Summary of findings for the main comparison. Animal‐source foods compared to a cereal‐based food or no intervention for supporting optimal growth and development in children aged 6 to 59 months.

Animal‐source foods compared to a cereal‐based food or no intervention for supporting optimal growth and development in children aged 6 to 59 months
Patient or population: children aged 5 to 59 months Setting: China, the Democratic Republic of Congo, Ecuador, Guatemala, Pakistan, the USA, Zambia Intervention: animal‐source food Comparison: a cereal‐based food or no intervention
Outcomes	Impacts	№ of participants (studies)	Quality of the evidence (GRADE)	Comments
Linear growth Assessed with: HAZ or LAZ scores Follow‐up: 5 to 12 months	3 studies found a significant increase in HAZ and LAZ scores in the intervention group compared to the no intervention (2 studies) or cereal‐based (1 study) control groups.	2972 (5 RCTs)	⊕⊝⊝⊝ Very lowa,b,c
	1 study found no significant difference between the intervention group and the control group receiving a fortified cereal; LAZ scores declined in both groups.
	1 study found a significant, smaller decrease in LAZ scores in the intervention group compared to the control group receiving a fortified or an unfortified cereal.
Weight gain Assessed with: WAZ scores Follow‐up: 5 to 12 months	3 studies found a small but significant increase in WAZ scores in the intervention group compared to the no intervention or cereal‐based control groups	2972 (5 RCTs)	⊕⊝⊝⊝ Very lowa,b,c
	1 study found no significant difference between the groups; WAZ scores decline in both groups.
	1 study found a significant, smaller decrease in WAZ scores in the intervention group compared to the control group receiving a fortified cereal; both groups declined.
All‐cause morbidity Assessed with: number of participants with at least 1 episode of any disease during the study Follow‐up: 6 to 12 months	1 study found significant reductions in incidence and duration of respiratory infections and diarrhea in the intervention group compared to the control group.	1612 (3 RCTs)	⊕⊝⊝⊝ Very lowa,d,e
	1 study found a significant increase of 5.5% in acute diarrhea in the intervention group compared to the control group, but no differences in fever, respiratory infections, or skin conditions between the groups.
	1 study found no significant differences between the groups for morbidities, including pneumonia, malaria, and diarrhea.
Anemia (not measured)	‐	‐	‐	Not measured
GRADE Working Group grades of evidence High quality: We are very confident that the true effect lies close to that of the estimate of the effect. Moderate quality: We are moderately confident in the effect estimate; the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low quality: Our confidence in the effect estimate is limited; the true effect may be substantially different from the estimate of the effect. Very low quality: We have very little confidence in the effect estimate; the true effect is likely to be substantially different from the estimate of effect.
HAZ: height‐for‐age z score; LAZ: length‐for‐age z score; RCT: randomized controlled trial; WAZ: weight‐for‐age z score.

^aDowngraded one level due to high risk of bias: baseline imbalances between groups or study funding.
 ^bDowngraded two levels for inconsistency: substantial heterogeneity (I² > 90%) and varying directions of intervention effects.
 ^cDowngraded one level for imprecision: wide magnitude of effects.
 ^dDowngraded one level for imprecision in measures used to assess morbidities.
 ^eDowngraded one level for inconsistency between reported differences.