digest.
“You’re also not taking the time to allow those digestive processes to send signals to the brain the way they typically would because everything’s happening so quickly, so it’s very easy to become overly full,” Tomasino says. “You know—that ‘got to unbuckle my belt’ feeling.”
Being stuffed is not only physically uncomfortable; too great a volume of food in the gut can lead to gastric reflux and regurgitation. Down the line, being overly full can cause poor sleep, abdominal pain and disrupted bowel movements. Skipping meals in an attempt to be more calorie- or weight-conscious also tends to backfire because of this overeating behavior, Tomasino adds.
Hwang suspects most healthy people can likely adapt to the occasional big swing between fasting and eating a large meal. But suddenly devouring a massive meal that’s high in carbohydrates might cause issues for people with diabetes or obesity, however. “Sometimes there can be a little bit of a mismatch, and your body might produce more insulin than it needs or less,” which could lead to dangerously low or high blood sugar levels, respectively, Hwang says.
Tomasino generally doesn’t recommend the practice of fasting before a feast for anyone, regardless of health status.
“From a health perspective, I don’t think it’s a great choice to skip meals in lieu of having a really big meal later, because you’re not actually ‘saving room,’” Tomasino says. “If you’re eating breakfast, most of that food is going to leave your stomach well before you’re going to have another meal four to five hours later.”
Eating Holiday Meals Mindfully
Tomasino and Hwang do have some tips to protect your gut health while still allowing people to enjoy a delicious spread. Research has shown that the order in which you eat the foods on your plate can influence how your body processes the meal, Hwang says. A small 2015 study in Diabetes Care found that when people with type 2 diabetes ate the same meal twice on different days, eating the carbs first resulted in higher glucose levels than eating the protein and vegetables first.
“So if you haven’t eaten in a while and all of a sudden you eat a lot of carbs, that’s going to be broken up much more quickly into glucose and stimulate more insulin than if you eat a meal that has more fat or more protein or more fiber that’ll be digested a little bit more slowly,” Hwang says.
If you do wind up gobbling up too much turkey and pumpkin pie after not eating all day—perhaps by forgetting to eat during the preparation or festivities—Tomasino and Hwang say to try not to stress or feel ashamed. Tomasino recommends aiding digestion with some physical activity, such as cleaning up or going on a walk with family.
“If you do overindulge, try not to beat yourself up,” Tomasino says. “Give yourself that grace to have a little bit of fun on Thanksgiving.”
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