Medical students gain weight and lose exercise motivation during their first year despite maintaining stable eating habits, according to a 2026 longitudinal study of 87 first-year medical students. Gram Research analysis shows that stress—not lack of knowledge—drives these changes, with the biggest impacts occurring during exam periods. Students’ psychological well-being declined significantly over the academic year, suggesting that targeted stress management programs could help protect both mental and physical health during medical training.
According to Gram Research analysis, a new study tracked 87 first-year medical students throughout their entire academic year and found something surprising: even though these students are learning about health, they’re actually getting less motivated to exercise and gaining weight. Their stress levels went up and their overall happiness went down as the year progressed. The good news? Their eating habits stayed pretty stable, showing they have some built-in resilience. The research suggests that medical schools need to do more to help students stay healthy during their intense training, especially around exam times when stress peaks.
Key Statistics
A 2026 longitudinal study of 87 first-year medical students found that body mass index increased significantly over one academic year (p = 0.009), despite no measurable changes in actual exercise or diet quality.
According to research reviewed by Gram, motivation for physical activity declined significantly among medical students over the academic year (p = 0.020), even though the amount of exercise they reported remained stable.
A 2026 study of 189 medical students (87 who completed follow-up) found that perceived stress increased significantly during the academic year, with the largest impacts occurring during examination periods.
Research shows that psychological well-being declined across the academic year in medical students, with strong correlations found between stress levels and both physical activity engagement and diet adherence.
The Quick Take
- What they studied: How the stress and demands of medical school affect students’ exercise habits, diet, weight, and mental health over one full academic year
- Who participated: 87 first-year medical students (65% female, 35% male, average age 19.8 years) at a university in Rome, Italy who completed surveys at the start and end of the school year
- Key finding: Students’ weight increased noticeably, their motivation to exercise dropped significantly, and their stress levels rose—even though their actual eating habits stayed the same
- What it means for you: If you’re a medical student or in any demanding academic program, expect that stress and busy schedules will naturally reduce your exercise motivation and may cause weight gain. Being aware of this pattern helps you plan ahead with strategies to stay active and manage stress, especially during exam periods.
The Research Details
Researchers followed 189 first-year medical students at the start of the school year (November 2024) and checked in with them again at the end (June 2025). Of those students, 87 completed all the surveys both times. The students answered questions about their weight, how much they exercised, what they ate, how motivated they felt about exercise, how stressed they were, and how happy and healthy they felt overall.
The researchers used several well-established questionnaires that scientists use worldwide to measure these things. They measured stress using a standard 10-question stress scale, tracked diet using a Mediterranean diet checklist, and measured exercise using an international physical activity questionnaire. They also looked at motivation for exercise and overall well-being using validated psychological tools.
At the end, they compared the beginning-of-year answers to the end-of-year answers to see what changed. They used statistical tests to figure out which changes were real and not just random variation.
This study design is important because it follows the same students over time, which lets researchers see how medical school actually affects real people’s health and habits. Rather than just comparing medical students to other groups, this approach shows what happens to individual students as they go through the stress of their first year. This gives us a clearer picture of cause and effect.
The study had a reasonable sample size (87 students who completed both surveys) and used well-established, scientifically validated measurement tools that are used in research worldwide. However, the study only tracked students at one university in Italy, so results might be different in other countries or schools. Also, students self-reported their information rather than having researchers measure them directly, which means some answers might not be perfectly accurate. The study lost about 54% of participants between the start and end, which is a notable limitation.
What the Results Show
The most striking finding was that students’ body mass index (BMI, a measure of weight relative to height) increased significantly over the academic year. This wasn’t a huge change, but it was statistically significant, meaning it was real and not due to chance.
Surprisingly, the actual amount of exercise students did didn’t change much, and neither did their diet quality. However, something important did shift: students’ motivation and willingness to exercise dropped noticeably. This suggests that students weren’t necessarily exercising less because they didn’t know how or couldn’t access gyms—they were exercising less because they felt less motivated to do it.
The mental health picture was concerning. Students reported higher stress levels as the year went on, and their overall psychological well-being declined. These changes were most noticeable during exam periods, suggesting that academic pressure was the main driver. Students’ happiness and sense of well-being (measured by the WHO5 index) also showed signs of decline, though this was borderline statistically significant.
The study found strong connections between students’ mental health and their physical activity levels. Students who were more stressed and less happy were also less likely to exercise. Similarly, students who stuck with healthier eating patterns tended to have better psychological well-being. This suggests that diet and exercise aren’t just physical health issues—they’re deeply connected to mental health. The fact that students maintained stable eating habits despite increasing stress suggests they have some protective factor or routine around food that helps them stay resilient.
