The relationship between body size and depression symptoms in adolescents

To evaluate the relationship between body size and depressive symptoms, as well as the moderating effects of age, sex, and socioeconomic status (SES), in a sample of young adolescents.

The study group comprised 678 young adolescents (age 11 to 14 years). Body mass index (BMI) z scores were used to estimate body size. Depression symptoms were assessed using the Children's Depression Inventory (CDI). The spline function was used to examine the shape of the relationship between BMI z score and depressive symptoms.

In the total sample, CDI scores were lowest for BMI z scores between -1 and -0.5. CDI scores increased progressively for BMI z scores > 0. In boys, CDI scores increased for BMI z scores > 2, whereas in girls, CDI scores increased for BMI z scores > -0.5 and < -1. Age did not have a significant moderating effect. SES had a moderating effect only in boys (P = .011).

The relationship between body size and depressive symptoms in young adolescents is curvilinear and is moderated by sex. Heavier-than-average and underweight girls, as well as obese boys, had the highest depression scores.