Early life interventions
Early interventions to reduce obesity later in life
This work package addresses the scientific basis for early interventions to reduce obesity later in life through biomedical, genetics, historical, sociological and epidemiological approaches.
The overall aim is to identify specific early life interventions within the nutrition and physical activity area that reduce the risk of obesity later in life.
This specifically includes analyses of
- the relation between early nutrition and physical activity and risk of later obesity
- how this association is influenced by genetic risk profile
- how caring practices of parents of children at risk of obesity are influenced by interventions from public authorities and other actors
- the historical development of early life interventions in Denmark in relation to stages in the obesity epidemic
Increasingly, evidence suggests that early life factors during pregnancy and infancy are strongly associated with obesity later in life. However, the causal role of these associations, and the interactions with the genetic susceptibility, are poorly understood. Disentangling how early life factors influence the risk of later obesity is needed to identify early life interventions capable of reducing obesity.
Systematic reviews have confirmed a strong association between high postnatal weight gain and later obesity (Druet et al., 2012, Young et al., 2012, Andersen et al., 2012, Schack-Nielsen et al., 2010). However, no data yet supports that interventions to reduce early weight gain can reduce the risk of obesity later in life. Public health authorities worldwide give infant feeding recommendations but there is limited evidence with regard to prevention of obesity. Also, the effects of physical activity during the first years of life and possible interventions are unknown.
Considerable differences exist between infant feeding recommendations and parental practices (Tatone-Tokuda et al., 2009) which differ according to social and cultural background (Pak-Gorstein et al., 2009). Mothers’ concerns regarding infant feeding undergo extensive change during the first years of life. How interventions can help parental feeding practices accommodate the risk of obesity in later life must be investigated.
Time is a key element in the obesity epidemic. Child obesity was nearly nonexistent in Denmark until the early 1940s. The frequency reached a plateau in the early 1950s, until a steep increase set in again during the 1970s (Bua et al., 2007, Sørensen et al., 2012). During this period, recommendations on infant feeding and care changed dramatically (Løkke, 2012), but the possible relations between recommendations and obesity have not been studied yet.
Three existing cohorts form the basis for studies combining methods with biomedical, genetical and sociological approaches:
SKOT I is a cohort of 300 children which were followed from the age of 9 month to 3 years. The data includes recording of food intake and physical activity, assessment of body weight and -composition, as well as collection of samples (blood, urine and stool). SKOT II is a cohort of 200 children of obese mothers observed in the same way as SKOT I. A 36-month follow-up of the SKOT II cohort has been completed. A follow-up examination of the children in the SKOT I and II cohortsat age 9-10 years is planned and applications for funding will be submitted 2016. The SKOT I and II cohorts allow a detailed description of nutrition and growth as well as genetic, metabolic, endocrine, metabolomics and microbiota profiles during a period, which is important for the programming of obesity. Qualitative in-depth interviews are conducted with selected mothers from the SKOT II cohort, with the aim to describe parent experiences with young children at risk of obesity.
A SKOT III cohort is established as part of GO, comprising exclusively-breastfed infants with a very high early weight gain (> 2 SD weight-for-age at age 4-6 months). The aim is to identify the causes for this high weight gain, which is of interest to better understand regulation of appetite and satiety early in life. As stated above there is a strong association between high postnatal weight gain and later obesity but it is a common understanding that the risk is not increased in infants who are breastfed. As there is also evidence for a protecting effect of breastfeeding against later obesity a better understanding of causes and long term consequences of a very high weight gain in the SKOT III cohort is of interest in relation to the identification of effects early life interventions to reduce the risk of later obesity. The Danish National Birth Cohort (DNBC) comprises 100,000 enrolled pregnancies, from which detailed information is collected about pregnancy, infant growth and diet at various stages, including follow-up surveys at ages 6 months, 18 months, 7 and 11 years.
The DNBC will be used to analyze the effect of infant feeding on obesity at the ages of 7-11 y while taking into account the psychosocial context. Genetic analysis will be performed in selected groups of children of obese mothers, children of randomly selected control group mothers and overweight children.
To test the hypothesis that changes in dietary recommendations may have precipitated the obesity epidemic, we analyse the changes in recommendations from 1930 through to the present day. Furthermore, historical health visitor records will be used in an epidemiological analysis of the co-variation of the advice given and changes in prevalence of child obesity.
Visions for societal impact:
- To obtain a better understanding of the causal factors behind early obesity, providing novel dimensions in outlining approaches to effective interventions and balancing responsibilities for prevention of early development of obesity. Implementation is facilitated by close contact to health visitors and private practitioners in Denmark, who reach every family. The study of genetic risk scores might identify gene-nutrient and gene-physical activity interactions, making it possible to target interventions to individuals with a particularly high risk of obesity.
- Andersen LG, Holst C, Michaelsen KF, Baker JL, Sørensen TIA. Weight and weight gain during early infancy predict childhood obesity: a case-cohort study. Int J Obes (Lond). 2012 Aug doi: 10.1038/ijo.2012.134. [Epub ahead of print]
- Bua, J, LW Olsen og TIA Sørensen, "Secular Trends in Childhood Obesity in Denmark During 50 Years in Relation to Economic Growth&ast." Obesity 15: 4 (2007): 977-985.
- Druet C, Stettler N, Sharp S, Simmons RK, Cooper C, Smith GD, Ekelund U, Lévy-Marchal C, Jarvelin MR, Kuh D, Ong KK. Prediction of childhood obesity by infancy weight gain: an individual-level meta-analysis. Paediatr Perinat Epidemiol. 2012 Jan;26(1):19-26.
- Løkke, A 2012, ' Livgivende og farlig, moderpligt og kvindelig potens - kvindemælk og amning 1750-2010 '. H Bondevik & AK Lie (red), i: Rødt og Hvitt. Om blod og melk i fortid og samtid. Unipub forlag - Oslo Academic Press, Oslo, s. 163-186.
- Pak-Gorstein, S., Haq, A., & Graham, E.A. 2009. Cultural Influences on Infant Feeding Practices. Pediatrics in Review, 30, (3) E11-E218.
- Schack-Nielsen L, Michaelsen KF, Gamborg M, Mortensen EL, Sørensen TIA. Gestational weight gain in relation to offspring body mass index and obesity from infancy through adulthood. Int J Obes (Lond). 2010 Jan;34(1):67-74
- Sørensen TIA, Rokholm B, Ajslev TA. The History of the Obesity Epidemic in Denmark [Book chapter 9]. In Insecurity, inequality, and obesity in affluent societies. In: Proceedings of the British Academy 174., 161-178. The British Academy 2012.
- Tatone-Tokuda, F., Dubois, L., & Girard, M. 2009. Psychosocial Determinants of the Early Introduction of Complementary Foods. Health Education & Behavior, 36, (2) 302-320.
- Young BE, Johnson SL, Krebs NF. Biological determinants linking infant weightgain and child obesity: current knowledge and future directions. Adv Nutr. 2012 Sep 1;3(5):675-86.