Intended for healthcare professionals


Being big or growing fast: systematic review of size and growth in infancy and later obesity

BMJ 2005; 331 doi: (Published 20 October 2005) Cite this as: BMJ 2005;331:929
  1. Janis Baird, research fellow (jb{at},
  2. David Fisher, research assistant1,
  3. Patricia Lucas, lecturer2,
  4. Jos Kleijnen, director3,
  5. Helen Roberts, professor of child health4,
  6. Catherine Law, reader in children's health5
  1. 1MRC Epidemiology Resource Centre, University of Southampton, Southampton General Hospital, Southampton SO16 6YD
  2. 2School for Policy Studies, University of Bristol, Bristol BS8 1TZ
  3. 3Centre for Reviews and Dissemination, University of York, York YO10 5DD
  4. 4Child Health Research and Policy Unit, City University, London EC1Y 4TY
  5. 5Centre for Paediatric Epidemiology and Biostatistics, Institute of Child Health, University College London, London WC1N 1EH
  1. Correspondence to: J Baird
  • Accepted 16 August 2005


Objectives To assess the association between infant size or growth and subsequent obesity and to determine if any association has been stable over time.

Design Systematic review.

Data sources Medline, Embase, bibliographies of included studies, contact with first authors of included studies and other experts.

Inclusion criteria Studies that assessed the relation between infant size or growth during the first two years of life and subsequent obesity.

Main outcome measure Obesity at any age after infancy.

Results 24 studies met the inclusion criteria (22 cohort and two case-control studies). Of these, 18 assessed the relation between infant size and subsequent obesity, most showing that infants who were defined as “obese” or who were at the highest end of the distribution for weight or body mass index were at increased risk of obesity. Compared with non-obese infants, in those who had been obese odds ratios or relative risks for subsequent obesity ranged from 1.35 to 9.38. Ten studies assessed the relation of infant growth with subsequent obesity and most showed that infants who grew more rapidly were at increased risk of obesity. Compared with other infants, in infants with rapid growth odds ratios and relative risks of later obesity ranged from 1.17 to 5.70. Associations were consistent for obesity at different ages and for people born over a period from 1927 to 1994.

Conclusions Infants who are at the highest end of the distribution for weight or body mass index or who grow rapidly during infancy are at increased risk of subsequent obesity.


  • Contributors CL, JB, HR, and JK obtained funding. All authors were responsible for the concept and design of the study. JB, DF, and PL carried out the review work with assistance from CL, HR, and JK. All authors were responsible for the interpretation of findings. JB and CL produced the first draft of the paper, and all authors were responsible for critical revision of the manuscript. CL is guarantor.

  • Funding Department of Health. JB is an MRC Special training fellow in health services and health of the public research.

  • Competing interests None declared.

  • Ethical approval Not required.

  • Accepted 16 August 2005
View Full Text