Does fast food increase risk of depression in teens?

Fast food is a common element of many teenagers’ diets. This ubiquitous nature has frustrated pediatric providers fighting the tide of pediatric obesity, but a new small study from University of Alabama at Birmingham researchers indicates that another negative consequence could be an increased risk of depression.

The researchers looked at a sample of 84 younger teenagers who had an average age of 13.36 years and had participated in the Coping with Violence Study. The sample was 50% male and 50% female. It was also predominately African American, 95%. The sample was socioecomonically heterogenous, but had a significant number of low-income families, with an average annual income of $20,000 to $25,000. Average parental education was some college, but not degree. The teenagers were from 4 public middle schools in low-income, urban communities in Birmingham, Alabama. Free or reduced lunches were available to 83% to 87% of students at the schools included in the studies.

The 84 teenagers and their parents were interviewed by trained interviewers. Following the interview, the adolescents were instructed on how to perform a 12-hour overnight urine collection to measure sodium and potassium excretion and were scheduled to complete it in the following week. They were told to follow their typical diet and physical activity on the day when they collected the urine. The adolescents were told to record exact times of beginning and ending the urine collection. After roughly 1.5 years, 76 of the participants returned to participate in another interview wave. Depression symptoms from the 2 weeks before assessment were measured via the adolescents’ report of the Center for Epidemiological Studies Depression 10.

The researchers validated the creatinine, sodium, and potassium excretion values by comparing them to previous studies. They found that depressive symptoms were generally low and relatively stable over time (r = 0.49, P < 0.001), and at similar levels over time (paired t[74]=1.76, P = 0.082). Researchers found that greater sodium excretion was linked with more depressive symptoms in Wave 2 (r = 0.30, P = 0.009), but not at wave 1 (r=−0.09, P = 0.450). Older age at wave 1 was tied to more depressive symptoms at wave 2 (r = 0.24, P = 0.038). More advanced puberty development was correlated to great potassium excretion (r = 0.23, P = 0.042) and more depressive symptoms in wave 2 (r = 0.23, P = 0.048).

Researchers concluded that a diet high in sodium in sodium could contribute to developing symptoms of depression in early adolescence and that diet could be a modifiable risk factor for depression in adolescent patients. A focus on diet, in particular reducing sodium and increasing potassium, could improve overall mental health of adolescents.