Related Experiment Video
Updated: Aug 8, 2026
Control of Eating Behavior Using a Novel Feedback System
Published on: May 8, 2018
The timing of solid introduction in an 'obesogenic' environment: a narrative review of the evidence and
Lynne Daniels1, Kimberley M Mallan1, Alison Fildes1,2
1School of Exercise and Nutrition Sciences and Institute of Health and Biomedical Innovation, Queensland University of Technology.
Insights
Introducing solids before 4 months may increase childhood obesity risk. However, evidence does not strongly support adverse outcomes for introducing solids between 4-6 months versus 6 months.
Area of Science:
- Pediatric Nutrition
- Public Health
- Obesity Research
Background:
- Infant feeding practices significantly influence long-term health outcomes.
- Current guidelines recommend exclusive breastfeeding for six months, but many infants in developed countries receive solids earlier.
- The association between the timing of solid food introduction and obesity risk requires further investigation.
Purpose of the Study:
- To review existing evidence on the relationship between the timing of solid food introduction and obesity risk in infants.
- To assess the quality of studies examining early versus later introduction of complementary foods.
Main Methods:
- Systematic review of studies published between 1990 and March 2013.
- Included papers focused on weight status or obesity prevalence outcomes in healthy term infants.
- Predominantly cohort studies were analyzed, with attention to methodological limitations.
Main Results:
- Twenty-six relevant papers were identified, with ten reporting a positive association between early solids and obesity risk.
- Only two large, high-quality studies found a positive association, both examining introduction before 4 months.
- No significant protective effect was found for introducing solids at 4-6 months compared to 6 months in four high-quality studies.
Conclusions:
- Introducing solids before 4 months of age may be linked to a higher risk of childhood obesity.
- There is limited evidence suggesting adverse weight outcomes from introducing solids between 4-6 months compared to 6 months.
- Further high-quality research is needed to establish optimal complementary feeding guidelines.
Objective:
To evaluate the evidence for association between obesity risk outcomes >12 months of age and timing of solid introduction in healthy term infants in developed countries, the large majority of whom are not exclusively breastfed to six months of age.
Methods:
Studies included were published 1990 to March 2013.
Results:
Twenty-six papers with weight status or obesity prevalence outcomes were identified. Studies were predominantly cohort design, most with important methodological limitations. Ten studies reported a positive association. Of these, only two were large, good-quality studies and both examined the outcome of early (<4 months) introduction of solids. None of the four good-quality studies that directly evaluated current guidelines provided evidence of any clinically relevant protective effect of solid introduction from 4-5 versus ≥6 months of age.
Conclusion:
The introduction of solids prior to 4 months of age may result in increased risk of childhood obesity but there is little evidence of adverse weight status outcomes associated with introducing solids at 4-6 rather than at six months.
Implications:
More and better quality evidence is required to inform guidelines on the 'when, what and how' of complementary feeding.
Related Concept Videos
01:06Fats as Energy Storage Molecules
01:11Observational Studies
There are three types of observational studies – Prospective, retrospective, and cross-sectional.
Prospective Study
Prospective studies, also known as longitudinal or cohort studies, are carried out by collecting future data from groups sharing similar characteristics. One example of...
01:07Teratogenicity
01:16Bioequivalence: Overview
01:03Dose-Response Relationship: Overview
01:28Development of the Oral Microbiota