Introduction
Childhood overweight/obesity (Ov/Ob) is a major public health problem, of greater concern when accompanied with comorbidities such as hypertension, insulin resistance leading to metabolically unhealthy obesity (MUO). Current evidence suggests a linkage between meal frequency, diet quality and nutritional status [1-3] in children and adolescents, however data regarding associationsbetween meal patterns, Ov/Ob risk and MUO are limited.
Aim
To explore associations between meal patterns and the risk of childhood Ov/Ob and MUO.
Methods
The PRISMA methodology was used to retrieve prospective studies and randomized controlled trials conducted in children/adolescents 2-19 years old in Europe, USA, Canada or Oceania, from 01/2013 to 06/2023. Exposures that were considered under the umbrella “meal patterns” included consumption of a meal, meal skipping, timing, format and context. The quality of the studies was assessed with the ROBINS-E and RoB-2 tools.
Results
Of the 3,020 studies initially retrieved, 27 were included. All studies reported on Ov/Ob risk, whilst no studies on MUO were identified. All but one study had a longitudinal study design. Twenty-two studies (81%) had a high/very high risk of bias, mainly due to the methods measures of exposure were assessed. Consumption of/skipping breakfast was the most common exposure, followed by consumption of lunch (n=5), dinner (n=5), meal frequency/eating occasion (EO; n=5) and consumption of fast foods (n=4). Some studies reported on meal context (eating while watching TV; n=4). In most studies, frequent breakfast and evening family dinners (i.e. 7 days/week vs <7days/week) were associated with lower odds of childhood Ov/Ob, BMI and %body fat at follow-up (FU). Four studies also showed that skipping breakfast was associated with increased obesity markers, while three studies showed no associations. There was limited evidence of a positive association between eating while watching TV and weight trajectories (n=2). No associations were reported in relation to frequency of lunch and fast food intake. Results regarding meal frequency/EO and Ov/Ob at FU are conflicting, with differences attributed to the definition of an EO.
Conclusion
Evidence supports that frequent consumption of breakfast and family dinners may be associated with lower Ov/Ob risk in children and adolescents, while eating in front of TV with increasing weight trajectories. No studies were identified in relation to MUO, highlighting a significant research gap. Nevertheless, clear definition on EOs and improved methodological approach in the assessment of meal patterns emerged as a need, according to current review findings.
Acknowledgements
The Bio-Streams project has received funding from the European Union’s HORIZON 2022 research and innovation programme under grant agreement No 101080718.

**Introduction**
Childhood overweight/obesity (Ov/Ob) is a major public health problem, of greater concern when accompanied with comorbidities such as hypertension, insulin resistance leading to metabolically unhealthy obesity (MUO). Current evidence suggests a linkage between meal frequency, diet quality and nutritional status [1-3] in children and adolescents, however data regarding associationsbetween meal patterns, Ov/Ob risk and MUO are limited.
**Aim**
To explore associations between meal patterns and the risk of childhood Ov/Ob and MUO.
**Methods**
The PRISMA methodology was used to retrieve prospective studies and randomized controlled trials conducted in children/adolescents 2-19 years old in Europe, USA, Canada or Oceania, from 01/2013 to 06/2023. Exposures that were considered under the umbrella “meal patterns” included consumption of a meal, meal skipping, timing, format and context. The quality of the studies was assessed with the ROBINS-E and RoB-2 tools.
**Results**
Of the 3,020 studies initially retrieved, 27 were included. All studies reported on Ov/Ob risk, whilst no studies on MUO were identified. All but one study had a longitudinal study design. Twenty-two studies (81%) had a high/very high risk of bias, mainly due to the methods measures of exposure were assessed. Consumption of/skipping breakfast was the most common exposure, followed by consumption of lunch (n=5), dinner (n=5), meal frequency/eating occasion (EO; n=5) and consumption of fast foods (n=4). Some studies reported on meal context (eating while watching TV; n=4). In most studies, frequent breakfast and evening family dinners (i.e. 7 days/week vs <7days/week) were associated with lower odds of childhood Ov/Ob, BMI and %body fat at follow-up (FU). Four studies also showed that skipping breakfast was associated with increased obesity markers, while three studies showed no associations. There was limited evidence of a positive association between eating while watching TV and weight trajectories (n=2). No associations were reported in relation to frequency of lunch and fast food intake. Results regarding meal frequency/EO and Ov/Ob at FU are conflicting, with differences attributed to the definition of an EO.
**Conclusion**
Evidence supports that frequent consumption of breakfast and family dinners may be associated with lower Ov/Ob risk in children and adolescents, while eating in front of TV with increasing weight trajectories. No studies were identified in relation to MUO, highlighting a significant research gap. Nevertheless, clear definition on EOs and improved methodological approach in the assessment of meal patterns emerged as a need, according to current review findings.
**Acknowledgements**
The Bio-Streams project has received funding from the European Union’s HORIZON 2022 research and innovation programme under grant agreement No 101080718.

OC56 - Meal patterns and risk of childhood obesity and metabolically unhealthy obesity: a systematic review of the evidence, methodological issues and research gaps.

Unique to the new Congress (previously the Summer Conference) is that you will have greater opportunity to engage with more nutrition science than ever before. In 2024 the core programme will be delivered by the Irish Section of The Nutrition Society, supported by the Science Committee. The theme of these symposia will be ‘new data – focused approaches and challenges’. Outside of the core programme you will have the chance to hear the latest research from the Society’s partner organisations, universities, the private sector and more, on a diverse range of research.