The study period to become a medical professional is notoriously stressful This label can be attributed to various factors like long tedious training, social expectations, long work hours, high liability, sleep deprivation, and a constant lack of time to relaxin this vulnerable area, physical appearance, either weight loss or obesity, can affect the mental health of these young people.

To determine the role of body mass index (BMI) on the levels of perceived stress in medical students.

Our study was descriptive and analytical cross-sectional, carried out with medical students in the faculty of medicine of sfax (Tunisia) during October 2022.

An anonymous survey was asked to the students.

Data collection was done by a self-administered questionnaire via Google Forms administered in the students’ Facebook groups. The questionnaire was composed of a part for the collection of socio-demographic data and a psychometric scale:

• - Cohen’s Perceived Stress Scale (PSS) to determine the level of stress

A total of 95 responses was collected.The average age of our sample was 25.8±3.4 with female predominance (78,9%).

The half of the population (53,7%) were residents in medicine.

The majority of them (88,4%) had an average socio-economic level and singles (83,2%) .

81,1% had a stressor related to studies in 50,5%,to family in 40 % and financial in 9,5%.

Tobacco consumption were reported by 14,7 % .

A psychiatric history was reported by 17.9% of the students, 76.5% of whom are anxiety disorders.

27.4% tried to control their weight. Several methods of weight control were used, the most frequent (65.4%) was diet, none resorted to laxatives and 8.4% consulted a nutritionist.

Almost half of the population (57,9%) slept between 5 and 7 hours.

The average body mass index was 23.64 kg/m2 (SD=3.53).

According to PSS scores, 21.1% of students had severe level of stress, 69.5% had moderate stress level while 9.5% had low level of stress.

Those followed in psychiatry had a higher level of stress (p<10-3), especially those with anxiety disorder (p=0,02).

The students pressed for weight control were more stressed than their peers.

The levels of stress were higher among underweight students (BMI < 18.5) and overweight students (BMI >25) without significantly correlations.

The current study revealed that medical students, especially underweight or overweight students, are more susceptible to develop stress symptoms,that is why psychic support must be available on their university.

None Declared