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

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 associations between meal patterns, Ov/Ob risk and MUO are limited. The aim was to explore associations between meal patterns and the risk of childhood Ov/Ob and MUO. 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. 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