Hoppe, Molgaard, Thomsen, Juul., and Michaelsen, (2004) explored the potential link between protein intake as an infant and body size as well as body weight. This Danish study of 142 health term infants conclude that while protein intake (PI) in infancy was a predictor of future childhood weight and height, PI was not a predictor of obesity. While the authors noted a positive correlation between PI and height and body size at 9 months and 10 years of age, there was no correlation between PI and body fat at 10 years of age. PI in infancy seem to stimulate early growth but these growth affects are not maintained throughout adolescence.

Armstrong and Reilly (2002) investigated the relationship between breast feeding and obesity in Scottish children. This large study of 32,200 children demonstrated that the prevalence of obesity was lower in breastfed children as compared to formula fed children. The data for this study (gathered from children 39-42 months of age) were adjusted to control for other variables such as socioeconomic status, gender, and birth weight. The authors also noted that childhood obesity was also significantly and positively correlated with birth weight.

Dorosty, Emmett, Cowin, and Reilly (2000) conducted a study of the association between adiposity rebound (AR) and dietary intake, parental BMI, socioeconomic status and childhood BMI. This longitudinal British study of 889 children followed from birth to 5 years concluded that while others reported evidence that AR, the time at which the body mass index increases after it’s lowest point in childhood is a critical period for the development of obesity, the authors could not substantiate the evidence. In addition the study’s authors concluded that there was no association between high protein intake (or any other dietary variable) and the timing of AR. The authors suggest that parental obesity was a better predictor of very early (at or before 43 months) or early (from 49 to 61 months) AR and childhood obesity as measured by BMI..

While adult obesity may be outside the limits of this review, researchers have looked to childhood obesity as a predictor of obesity in adulthood. Pengelly, Viner, and Cole (2005) conducted a study in Great Britain that evaluated the long term psycho-social health of adults who were obese as children. They concluded that although the psycho-social stigma of obesity affected the child during the years they were overweight, if the obesity did not extend into adulthood, there were no long term adverse psycho-social effects. However the study did conclude that child to adult obesity in women was linked to poor employment outlook and relationship outcomes. The researchers concluded from their data that efforts should be focused on preventing the persistence of obesity from childhood to adulthood.

Moffat, Galloway, and Latham (2005) tested the hypothesis that children’s body size and shape vary depending on their neighborhood. This Canadian study concluded that there was no difference between neighborhoods, but there were differences in body shape and size among children of varying socioeconomic backgrounds. Those authors found that children in the two lowest socioeconomic classifications were more likely to be obese.

Burdette and Whitaker (2005) studied the relationship between neighborhood safety, outdoor play, television viewing, and obesity in children. Their study of children living in 20 large U.S. cities concluded that the mother’s perception of neighborhood safety was related to their children’s TV viewing time but not related to outdoor play time or risk for obesity.

While researchers search for physiological and socioeconomic origins for childhood obesity, a substantial volume of research supports the theory that childhood obesity is behavioral in origin. Researchers have focused on both parental behaviors and the behaviors of children.

Montgomery, and Ekbom (2002) conducted a retrospective study of approximately 17,000 British children born between March 3 and March 9, 1959. Using a retrospective chart review 11,359 children born during those years were evaluated in adulthood in their 33^rd year. The authors concluded that in utero exposure to smoking during pregnancy did increase the likelihood for obesity in adulthood. The authors suggested that this could be the result of a phenomenon they called programming that resulted in “lifelong metabolic dysregulation, possibly due to fetal malnutrition or toxicity (p. 27).”

Parental restriction of children’s eating was one variable included in an American study of pediatric obesity (Faith, Dennison, Edwards, and Stratton, 2006). The study of 2801 New York children concluded that parents who had children at risk for obesity were more likely to restrict feeding. Interestingly, the study noted that parental behavior was not influenced by their exposure to nutritional messages. The study further concluded that parental offering of whole fruits was associated with reduced adiposity gain.

Settler, Kumanyika, Katz, Zemel, and Stallings (2003) investigated the relationship between rapid weight gain in infancy and obesity in young adulthood. They concluded that in their study of African Americans young adults, rapid weight gain as infants was a predictor of obesity in young adulthood. They proposed that nutrition during early infancy was key to preventing obesity.

Many studies of child behaviors resulting in obesity focus on physical activity. For example, Drennan (2007) developed a nursery based physical activity intervention for Scottish infants. The author concluded that this early intervention with physical activity had no association with childhood obesity. The study concluded that there was no impact on BMI, nor on “habitual physical activity (p.6.).”

Some but not all researchers note a link between breakfast skipping and childhood obesity. Dialekatakou and Vranas (2008) investigated the causes for conflicting studies of breakfast skipping and its impact on BMI and/or obesity. The authors noted that many studies have found an association between breakfast skipping and BMI/obesity while several have found no relationship. Their study of 811 Greek students demonstrated that the discrepancies were attributable to methodological differences in the studies, particularly differences in researchers definitions of breakfast skipping.

