Eating too much junk food can affect your mental as well as your physical health, according to the latest research.
A study published in the Public Health Nutrition Journal found that people who regularly eat fast foods such as hamburgers, hotdogs and pizzas are 51 percent more likely to develop depression compared with those who eat little or none.
The risk of depression was linked to the amount of junk food consumed.
“The more fast food you consume, the greater the risk of depression,” said study leader Dr Almudena Sánchez-Villegas from the University of Las Palmas de Gran Canaria.
People who ate the most of this type of food were more likely to be single, less active, eat less fruit, nuts, fish, vegetables and olive oil and work more than 45 hours a week, the study found. They were also more likely to smoke.
The study included 8,964 people who had never been diagnosed with depression or taken anti-depressant medication. The scientists assessed the mental health and diet of the participants for an average of six months. At the end of the study period, 493 people were diagnosed with depression or had started taking anti-depressants.
The researchers also added that the link between commercial baked goods and depression was as “equally conclusive” as that seen with fast food. “Even eating small quantities is linked to a significantly higher chance of developing depression,” said Dr Almudena Sánchez-Villegas.
A previous larger study, published in the journal PLoS One, linked eating fast food with a 42 per cent increased risk of depression. Others studies suggest that certain nutrients, including group B vitamins, omega-3 fatty acids and olive oil may help to protect against depression. A Mediterranean diet has also been linked to a lower risk of developing the condition.
Dr Sánchez-Villegas concluded: “Although more studies are necessary, the intake of this type of food should be controlled because of its implications on both health (obesity, cardiovascular diseases) and mental well-being.”