Relationship Between Salivary Cortisol, Self-Assessed Stress Levels, and Body Mass Index in High Achieving High School Adolescents

Abstract

Studies of stress and cortisol levels in adults indicate that keeping normal levels of cortisol is beneficial to subjects. The hormone cortisol has many functions including proper glucose metabolism, regulation of blood pressure, immune function, and inflammatory response. When cortisol levels spike, as with stress, there can be a negative effect on the individual. Due to the hectic pace of modern life, the body’s stress response does not always have time to return to normal, leading to cortisol levels remaining too high. This can lead to suppressed thyroid function, blood sugar imbalances, higher blood pressure, lowered immunity, and increased abdominal fat. Stress plays a prominent role in the lives of millions of people all across the globe. This problem is not one that affects solely the adult population but also a multitude of adolescents and children. Oftentimes, stress can have both a physical and psychological effect on an individual. Many persons report an effect on food consumption when under stressful situations, causing one to either eat more or less than normal. In turn, these eating patterns can potentially influence the Body Mass Index (BMI) of an individual. While increased stress can lead to a higher or lower than normal cortisol level and BMI in adults, the role in adolescents is not entirely clear. This study investigated whether there is a relationship between stress and BMI in high-achieving adolescents, aged 14 to 18. The Perceived Stress Scale survey paired with additional questions that helped determine variables believed to impact stress levels were administered to determine overall stress levels in each subject. To determine cortisol levels, a competitive enzyme immunoassay was used. This study indicates that there are no significant correlations between perceived stress levels, salivary cortisol levels, and BMI in this group of individuals. However, a distinct difference in self-assessed stress levels was apparent between males and females. Somewhat unexpectedly, a negative relationship was found between BMI and salivary cortisol levels and perceived stress and salivary cortisol levels.