Ultra-processed food increases depression likelihood among Korean women, study flags

01 May 2023 --- A Korean-based study has found a link between depression and a higher intake of ultra-processed food (UPF) among the female population. Females who consumed the highest measured level of UPF have a 1.51 times higher likelihood of suffering depression than those following a diet high in fruits and vegetables and lower in saturated fat, sugar content and dietary sodium levels, researchers discovered.

In Korea, depression rates between 2016 and 2020 among women were at 5.9% versus men at 3.04%, and the Korean average percentage of energy intake from UPF items was 27.49%. The study involved 9,463 adults.

The authors note that UPF consumption has increased globally because of its affordability and convenience. Depression is the most common mental illness worldwide and its link needs to be investigated, urge the researchers. Also, the depression rate is higher overall in females (14.4%) than in the whole population (12.9%). 

UPF disturbs the balance in the gut microbiota, causing dysbiosis, which affects the gut-brain axis.Mental health and diets
Published in Nutrients, the study could not confirm a link between UPF and depression among the 4,200 male participants, although a significance was found between smokers and diabetics with depression. 

However, among the 5,263 females, a significance was found between the likelihood of depression following a high UPF diet. The study also adjusted for body mass index, alcohol intake, smoking, hypertension, physical activity and diabetes.

The Korean-based researchers also point to previous studies that link factors of UPF to adverse mental health effects, such as the lack of bioactive micronutrients – minerals and vitamins – as limited in whole food constituents from fruits and vegetables. Therefore, the link to depression might be explained by a micronutrient deficiency. 

Additionally, UPF disturbs the balance in the gut microbiota, causing dysbiosis, which affects the gut-brain axis, directly reduces the production of serotonin and other neurotransmitters and drives inflammation, the authors argue.

“Food additives for flavoring, coloring, palatable enhancers and emulsifiers, or byproducts and contaminants in the production of UPFs may induce detrimental effects by disrupting endocrine signals or homeostatic regulatory pathways,” the study reads.Lately, debates have been taking place on whether the conception of UPF being unhealthy is valid.

Discussions on UPF
Last week, an expert panel gathered to discuss UPF and its misconceptions regarding if UPF is always considered less healthy, claiming that food is always processed and that we process food ourselves at home when we cook it.

Gert Meijer, chair at the European technology platform Food for Life, told NutritionInsight that the missing consumer trust has arisen from a lack of transparency from the food industry on how products are made and argued that buying a frozen pizza is as healthy as making a pizza at home.

“We are totally to blame as the food industry because we are working behind closed doors for factories to make our products,” Meijer told us. 

Last year, two contradicting studies were published in Great Debates in Nutrition, one evidencing the increased risks of morbidity and disease correlated with ultra-processed foods and another which argues that this food type may not be as bad as expected.

Additionally, recent research published in the American Journal of Preventive Medicine argued that 57,000 premature deaths in Brazil in 2019 were attributed to consuming UPF, making it 10% of all premature and preventable deaths in the country that year.

By Beatrice Wihlander