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In A Nutshell
- A 12-week study found that people who repeatedly ate the same foods lost more weight than those who varied their diets, averaging 5.9% body weight lost versus 4.3% for those who mostly logged unique items.
- Keeping daily calorie intake consistent from one day to the next was also linked to greater weight loss, with each additional 100-calorie swing in daily intake associated with roughly 0.6% less weight lost.
- Researchers suggest that eating routine meals may reduce the mental effort required to make food choices, making it easier to stay on track over time.
- The study was observational and small, with a sample that was 85% women, so results should be interpreted with caution until replicated in larger, more controlled experiments.
Could following a “boring” diet be best when it comes to weight loss? One study suggests that eating the same thing day after day might actually be the secret to shedding pounds.
Anyone who has ever packed the same turkey sandwich for lunch five days running knows the mild embarrassment that comes with it. A coworker glances over, raises an eyebrow, maybe cracks a joke about variety being the spice of life. Meanwhile, the person who spent 20 minutes that morning agonizing over a grain bowl recipe they found online has already blown past their calorie target before noon.
Monotony at mealtime carries a social stigma, signaling a lack of imagination, or worse, a lack of effort. Yet the boring eaters, it turns out, may have had an advantage.
New research published in Health Psychology offers evidence consistent with that idea. In a 12-week behavioral weight loss program, participants whose food logs included more repeated items lost more weight than those whose logs reflected a wider variety of foods. People whose entries were mostly repeats shed an average of 5.9 percent of their body weight, compared with 4.3 percent for those who logged mostly unique items. Even after accounting for how consistently people tracked their food, a factor that is itself one of the strongest predictors of weight loss success, dietary repetition still predicted greater weight loss.
How Repetitive Eating May Support Weight Loss
Charlotte J. Hagerman, a researcher at Drexel University’s Center for Weight, Eating, and Lifestyle Science and the Oregon Research Institute, led the study. Her team analyzed daily food logs from 112 adults with overweight or obesity enrolled in a structured weight loss program. Rather than asking participants to recall what they ate weeks later, a method prone to memory errors, the researchers used real-time entries from the Fitbit app, capturing nearly 90,000 individual food entries logged across three months after beverages and condiments were removed. It is among the first studies to examine the relationship between eating routines and weight loss using granular, day-by-day food log data.
All 112 participants were enrolled in a larger clinical trial testing different formats of behavioral weight loss treatment. Some attended weekly group sessions; others received a rotating mix of sessions, phone calls, and algorithm-guided messages. For this analysis, that distinction was set aside statistically so the team could focus on eating patterns alone. Everyone tracked their meals and snacks in the Fitbit app and weighed themselves daily on a study-provided wireless scale. To keep the data honest, participants had to have logged food on at least 75 percent of the study days, with a minimum of 800 calories recorded on each counted day. That cutoff was meant to filter out people who only bothered to track when they were eating well, which would have made their diets look far more consistent than they actually were.
From those logs, the team measured routine in four ways: how many of a person’s food entries were one-time items, how many foods showed up more than 10 times over the 12 weeks, how much a person’s daily calorie count bounced around from their own average, and how much their weekend eating diverged from their weekday eating. Beverages and condiments were stripped out beforehand so that a daily cup of coffee wouldn’t artificially inflate anyone’s repetition score.
The Numbers Behind the Boring Diet
After stripping out beverages and condiments, about 60 percent of all logged entries were foods that appeared more than once. Most participants weren’t eating an extremely monotonous diet, but they did have a core set of go-to items they returned to regularly. On both measures of dietary repetition, a consistent pattern emerged across the full sample, which lost an average of 5.6 percent of body weight over 12 weeks. People who ate more of the same foods lost more than that average, and those who varied their diets lost less. For every 10 percent increase in highly repeated items, weight loss was estimated to be about 1.6 percentage points higher.
Day-to-day caloric stability showed a similar association. Some participants stuck to roughly the same calorie count every day; others treated their daily target more like a weekly budget, saving calories for a weekend dinner out or allowing themselves the occasional off day. Greater consistency was linked to greater weight loss, and for roughly every 100 extra calories of daily swing, weight loss dropped by about 0.6 percent.
One result bucked the trend. Participants who ate somewhat more on weekends than weekdays actually lost more weight, not less. That contradicted the team’s hypothesis. The researchers offered a few possible explanations: weekend deviations in this group were modest, staying under 500 extra calories, which earlier studies had identified as the threshold where weekend splurges start hurting results. A small bump on Saturday may also have helped people feel less deprived, making it easier to stay disciplined from Monday through Friday.
