Childhood maltreatment linked to higher body fat in systematic review of 12 studies

A systematic review published in the International Journal of Obesity has brought together the available evidence on how childhood maltreatment relates to body composition, and its conclusion is striking: nine of the twelve studies included reported a positive association between maltreatment before the age of 18 and higher adiposity, particularly among adults living in high-income countries.

The research team searched six databases — MEDLINE, Embase, LILACS, Scopus, PsycINFO and Web of Science — without language or date restrictions, up to 23 April 2026. From 2,993 records identified, twelve studies met the inclusion criteria, published between 2015 and 2026, with sample sizes ranging from 75 to 151,143 participants aged between 3 and 90 years. Three studies had a longitudinal design, five were cross-sectional, and four reported cross-sectional analyses within longitudinal designs. Nine of the twelve were conducted in high-income countries, with two in middle-income countries, Brazil and China, and one involving a collaboration between middle- and high-income countries.

What sets this review apart is its insistence on measuring fat directly rather than relying on BMI. Body mass index, the authors note, cannot distinguish fat mass from fat-free mass or characterise where fat is distributed in the body. The included studies therefore used compartmental methods such as dual-energy X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA), air displacement plethysmography, skinfold thickness, and in some cases combinations of BIA with magnetic resonance imaging or abdominal ultrasound. Across the twelve studies, these techniques generated 47 distinct body composition outcomes, with total body fat, visceral fat and android fat the most frequently reported measures.

The findings point consistently towards increased adiposity among people reporting maltreatment in childhood. In a study of 75 adults aged 19 to 55 years, individuals with a history of childhood maltreatment had higher visceral fat mass than those without such exposure — 1,136 grams versus 836 grams — although the authors caution that these analyses were not adjusted for potential confounders. Among university students in China, childhood maltreatment was positively associated with visceral fat, body fat percentage and fat mass, with physical abuse, sexual abuse and emotional neglect each linked to higher fat mass. In sex-stratified analyses, no associations were observed among females, whereas emotional abuse, physical abuse and neglect were associated with multiple adiposity measures among males.

Large population-based samples reinforced the pattern. In a study of 151,143 adults and older adults, childhood trauma scores were positively associated with relative fat mass, subcutaneous adipose tissue and visceral adipose tissue among women, with positive associations among men only for relative fat mass and visceral adipose tissue. A more consistent dose-response pattern emerged among women, with an increasing number of maltreatment events associated with higher adiposity levels. Another study of adults and older adults aged 46 to 90 years found that individuals reporting three or four types of childhood maltreatment had 1.19-fold and 1.26-fold higher odds of obesity, defined by body fat percentage thresholds, than those reporting no maltreatment. A further large study of middle-aged and older adults found that childhood maltreatment was associated with greater central adiposity and a less favourable muscle-to-fat ratio after adjustment for confounders.

Not every study found a link, and the pattern of null results is itself informative. Three studies — all conducted in children or adolescents, and all with an exposure-outcome interval of less than five years — reported associations only in unadjusted analyses, which disappeared after adjustment for confounding variables. The only study reporting a significant association in this age group examined fat mass index trajectories between 7 and 17 years of age in relation to severe discipline and physical punishment, and found that girls exposed to physical punishment showed a steeper increase in fat mass index over time than non-exposed girls. The review authors suggest, cautiously, that the effects of childhood maltreatment on body composition may require a longer latency period to become detectable, consistent with an incubation-period hypothesis proposed in earlier meta-analyses.

The review’s findings align with previous meta-analyses on childhood maltreatment and obesity. One analysis of 41 studies and 190,285 participants reported a higher lifetime risk of obesity among individuals exposed to childhood maltreatment, with an odds ratio of 1.36, while another covering 23 cohort studies and 112,708 participants found an odds ratio of 1.34. The new review extends this evidence by showing that the association holds not only for obesity defined anthropometrically but also for more specific indicators of adiposity, including total body fat, visceral fat, android fat and fat mass index. Notably, in one included study, higher visceral fat was identified despite no differences in BMI, illustrating how body composition assessment can reveal adiposity patterns that conventional measures miss.

Sex differences emerged as a recurring theme. Among the eight studies that performed sex-stratified analyses, five reported sex-specific associations. In women, several types of maltreatment were associated with higher fat mass, android fat index, subcutaneous adipose tissue and visceral fat, whereas among men, positive associations were observed for fat mass, body fat and visceral fat. Physical abuse and exposure to multiple forms of maltreatment showed the most consistent associations with adiposity outcomes, and one study found significant interactions between physical abuse and self-identification as White for both total body fat and visceral fat. The authors note that the available evidence remains inconsistent, however, and that the influence of the type and severity of maltreatment on later adiposity has not yet been fully established.

Several biological mechanisms have been proposed to explain the association. Childhood maltreatment and increased adiposity are both associated with chronic low-grade systemic inflammation, which may contribute to excess body fat accumulation, particularly in the visceral compartment. Other proposed pathways include dysregulation of the hypothalamic-pituitary-adrenal axis, immune system activation, altered cortisol regulation, changes in sex hormone-binding globulin and leptin, as well as mental health problems and maladaptive coping behaviours. The review also points to the well-documented links between visceral fat and cardiometabolic disease, neurodegeneration and increased mortality risk as reasons why these findings matter for public health.

The authors are careful about the limitations of their synthesis. Most included studies relied on retrospective self-reported assessment of childhood maltreatment, often collected in adulthood many years after the exposure, which may compromise accuracy. Substantial methodological heterogeneity in exposure assessment, body composition measures, study populations and analytical approaches precluded the quantitative meta-analysis planned in the registered protocol, so a narrative synthesis was performed instead. Effect sizes were generally small to moderate, suggesting incremental rather than large differences in body composition. The authors call for further longitudinal research on children, adolescents and populations from low- and middle-income countries, with standardised definitions of maltreatment and harmonised body composition assessments, to clarify the specific effects of different types of maltreatment and to inform targeted prevention strategies.

Subject of Research: The association between childhood maltreatment and body composition indicators

Article Title: Association between childhood maltreatment and body composition: a systematic review

Article References: Estrela, R. V. D. F., Xavier, M. O., Mosquera, P. S., Bonilla, C., Pastor-Valero, M., & Matijasevich, A. (2026). Association between childhood maltreatment and body composition: a systematic review. International Journal of Obesity. https://doi.org/10.1038/s41366-026-02235-8

Image Credits: AI Generated

DOI: 10.1038/s41366-026-02235-8

Keywords: childhood maltreatment, body composition, adiposity, visceral fat, systematic review, obesity, BMI, DXA, fat mass, HPA axis, high-income countries, International Journal of Obesity