What is BMI and what is the evidence behind its application in assessing childhood obesity?

There is now controversy regarding the use of BMI when diagnosing children as being overweight. Cowie (2014) notes that athletic children are sometimes mistakenly diagnosed as being overweight, when there is no distinguishing between fat tissue, bone tissue, and lean muscle mass. The author also suggests that adding waist circumference to the measurement is a better predictive indicator of other future cardiovascular comorbidities (diabetes, coronary artery disease, etc.). Cowie (2014) also notes that the BMI chart does not take a child's stage of development into consideration.

Historically, a healthy weight for a child was based on BMI:

- Overweight: BMI 85^th to <95^th percentile

- Obese:  BMI > 95^th percentile

(Cowie, 2014)

Given the controversy surrounding the use of BMI, do you think BMI is still the best tool for assessing childhood obesity?

Reference:

Cowie, J. (2014). Measure of Obesity in Children. Primary Health Care,  

     24(7), 18-23.

What is the role of physical activity in reducing childhood obesity?

It is no secret that childhood obesity is curbed when programs are available to promote proper dietary habits and increased physical activity. Farley and Dowell (2014) note that between 50% and 90% of adolescents do not engage in the government’s definition of appropriate physical activity.  The authors conducted a study in New York City that evaluated the prevalence of childhood obesity in public school children when they participated in supplemental nutrition and physical activity programs.

(New York Department of Health, 2014)

The above graph notes a decline in the percentage of childhood obesity in school children of all ages In New York City over time. The authors suggest the decline is attributed to the elimination of vending machines, decreases in the amount and types of foods consumed, increased physical activity, and food marketing and packaging (Farley and Dowell, 2014).

Reference:

Farley, T. A., & Dowell, D. (2014). Preventing childhood obesity: What are we doing  

     right?. American Journal Of Public Health, 104(9), 1579-1583.

What is the role of nutrition in reducing childhood obesity?

During the first five years of life infants start developing eating habits by watching adults especially their mothers. In many cases eating habits are also influenced by social settings within a cultural context.

Studies have found that only 1% of children meet the recommended dietary allowances while 50% of children have diets too high in fat and sugar. A possible solution to decrease fat and sugar intake is to increase the consumption of fruits and vegetables.

Birch (1998) recommends that parents teach their children healthy eating choices rather than dieting. It has been found that mothers who attempt to restrict food availability are not teaching healthy eating habits that encourage food selections that are low in fat and sugar. Food restrictions may cause binge eating when the mother is not with the child.

To promote healthy eating habits parents should introduce children to a wide variety of foods early in life. Young children who have only been exposed to a diet with few choices may develop food phobia later in childhood (Birch, 1998).

Parents can utilize a Traffic Light method to teach children healthy eating choices. Green light foods are low in caloric intake and can be eaten freely. Yellow Light food should only been occasionally due to higher being higher in calories. Red Light foods are unhealthy and should only be consumed on rare occasions (Ho et al., 2012).

References:

Birch, L. L. (1998). Developmenet of food acceptance patterns in the first years of life.     Proceedings of the Nutrition Society, 57, 617-624.

Ho, M., Garnett, S. P., Baur, L., Burrows, T., Stewart, L., Veve, M., & Collins, C. (2012). Effectiveness of lifestyle interventions in child obesity: Systematic review with meta-analysis. American Academy of Pediatrics, 130 (6), E1647- E1671.

What are the dangers associated with childhood obesity?

In the last 30 years, childhood obesity has tripled from approximately 5 to 15 percent (Ogden, Carroll, Kit, & Flegal, 2014). This dramatic increase has long term ramifications on individual health, often being the causative factor associated to chronic conditions lasting well into adulthood.

Source: Ogden, C. L., Carroll, M. D., Kit, B. K., & Flegal, K. M. (2014)

Unfortunately, childhood obesity has many health consequences, including increased incidence of type II diabetes and cardiovascular disease, resulting in early morbidity (Freedman, Mei, Srinivasan, Berenson, & Dietz, 2007).

Children who are obese at age two are greater than 50% more likely to be an obese adult (Freedman, et al., 2005).

Childhood obesity increases lifetime healthcare costs; an obese 10-year old has approximately 55% higher healthcare costs than a peer of the same age with a normal BMI (Finkelstein, Wan Chen Kang, & Malhotra, 2014).

References

Finkelstein, E. A., Wan Chen Kang, G., & Malhotra, R. (2014). Lifetime direct medical costs of childhood obesity. Pediatrics, 133(5), 854 - 862.

Freedman, D. S., Mei, Z., Srinivasan, S. R., Berenson, G. S., & Dietz, W. H. (2007). Cardiovascular risk factors and excess adiposity among overweight children and dolescent: The Bogalusa heart study. The Journal of Pediatrics, 150(1),12 - 17.

Ogden, C. L., Carroll, M. D., Kit, B. K., & Flegal, K. M. (2014). Prevalence of childhood and adult obesity in the United States, 2011 - 2012. Journal of the American Medical Association, 311(8), 806 - 814.

What can parents do to reduce childhood obesity?

Get involved, Participate in Physical Activity: Households where parents seldom engage in physical activity, negatively affect the frequency of childhood obesity. Erkelenz et al, (2014) found a reduction in obesity rates when the mothers of obese children where actively involved in their child’s physical activity, with greater benefits obtained when both parents were involved leading healthy, active lifestyles.

Limit Screen Time: Van Biljon and Longhurst (2012), showed a positive correlation between exergaming and weight loss in adolescents. Getting children and adolescents involved in any, physical activity is beneficial. The only concern is if screen time becomes more of a sedentary style of “gaming” where there is no physical exertion at all. A study evaluating possible correlations between electronic use and obesity were conducted by Wethington, Pan, and Sherry (2013). Findings indicated that 20.8% to 26.1 percent of children aged 6 to 17-year-olds had excessive screen time which contributed to an increase in study population BMI. (Wethington, Pan, & Sherry, 2013).

Parents, Pack your child’s lunch: There is evidence to suggest that parents can help to reduce obesity or the risk of obesity by packing their child's lunch for school, and avoiding the inclusion of processed foods in their child's diet.

Source: Valentine's lunchbox ideas for the family (2015)

Bray et al. (2004) explored the relationship between the obesity epidemic and intake of high fructose corn syrup (HFCS) in sweetened beverages. When this article was published, HFCS represented over 40% of caloric sweeteners added to foods and beverages. The consumption of HFCS increased over 1000% between 1970 and 1990, and the increasing obesity problem paralleled this increase.

Source: Bray, Nielsen, & Popkin (2004)

References

Bray, G. A., Nielsen, S. J., & Popkin, B. M. (2004). Consumption of high-fructose corn syrup in beverages may play a role in the epidemic of obesity. American Journal of Clinical Nutrition, 79(4), 537 – 543.

Erkelenz, N., Kobel, S., Kettner, S., Drenowatz, C., & Steinacker, J. M. (2014). Parental Activity as Influence on Children`s BMI Percentiles and Physical Activity. Journal of Sports Science & Medicine, 13(3), 645-650.

Van biljon, a., & longhurst, g. K. (2012). The influence of exergaming on the functional fitness in overweight and obese children. African Journal for Physical, Health Education, Recreation & Dance, 18(4), 984-991.

Wethington, H., Pan, L., & Sherry, B. (2013). The Association of Screen Time, Television in the Bedroom, and Obesity Among School-Aged Youth: 2007 National Survey of Children's Health. Journal of School Health, 83(8), 573-581.