A new study says eating junk food is not only bad for your waistline but also for your mental health.
British and French scientists analyzed food and mood data from 3,486 men and women (average age 55) working in a London office, reports MSNBC.com.
Each person filled out a food frequency questionnaire that asked how often they had eaten a specific portion size of food during the previous year, with answers ranging from 'never' to 'six or more times a day.'
Two dietary patterns were determined: the 'whole food pattern' (a high daily intake of healthy fruits, vegetables and fish) and the 'processed food pattern' (noshing on lots of sweetened desserts, chocolates, fried food, processed meat, refined grains, high-fat dairy products and condiments).
Five years later, the same participants filled out a questionnaire that measured symptoms of depression.
After taking into account factors like age and sex, the researchers found that high consumption of the processed foods was more likely to lead to depression, while people who ate healthier were least likely to be depressed.
"Our finding shows a strong association between diet and depressive symptoms after controlling for a large range of socio-demographic factors, and for health behaviors such as smoking, physical activity, and health status," the New York Daily News quoted the study's author, Tasnime Akbaraly, as saying.
"The effect of diet on depressive symptoms didn't go down after we adjusted for other indicators of a healthy lifestyle, such as smoking, physical activity, and body mass. What we found isn't a spurious association," Akbaraly added.
The study has been published in The British Journal of Psychiatry.