Reviewed by John M. Grohol, Psy.D. on April 2, 2012
The findings reveal that consumers of fast food are 51 percent more likely to develop depression than minimal or non-consumers.
Furthermore, the connection between the two is so strong that “the more fast food you consume, the greater the risk of depression,” said Almudena Sánchez-Villegas, Ph.D., lead author of the study.
The results also showed that those participants who ate the most fast food and commercial baked goods were more likely to be single, less active and have poor dietary habits (eating less fruit, nuts, fish, vegetables and olive oil). It was also common for individuals in this group to smoke and work over 45 hours per week.
The results were equally consistent in regard to the consumption of commercial baked goods. “Even eating small quantities is linked to a significantly higher chance of developing depression,” said Sánchez-Villegas.
The study sample consisted of 8,964 participants who were part of the SUN Project (University of Navarra Diet and Lifestyle Tracking Program). The subjects had never been diagnosed with depression or taken antidepressants. They were assessed for an average of six months, and during this time, 493 were diagnosed with depression or had started to take antidepressants.
This new data supports the results of the SUN project in 2011, which recorded 657 new cases of depression out of the 12,059 people analyzed for over six months. This study showed a 42 percent increase in the risk of depression associated with fast food, which is a lower percentage than found in the current study.
Sánchez-Villegas said that “although more studies are necessary, the intake of this type of food should be controlled because of its implications on both health and mental well-being.”
Previous studies suggest that certain nutrients play a preventative role in depression. These include B vitamins, omega-3 fatty acids and olive oil. And an overall healthy diet has been linked to a lower risk of developing depression.
This study has been published in the Public Health Nutrition journal.