Previous research has shown that medical students worldwide experience high stress and often develop unhealthy habits. This study confirms those findings but adds new insight: the problem isn’t that students forget what they learned about healthy eating or suddenly can’t exercise. Instead, stress specifically reduces their motivation and willingness to be active. The weight gain finding aligns with other studies showing that high-stress periods often lead to modest weight increases, likely due to a combination of reduced activity and stress-related eating patterns.
The biggest limitation is that about half the students who started the study didn’t finish it, which could mean the results only reflect students who were more committed or healthier to begin with. The study only measured students’ self-reported information (what they said about themselves) rather than actually measuring their weight or activity with devices, so some answers might not be perfectly accurate. The study was done at one university in Italy, so results might be different in other countries or types of schools. Finally, the study couldn’t prove that medical school caused these changes—it only showed that changes happened during medical school. Other life events could have contributed.
The Bottom Line
If you’re a medical student or in a similarly demanding program: (1) Expect that your motivation to exercise will naturally decrease during stressful periods, and plan ahead with strategies to stay active anyway—like scheduling exercise with friends or setting up automatic reminders. (2) Protect your eating habits, which appear to be more stable than exercise motivation. (3) Actively manage stress through proven methods like exercise, meditation, or talking to counselors, since stress appears to be the main driver of negative changes. (4) Medical schools should consider adding built-in stress management and fitness support programs, especially around exam times. The confidence level for these recommendations is moderate to high, based on this study plus existing research.
Medical students should definitely pay attention to these findings, as should other students in high-stress academic programs (law school, graduate programs, etc.). Parents of students in these programs should also be aware that stress-related weight gain and reduced motivation are common and predictable. Medical educators and school administrators should use this information to design better support systems. People in other high-stress professions might also recognize these patterns in their own lives.
The changes in this study happened over one academic year (9 months). Weight gain was modest but measurable. Motivation changes and stress increases happened gradually throughout the year, with the biggest impacts during exam periods. If you implement stress management and exercise strategies, you might see improvements in motivation and stress levels within weeks, though weight changes typically take longer (several months) to reverse.
Frequently Asked Questions
Why do medical students gain weight if they’re learning about health?
A 2026 study found that stress reduces exercise motivation, not knowledge. Medical students maintained healthy eating habits but gained weight due to decreased physical activity motivation and stress-related changes, despite understanding health principles.
Does medical school stress affect mental health?
Research shows psychological well-being declined significantly in first-year medical students over one academic year, with increased perceived stress (p = 0.046) and worsening emotional health, particularly during exam periods.
Can medical students maintain healthy habits during their first year?
A 2026 study found that students maintained stable, healthy eating patterns throughout the year, suggesting diet is more resilient to stress than exercise motivation. This shows that protecting dietary routines can help maintain some health stability.
When is the best time to intervene with stress management for medical students?
Research indicates exam periods show the most dramatic declines in well-being and exercise motivation. Implementing stress management support specifically around high-pressure academic periods could prevent the worst health impacts.
What’s the connection between stress and weight gain in medical students?
A 2026 longitudinal study found that increased stress correlated with reduced exercise motivation and modest weight gain, even when eating habits stayed the same. Stress appears to reduce physical activity more than it changes diet.
Want to Apply This Research?
- Track weekly exercise motivation on a 1-10 scale alongside actual exercise minutes completed. This helps you notice when motivation drops before it affects your actual activity levels, giving you time to intervene with stress management or social support.
- Set up a ‘stress-proof exercise plan’ with a friend or accountability partner. During high-stress periods (like exam weeks), switch to shorter, more enjoyable activities rather than trying to maintain your normal routine. Log these modified workouts in the app to maintain the habit even when intensity drops.
- Create a monthly dashboard showing three metrics: perceived stress level, exercise motivation, and weight trend. This helps you see the connections between stress and your other health behaviors, making it easier to spot when you need extra support. Set alerts for when stress rises above your normal range so you can proactively increase stress management activities.
This research describes patterns observed in one group of first-year medical students and should not be considered medical advice. Individual experiences vary significantly. If you’re experiencing significant stress, weight changes, or mental health concerns, consult with a healthcare provider or mental health professional. This study shows associations, not definitive cause-and-effect relationships. Always discuss major lifestyle changes or health concerns with a qualified healthcare provider before making decisions based on research findings.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.