42Young adults entering into college experience immense shifts in both personal and 43 professional environments and this may result in some of them experiencing a lot of 44 stress and difficulty in coping with their new surroundings. Such potentially stressful 45 events may trigger multiple psychological as well as physiological effects. The 46 current study investigated multiple psychological parameters such as PSS14 47 (Perceived Stress Scale), K10 (distress scale) and positive mood measures, along 48 with salivary cortisol levels, in a repeated measures longitudinal study of first year 49 students (~ 19 years of age) enrolled at a residential college in India. Six salivary 50 cortisol samples were collected over a one-year period from 20 students. On each 51 sampling day, a questionnaire designed to evaluate (K10, PSS14 and Mood) 52 psychological parameters was also administered. 53 Overall, men showed a significantly lower level of salivary cortisol compared to 54 women. Men also showed a decrease in perceived stress (PSS14) and distress 55 (K10) with time. However, women reported similar perceived stress and distress 56 levels all year round. Academic stress was reported by the students to be the most 57 important stressor, whereas financial stress was reported the least number of times 58 by all participants. Our results suggest that men seem to have a better capability to 59 adjust to the new environment of a residential program with time. In contrast, women 60 show an elevation in salivary cortisol at the end of the semester (the final 61 assessment stage) in spite of a continuous assessment curricular design. This study 62 not only provides an important glimpse into the sex differences in stress response in 63 the first one year of joining an undergraduate program, but it also provides a 64 valuable longitudinal dataset from the Indian undergraduate student cohort which is 65 lacking in literature.66 67 68 69 70 71 72 73 74 75 76 77 Keywords: psychological, student stress, academic stress, residential program, 78 gender differences, physiological 79 80 81 82 83 84 85 86 87 88 89 90 91Stress is any event that poses a threat or challenge to physical and mental wellbeing 92 of an individual (Lazarus and Folkman, 1984). Emerging adults starting college, face 93 stressful events such as coping with a new academic environment, relational 94 responsibility, future financial security and, searching for their own identity among 95 others (Kadison and DeGeronimo, 2004). Late adolescence is a critical age where 96 stressors can affect the physiology and psychology of individuals and risk 97 development of mental health issues in the future (Tennant, 2002). Early life 98 stressors can lead to the onset of anxiety symptoms (Breslau et al., 1997), 99 depression (Brown et al., 1996), schizophrenia (Patel et al., 2007) and even suicidal 100 tendencies (Wilcox et al., 2010). The major physiological reaction mechanism by