title: Introduction of complementary feeding before 4months of age increases the risk of childhood overweight or obesity: a meta-analysis of prospective cohort studies.
abstract: The association between the age at introduction of complementary feeding and the risk of overweight or obesity during childhood has been hotly debated, but the result remains uncertain. This meta-analysis of prospective cohort studies attempted to evaluate this association, as well as provide evidence for infant feeding recommendations. The PubMed, Embase, and Cochrane databases were systematically searched for relevant original articles published prior to March 1, 2015 that met predefined inclusion criteria. The pooled relative risks (RRs) and corresponding 95% confidence intervals (CIs) were calculated using fix-effect or random-effect models, which were chosen based on heterogeneity among studies. Ten articles consisting of 13 studies, where 8 measured being overweight as an outcome and 5 measured being obese, were included in this meta-analysis. There were a total of 63,605 participants and 11,900 incident cases in the overweight studies, and 56,136 individuals and 3246 incident cases in the obese studies. The pooled results revealed that introducing complementary foods before 4months of age compared to at 4 to 6months was associated with an increased risk of being overweight (RR, 1.18; 95% CI, 1.06-1.31) or obese (RR, 1.33; 95% CI, 1.07-1.64) during childhood. No significant relationship was observed between delaying introduction of complementary foods after 6months of age, and being overweight (RR, 1.01; 95% CI, 0.90-1.13) or obese (RR, 1.02; 95% CI, 0.91-1.14) during childhood. The results of this study suggest that the introduction of complementary foods to infants before 4months of age should be avoided to protect against childhood obesity.
authors.affiliation: Jiangan Maternal and Child Health Hospital, Wuhan 430014, Hubei, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, MOE Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China.
authors.forename: Yuanjue
authors.initials: Y
authors.lastname: Wu
authors.affiliation: The Central Hospital of Wuhan, Wuhan 430014, Hubei, China.
authors.forename: Guoping
authors.initials: G
authors.lastname: Xiong
authors.affiliation: Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, MOE Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Chao
authors.affiliation: Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, MOE Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China.
authors.forename: Qiu
authors.initials: Q
authors.lastname: Jin
authors.affiliation: Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, MOE Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Liu
authors.affiliation: Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, MOE Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Hao
authors.affiliation: Department of Epidemiology and Biostatistics, MOE Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Wei
authors.affiliation: Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, MOE Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China.
authors.forename: Nianhong
authors.initials: N
authors.lastname: Yang
authors.affiliation: Department of Nutrition and Food Hygiene, Hubei Key Laboratory of Food Nutrition and Safety, MOE Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China. Electronic address: xxyxf@mails.tjmu.edu.cn.
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Yang
mesh_terms: D000367:Age Factors; D015992:Body Mass Index; D015331:Cohort Studies; D006801:Humans; D007223:Infant; D007227:Infant Nutritional Physiological Phenomena / Q000502:physiology*; D050177:Overweight / Q000453:epidemiology*; D063766:Pediatric Obesity / Q000453:epidemiology*; D011446:Prospective Studies; D012307:Risk Factors
keywords: Child feeding; Cohort study; Complementary feeding; Meta-analysis; Obesity; Overweight