Why Routine Might Make Dieting Easier
Habit formation science offers one possible framework for these results, though the study did not directly test the mechanism. When someone performs the same behavior in the same context repeatedly, eating the same breakfast at the same kitchen counter every morning, for instance, that behavior gradually shifts from requiring active decision-making to running on something closer to autopilot. Each novel food choice, by contrast, may require additional mental effort: weighing the caloric cost, logging a new item, recalculating the day’s totals. Over 12 weeks, those small costs compound in ways that are easy to underestimate.
There is also a simpler explanation rooted in how appetite works. Research has shown that eating a wide variety of foods within a single meal tends to drive people to eat more, because each new flavor resets the urge to keep going. Eating the same food repeatedly, by contrast, tends to dull its appeal over time. One earlier experiment found that adults with overweight or obesity who ate the same snack for eight weeks reported less craving-driven hunger than those who rotated through different snacks.
Caveats Worth Knowing
Because this was an observational study, it cannot prove that repetition caused the weight loss. People with stronger baseline self-discipline may have naturally gravitated toward both routine diets and more rigorous calorie restriction. The study also relied entirely on self-reported food logs, which are known to undercount actual intake. Additionally, the system counted a food as a “repeat” only when the logged name was an exact match, meaning someone who typed “grilled chicken” one day and “grilled chicken breast” the next would show up as eating two unique foods. That inexact matching likely nudged repetition scores lower than reality.
The sample was also small: 112 participants, roughly 85 percent of them women, with an average age of about 53. Whether the pattern holds for younger adults, men, or people outside a structured program remains to be tested. And critically, the measures of repetition didn’t account for what people were repeating. Someone eating the same grilled chicken salad every day and someone eating the same fast-food burger every day would look identical in this data.
Standard weight loss programs have long encouraged dietary variety, partly for nutritional balance and partly because counselors worry monotony will cause people to quit. Hagerman’s work doesn’t necessarily contradict the nutritional argument, but it does complicate the motivational one, suggesting that for at least some people, the mental relief of not having to decide what to eat may matter more than the excitement of a new recipe.
Disclaimer: This study observed associations between eating patterns and weight loss in a structured behavioral program; it did not prove that dietary repetition causes weight loss. Participants were predominantly middle-aged women enrolled in a formal clinical trial, so results may not apply to all populations. Always consult a qualified healthcare provider before making changes to your diet or weight loss plan.
Paper Notes
Limitations
The most significant limitation is the inherent bias in self-reported food logs, which tend to undercount actual intake. The researchers took several steps to reduce this bias, including using only the first 12 weeks of the program (when tracking adherence is highest), setting an 800-calorie minimum for a valid tracking day, and excluding participants who tracked fewer than 75 percent of days. Because missed tracking days are not random (people are less likely to log on days when they’re not sticking to their diet), the final sample may skew toward highly motivated participants, which could limit how broadly the findings apply. Measures of dietary repetition may also carry error, as the exact-match coding system would classify near-duplicate entries as unique foods, likely undercounting repetition. Because the study was correlational, causality cannot be assumed; pre-existing differences in self-regulation or motivation are a plausible alternative explanation. The sample was predominantly female (84.8%) and middle-aged (average age 52.6), limiting generalizability to other populations. Future research should use experimental designs in which participants are randomly assigned to repetitive versus varied eating patterns.
Funding and Disclosures
This research is a secondary analysis of data originally collected under a clinical trial funded by the National Institutes of Health’s National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK; R01DK12564). The secondary analysis received additional funding. The authors declare no conflicts of interest with respect to the research, authorship, or publication of this article. The study was reviewed and approved by Drexel University’s Institutional Review Board (Protocol Number: 2102008368). Deidentified data and analysis syntax are publicly available on the Open Science Framework at https://osf.io/rp325/.
Publication Details
Authors: Charlotte J. Hagerman, Asher E. Hong, Nicole T. Crane, Meghan L. Butryn, and Evan M. Forman. Hagerman is affiliated with Drexel University’s Center for Weight, Eating, and Lifestyle Science, the Department of Psychological and Brain Sciences at Drexel University, and the Oregon Research Institute in Springfield, Oregon.
Journal: Health Psychology, published by the American Psychological Association (ISSN: 0278-6133)
Title: “Do Routinized Eating Behaviors Support Weight Loss? An Examination of Food Logs From Behavioral Weight Loss Participants” | DOI: https://doi.org/10.1037/hea0001591 | Received: August 20, 2025 | Accepted: October 30, 2025
