This newly published Cochrane Review assessed the effectiveness of animal-source foods compared to any other feeding interventions or no intervention in improving growth and developmental outcomes in children aged 6 to 59 months.
The review included 6 studies involving 3036 children aged 5 to 50 months. Studies were conducted in China, Democratic Republic of Congo, Ecuador, Guatemala, Pakistan, USA and Zambia, and lasted between 5 and 12 months.
Three studies compared the effects of feeding an animal-source food with a fortified (iron or iron and zinc) or unfortified cereal; two used a control group with no interventon; and one compared a meat-based diet to a diary-based diet. The types of animal-source foods tested included yoghurt, eggs, cheese, lyophilized (freeze-dried) beef product, ground and frozen pork, and puréed jarred beef with gravy or pork, and powered whey protein.
Three studies (592 children) reported increases in weight-for-age as well as height-for-age or length-for-age in infants consuming animal-source foods compared to infants consuming cereal-based foods or no interevntion. One study (1062 children) found that both groups decreased in weight-for-age and length-for-age, with no differences between the groups. In another study (1318 children), both groups also decreased for these outcomes, but the decrease was smaller in the intervention group compared to the control group.
One study with yogurt (402 children) found that children who received yogurt were less likely to experience diarrhea and respiratory infection and recovered faster when they did. One study with eggs (148 children) showed an increase in the incidence of diarrhea in children fed eggs, but this may have been due to cultural associations between eggs and gastrointestional problems. There were no differences in fever, respiratory infections, or skin conditions between the groups. The third study (1062 children) found no differences between the groups for any measures of disease.
One study (64 children) found that infants consuming a meat-based diet showed a significant increase in length-for-age compared to infants consuming a dairy-based diet who experienced a decrease in length for age. Both groups experienced an increase in weight-for-age but there was no difference between them.
The review authors rated the overall quality of the evidence as very low.
The reviewers concluded that they are uncertain of the effects of animal-source food versus cereal products or no intervention on the growth or development of children, and that further research is likely to change the estimate of magnitude and direction of treatment effect.
Read the full review here.