Diet Linked to Better Mental Health for Kids

A new study finds that children who have healthy diets are more likely to be happy, and children who are happy are more likely to have healthy diets.

Overweight and Obesity

As we seek to understand more about the relationship between a child’s diet and their overall mental health, one thing to keep in mind is our culturally informed understanding of weight. In the U.S. and in many countries of the global north, there is a propensity to associate better health with smaller overall body mass, with the exception of extremely low body mass or very high muscle mass. The correlation, however, is not a direct one, and factors like exercise, lifestyle, and diet need to also be considered when painting a complete picture of overall health.

The social pressure to maintain a certain body shape is one of the reasons why kids who are overweight or obese are at higher risk for mental health problems. Currently 1 in 3 children in the United States are either overweight or obese, and worldwide rates of obesity have risen 10 fold since 1975.

This epidemic is a global one: The Harvard School of Public Health explains:

“Fueled by economic growth, industrialization, mechanized transport, urbanization, an increasingly sedentary lifestyle, and a nutritional transition to processed foods and high calorie diets over the last 30 years, many countries have witnessed the prevalence of obesity in its citizens double, and even quadruple. Rising prevalence of childhood obesity, in particular, forebodes a staggering burden of disease in individuals and healthcare systems in the decades to come.”

diet and mental health in kids: current research

While overweight and obesity is a risk factor for a host of chronic physical diseases, it is also a risk factor for mental health problems. Perhaps unsurprisingly, children who are overweight are more prone to low self-esteem, negative body image, and depression. Due to the gravity of the issue, so much of the research on this topic is focused on understanding how both becoming and being overweight is connected to children’s mental health.


One such study is the Identification and Prevention of Dietary- and Lifestyle-Induced Health Effects in Children and Infants (IDEFICS). As its title indicates, the aim of the study was to understand the factors that contribute to childhood obesity and develop strategies for prevention. The study surveyed more than 16,000 children ages 2 to 9 across eight European countries: Belgium, Cyprus, Estonia, Germany, Hungary, Italy, Spain and Sweden. As reported on the website: “The study measured weight status and related health outcomes such as blood pressure and insulin resistance, direct behavioral determinants such as physical activity and diet, and indirect determinants such as social/ psychological factors and consumer behavior.”

At the start of the study, parents completed a questionnaire that detailed how often specific foods were eaten each week. There were 43 food items to choose from in total. From this information, every child was assigned a Healthy Dietary Adherence Score (HDAS). The HDAS score captures information about the child's adherence to a healthful diet, taking into account behaviors such as avoiding sugary and fatty foods and eating fresh vegetables and fruit.

Children's well-being was assessed at the start and end of the 2-year trial period and included information regarding self-esteem, emotional problems, and relationships with parents and peers. Height and weight were also captured at the start and end of the study. When all of the data was collected, researchers from many different countries and universities conducted their own analyses to try and understand the interplay between diet and wellness in children.


A research team from the Sahlgrenska Academy of the University of Gothenburg in Sweden used data from the IDEFICS study to analyze the connection between weight and psychological well-being in children. This particular analysis included 7,675 children from the original study and the findings were recently published in the journal, BMC Public Health:

"We found that in young children aged 2–9 years, there is an association between adherence to healthy dietary guidelines and better psychological well-being, which includes fewer emotional problems, better relationships with other children, and higher self-esteem, 2 years later," says corresponding study author Dr. Louise Arvidsson. The study showed that healthy diets led to increased overall well-being in children.

The authors also reported that higher levels of self-esteem at the start of the study were associated with a higher HDAS after 2 years, and that the associations between Healthy Dietary Adherence Score (HDAS) and well-being were not affected by the child's weight, which was unexpected.

“It was somewhat surprising to find that the association between baseline diet and better well-being 2 years later was independent of children's socioeconomic position and their body weight."

This is somewhat surprising given the social stigma surrounding body mass, yet it also goes along with the understanding that health and wellness incorporate so many different factors, weight just being one of them.

So what constitutes a healthy diet?

The study showed that 2–3 portions of fish per week was associated with better self-esteem, as well as no emotional problems or issues with peers. Consuming wholemeal products was also linked with an absence of peer problems. And these associations went in both directions. For instance, children with a better sense of well-being ate fruits, fats, and sugars in line with recommendations, and those with better self-esteem had lower sugar intakes.

As other researchers have suggested, emotions can regulate eating and eating can regulate emotions. This is related to the saying “you are what you eat,” in the sense that mood and food are often reflections of each other.

While these findings are significant and warrant additional inquiry, researchers identify clear limitations of the IDEFICS study:

  • Study was observational and relied on self reported data —> less reliable reporting

  • High drop out rates among children with poorer diets and lower self- esteem —> makes drawing definitive conclusions more difficult as data sets are incomplete


Dr. Arvidsson notes that "[t]he associations we identified here need to be confirmed in experimental studies including children with clinical diagnosis of depression, anxiety, or other behavioral disorders rather than well-being as reported by parents."

While the IDEFICS study is significant, particularly for identifying eating patterns among healthy children, more objective, quantitative analysis is needed to determine the relationship between mood and food in children.

Do you have or know of children who struggle with mental health problems related to diet or weight? What are the tools you use to support their overall wellbeing and how do you see this phenomenon being addressed in your own communities?