Body mass index in parents and their adult offspring: A systematic review and meta-analysis

Abstract

Obesity may track across generations, due to genetics and shared family environmental factors, or possibly intrauterine programming. However, many studies only assess associations between maternal body mass index (BMI) and offspring BMI in childhood. To determine whether maternal and paternal associations with offspring BMI differ and whether associations persist into adulthood, a systematic review and meta-analysis was done. PubMed, Embase, Web of Science, and Google Scholar (to October 2022) were searched. Observational studies reporting associations between maternal or paternal BMI and adult offspring BMI were included. Offspring BMIs were reported as continuous or categorical measures. Forty-six studies were included in the systematic review. Meta-analyses were conducted using random-effects models. Parental BMI was positively associated with offspring BMI in adulthood. The pooled mother-offspring standardized mean difference (SMD) was 0.23 (95% confidence interval [CI]: 0.20, 0.26), and father-offspring SMD was similar: 0.22 (95% CI: 0.19, 0.25) in adjusted models. Offspring of mothers with overweight or obesity had the same risk of higher BMI as offspring of fathers with overweight or obesity. If these associations are causal, they support interventions targeting all family members, rather than focusing solely on mothers, to obtain a healthy weight development among offspring.

Keywords: adult offspring; body mass index; intergenerational; systematic review.

FIGURE 1

Meta‐analysis of the association between parent and offspring BMI (SMD). The effect size estimate is the SMD with 95% CI (per SD of parental BMI). The size of the squares' estimates is proportional to the weight assigned to each study. Diamonds represent pooled estimates from a random effects meta‐analysis. The I ² and P values for heterogeneity are shown. BMI, body mass index; CI, confidence interval; SD, standard deviation; SMD, standardized mean difference.

FIGURE 2

Meta‐analysis of the association between parent and offspring BMI at sex‐specific level (SMD). The effect size estimate is the SMD with 95% CI (per SD of parental BMI). The size of the squares' estimates is proportional to the weight assigned to each study. Diamonds represent pooled estimates from a random effects meta‐analysis. The I ² and P values for heterogeneity are shown. BMI, body mass index; CI, confidence interval; SD, standard deviation; SMD, standardized mean difference.

FIGURE 3

Difference in SMD between mother–offspring and father–offspring BMI associations. Left plot: SMD (95% CI) in each subgroup of each study. Right plot: Difference of SMD comparing effects for mother–offspring and father–offspring in each study with a fixed‐effects meta‐analysis of these differences of SMD. The size of the squares and circles is proportional to the weight assigned to each study. Open circles represent pooled estimates. CI, confidence interval; SMD, standardized mean difference.