Unhealthy eating may trigger eating disorders, affect brain health

A study using data from the longitudinal IMAGEN adolescent cohort sheds light on the association between eating behaviours and eating disorders (EDs) and brain maturation.

A total of 996 participants (52 percent women) with completed Three-Factor Eating Questionnaire scores at age 23 years and at least one measure from the Strengths and Difficulties Questionnaire available at ages 14, 16, 19, and 23 were included. Three distinct eating groups were identified: healthy eaters (HEs; n=423), restrictive eaters (REs; n=324), and emotional and uncontrolled eaters (E/UEs; n=249). [Nat Ment Health 2025;3:58-70]

Uncontrolled eating refers to eating in response to food palatability, social cues, and hunger, leading to eating episodes, while emotional eating pertains to eating episodes elicited by negative affect. The researchers noted that both are associated with increased susceptibility to EDs, hedonically driven food choices, higher BMI, and obesity.

Compared with HEs, REs had significantly higher overall levels of dieting (p=0.006) but no significant age-by-group interactions. Among E/UEs, significant age-by-group interactions were observed vs HEs, with significantly increased levels of dieting from age 14 to 16 years (p_Bonferroni=0.026) and binge eating from ages 14 to 19 (p_Bonferroni=0.028) and 14 to 23 years (p_Bonferroni<0.001).

These findings demonstrate that unhealthy eaters (REs and E/UEs) were characterized by varying trajectories of ED symptoms during adolescence, with increasing rates of dieting and binge eating, particularly among E/UEs. According to the researchers, this suggests a greater risk for bulimia nervosa. [J Abnorm Psychol 2017;126:38-51]

On univariate analyses, internalizing problems (IPs) significantly increased with age among REs (β, 0.073; p=0.008) and E/UEs (β, 0.110; p<0.001) vs HEs. E/UEs also had higher levels of IPs at age 14 years than HEs (β, 0.712; p=0.001). These findings underline the link between emotional eating and psychological well-being. [Appetite 2018;125:410-417]

E/UEs had higher levels of externalizing problems (EPs) reported at age 14 years vs HEs (β, 0.855; p<0.001) and REs (β, 0.743; p=0.002).

Internalizing and externalizing psychopathological symptoms may serve as premorbid risk factors for EDs. [Int J Eat Disord 2014;47:860-869; Eur Child Adolesc Psychiatry 2008;17:82-91; Int J Eat Disord 2010; 43:149-160] EPs in early adolescence predict the onset and persistence of eating pathology, while generalized anxiety symptoms predict adolescent-onset ED. [JAMA Netw Open 2020:3:e2026874; J Abnorm Child Psychol 2013;41:1083-1096; J Child Psychol Psychiatry 2019;60:686-696]

Protracted brain maturation

Compared with HEs, REs and E/UEs had less pronounced age-related reductions in volumes and thickness in various brain regions, particularly in the cerebellum and prefrontal cortex (PFC), suggesting protracted brain maturation.

“Our finding of protracted cerebellar maturation in unhealthy eaters suggests disrupted development of such a satiety network and engagement in restrictive eating as a compensatory mechanism to consciously control weight gain,” the investigators explained.

“Additional alterations in reward (right putamen) and prefrontal (eg, right PFC) circuitry might lead E/UEs to also engage in disinhibited eating due to impairments in self-regulation and impulsive action control, making them more susceptible to emotional or uncontrolled eating behaviours,” they continued.

EDS are serious psychiatric issues

EDs are serious psychiatric disorders with high mortality rates, substantial effects on quality of life, and economic burdens. [EClinicalMedicine 2023;65:102294; Curr Opin Psychiatry 2020;33:521-527] Their increasing prevalence, particularly during mid-adolescence, underpins the need for early detection and effective interventions. [Eur Child Adolesc Psychiatry 2022;31:1827-1845; Curr Opin Psychiatry 2021;34:515-524; Mol Psychiatry 2022;27:281-295]

“[The] findings underscore the potential benefits of education targeting early maladaptive coping mechanisms and dietary habits to prevent EDs while promoting brain health,” the investigators concluded.