A study conducted at the University of Navarra and Las Palmas de Gran Canaria University followed more than 12,000 people for six years and found that a diet high in trans fats correlates with a nearly 50 percent increased chance of developing depression.
Conversely, they found that individuals who consumed healthy amounts of olive and fish oils had a lower chance of developing the disorder.
At the beginning of the trial, researchers collected data regarding the volunteers' eating habits and general health. They determined that none of the participants had depression before the study began, while in the end 657 of them had developed depression.
Study authors said the healthier diet resembles that of people living in the Mediterranean region while eating patterns involving high levels of trans fat would be more common in Western areas, like the United States.
Trans fat is typically found in processed products with hydrogenated fats, like store-bought pastries and fast foods. The researchers found that the more trans fat a person consumed, the higher their likelihood of developing depression.
The authors also concluded that consumption of trans fat has a detrimental effect on cardiovascular health.