Family meals are positively associated with healthier diets among children and parents. We aimed to deepen the understanding of these relationships by exploring the associations between shared meals and dietary quality among children, fathers and mothers. A subset of parent-child dyads (296 children aged 3–6 years, 103 fathers, 293 mothers) from the DAGIS Intervention baseline assessment was included in this cross-sectional study. The parents reported how often they shared meals with the child and filled in a food frequency questionnaire assessing their child’s and their own food consumption. A Healthy Food Intake Index (HFII) describing dietary quality was calculated for all family members. We used linear regression to investigate the associations between shared meals and the HFII of the children, fathers and mothers. Models were adjusted for child’s age and gender, parent’s age and educational level and number of children in the household. Children whose fathers reported less frequently sharing a weekend lunch with the child had a lower HFII (B estimate –1·58, 95 % CI –2·66, –0·50). The association remained close to statistical significance with adjustments (B estimate –0·99, 95 % CI –2·17, 0·19). A less frequently shared weekend lunch was also borderline significantly associated with lower HFII among the fathers (adjusted model, B estimate –1·13, 95 % CI –2·30, 0·04). Fathers should be encouraged to share meals with their family, since it might have a role in the dietary quality of both children and fathers. Future studies should recognise fathers as important contributors to a healthy home food environment.

In Aotearoa New Zealand, approximately 1 in 3 adults and 1 in 8 children are classified as obese, with Māori and Pacific communities disproportionately affected(1). While maternal nutrition has been extensively studied, paternal impacts and the combined effect of both parents’ obesogenic environments on offspring health remain underexplored(2). The primary objective of this study is to characterise the metabolic phenotype of parent rats fed a High Fat High Sugar (HFHS) diet and investigate the birth characteristics of their offspring, from a factorial mating design.Eighty female and 40 male Sprague-Dawley rats were randomised to a standard chow diet (SD) (24% protein, 18% fat, 58% carbohydrates) or HFHS diet (Specialty Feeds SF23-120: 16% protein, 41% fat, 43% carbohydrates) for five weeks prior to mating. Females were then continued on their respective diets throughout pregnancy and lactation. Four mating combinations were established: SDmum-SDdad, SDmum-HFHSdad, HFHSmum-SDdad, and HFHSmum-HFHSdad. A subset of parents (n=38) underwent body composition assessments using dual-energy X-ray absorptiometry (DEXA). Additionally, a subgroup (n=23) was evaluated for metabolic profiles using Prometheon metabolic cages. Offspring birth weights and body lengths were recorded. The HFHS diet’s efficacy was confirmed in both male and female rats, with HFHS groups showing higher body weight (females: 327.1 g ± 19.7 vs. 288.2 g ± 20.1; males: 575.8 g ± 39.8 vs. 532.6 g ± 50.3; p < 0.05), greater fat percentage (females: 46.8% ± 5.6 vs. 29.2% ± 5.6; males: 40.5% ± 7.2 vs. 28.7% ± 6.8; p < 0.001), and a lower respiratory exchange ratio (RER) (females: 0.8108 ± 0.0275 vs. 0.8679 ± 0.0288; males: 0.8257 ± 0.0304 vs. 0.8759 ± 0.0266; p < 0.05) compared to the SD group. In male offspring, birth weights in HFHSmum-SDdad (6.3 g ± 0.9) and HFHSmum-HFHSdad (6.0 g ± 0.9) groups were significantly lower (p < 0.0001) than in SDmum-SDdad (6.980 g ± 0.7753) and SDmum-HFHSdad (7.0 g ± 0.7) groups. Birth weights were further reduced in HFHSmum-HFHSdad versus HFHSmum-SDdad (Mean Diff. = 0.3g; p < 0.05).Body lengths in HFHSmum-HFHSdad males were shorter (43.1 mm ± 3.2; p < 0.0001) compared to other groups (≥ 45.3 mm). Female offspring birth weights were lower in the HFHSmum-SDdad (5.8g ± 0.8) and HFHSmum-HFHSdad groups (5.8 g ± 0.9; p<0.0001) compared to the other groups (means ≥ 6.4g) but paternal HFHS diet had no additional effect on birth weight. As with males, body lengths in the HFHSmum-HFHSdad female offspring were significantly shorter (4 mm ± 3; p<0.0001) compared to all other groups (≥44mm). Parental HFHS diets synergistically reduce offspring birth length and weight, with stronger effects in males. These findings underscore the importance of inclusive dietary guidelines for both parents to reduce intergenerational obesity risk and support long-term health.