Craeynest, Crombez, Deforche, Tanghe, and De Bourdeauhuij (2005) studied the link between childhood obesity and attitudes towards food and physical activity. Their study concluded that there was no difference in children’s attitudes toward healthy food and intense physical activity based upon the presence of obesity. Their study did find that children suffering from obesity had a more pronounced positive attitude towards food in general; the perception of healthy food and unhealthy food was not relevant for these children.

Dixon (2006) reported that obese children eat less when they are provided larger, but less frequent meals. In a study of 18 normal weight and 8 obese children, obese children consumed more when given frequent smaller meals than when given less frequent larger meals.

A number of interventions targeting childhood obesity are child focused. These child focused interventions target nutrition, physical activity or some combination of the two.

Children in Leeds, England were the focus of a intervention designed by Sahota, Rudolf, Dixey, Hill, Barth, and Cade (2001). The researchers program was a school based (but multiagency) health promotion program. While the authors stated that their intervention was child focused, the program actually targeted the school ethos (defined as school, family, and community). The study demonstrated the effectiveness of the program’s education but did not evaluate its impact on childhood obesity in the study’s population.

In the United States the feasibility of sharing high school athletic facilities with after-school physical activity programs is under investigation. The parameters and feasibility of such programs is debatable (In light of the Obesity Epidemic, 2007).

While debated in the U.S. the Australian government launched a child focused intervention targeting obesity in 2004. This program encouraged community based partnerships whose goal was to increase after-school physical activity of 150,000 children. The program’s effectiveness (as measured by its impact on obesity) has not been reported (Allison, 2004).

A second Australian child focused intervention targeted the nation’s preschoolers. The study concluded that “an inclusion of physical activity principles in their Quality Improvement Accreditation System and Family Day Care Quality Assurance systems would assist in the development of programs specific to LDC [long day care] and FDC [family day care]” Lawlis, Mikhailovich, and Morrison, 2008, p. 32).

In New York, a 4-H Club based child focused intervention focused on walking as a means to increase physical activity and impact childhood obesity. This 4-H focus is refreshing as one of the Hs in the acronym stands for Health. An interesting paradox in this intervention was that while nutrition information was available for these children, it was delivered via a computer based information program (Winter, 2008). Other studies (Burdette and Whitaker, 2005) have pointed to video games and television viewing as potential factors contributing to childhood obesity.

In some instances interventions were developed that partnered schools and families. For example, Bloom-Hoffman, Wilcox, Dunn, Leff, and Power (2008) described the development and implementation of a literacy-based family component of a school based health program. This intervention used interactive children’s books so that parents, teachers and students received consistent nutrition information. Using the number of additional servings of fruits and vegetables per day (compared to a control group), the preliminary results of this intervention did not demonstrate significance.

Golley, Magarey, Baur, Steinbeck and Daniels (2007) studied the relative effectiveness of patenting skills training and its impact on obese Australian children. The authors’ intervention did not target nutrition education, but rather focused on improving the parenting skills needed to result in behavior modifications in children. After 12 months, the participant’s children’s BMI scores were reduced by approximately 10% compared with a 5% reduction in the control group. The authors concluded that parenting skills combined with promoting a healthy lifestyle may be an effective approach to reducing childhood obesity.

Similarly Golley, Perry, Magarey, and Daniels (2007) reported a case study focused on how general parenting principles could be used as a part of a family focused weight management program. The child whose parents participated in this case study saw a decrease in BMI from 23.4 to 22.3 and there was no increase in waist circumference during this 12 month study.

Childhood obesity presents an interesting dilemma for public health practitioners. Successful public health programs correctly narrow the unit of analysis (individual, family, neighborhood, etc.) and develop appropriate units of solution targeting the unit of analysis. Many interventions targeting childhood obesity focus on either behavior changes in the child, the family or a combination of both. It may be difficult to make improvements in childhood obesity rates with focus on a single unit of analysis, however a parent focused intervention with an emphasis on parent skills rather than parent education (nutrition and exercise content) seems promising.

Golley, Magarey, Baur, Steinbeck and Daniels (2007) intervention drew upon many tenants of the widely used health belief model (HBM) of individual health behavior. Central to the HBM model is the concept that “behavior is a function of the subjective value of an outcome and of the subjective probability, or expectation, that a particular action will achieve that outcome (Glanz, Lewis, and Rimer 1997, p. 42).” Further,

The HBM is a value expectancy theory. When value expectancy concepts were gradually reformulated in the context of health-related behavior, the translations were (1) the desire to avoid illness or to get well (value) and (2) the belief that a specific health action available to a person [or in this example a person’s child] would prevent (or ameliorate) illness (expectancy) (Glanz, Lewis, and Rimer, 1997, p. 43).

The intervention developed by Golley, Magarey, Baur, Steinbeck, and Daniels is somewhat innovative in that it relies on the application of the HBM to impact the behavior of the parent resulting in changes in behavior of their children. While the outcome measures of many obesity intervention programs target the effectiveness of education efforts, this study’s outcome measures (BMI and waist circumference) parallel those of the global health issue of childhood obesity.

While this intervention appears promising, it was a small study (111 overweight children ages 6 to 9 years) and was conducted among Australian children. The study’s authors made no attempt to evaluate the impact of gender on their results.