The Prevalence of Childhood Obesity in Adolescents

Overweight and Obesity levels have dramatically risen over the last fifty years across all corners of the world. This rise has led to the reclassification of Obesity to epidemic proportions. In 2008 1.4 billion adults aged 20 or over were classified as overweight with 500 million of these classified as Obese (WHO, 2008). A World Health Organization (WHO) report into childhood obesity in 2009 estimated that in 2010  43 million children under 5 would be overweight, with a staggering 35 million overweight/obese children in developing countries, and 8 million overweight or obese in developed countries (WHO, 2009).

WHO classifies Overweight and Obesity as a person having a Body Mass Index (BMI) of 25-29.9kg/m2 for Overweight and BMI of ≥30kg/m2 for Obese. A person falling within a range of 18-24.9kg/m2 is classified as normal weight. However, BMI for children and adolescents are defined differently than the BMI for adults. Unlike adult obesity, which increases slowly with age, childhood obesity rises steeply in infancy, falls during preschool, and rises again during adolescence. Overweight in children and adolescence is defined as a body mass index (BMI) of ≥85th percentile and Obese ≥ 95th percentile (F.M. Biro, M.Wien, 2010).

Until 2009, WHO recommended that BMI for children be assessed using age related reference curves. However, these curves were imperfect and the WHO recommended the British model of BMI for age and weight models, which adjust BMI for skewness and allows the BMI to be expressed as an exact centile or standard deviation score (WHO, 2000). The WHO has since developed a questionnaire style survey for monitoring weight gain in adolescents.  The Global School based Student Health Survey (GSHS) which was developed by the WHO and United States Centers for Disease  Control and Prevention. The survey is to help countries measure and assess 13-15 year olds health behavior. This questionnaire is low cost, which can obtain information in as many as 10 key areas that are known to be causes of mortality and morbidity (WHO, 2009). Many recent studies have used questionnaires to investigate the impact of overweight and obesity on children and adolescence.

One such study aimed to discover more about the dietary choices that adolescence make and whether it impacts on the subjects overweight and/or obesity problem. The study was carried out on the Social norms and diet in adolescents (P. Lally, N. Bertle, J. Wardle, 2011) with the aim of investigating the diet of adolescents as they often fall short of government health guidelines. The investigators recruited 264 school pupils aged between 16 and 19 years to complete a questionnaire their attitude to, intake of, and their peers attitude to and intake of fruit and vegetables, sugary drinks and unhealthy snacks. The investigators were able to ascertain that adolescents underestimated their peer’s intake of fruit and vegetables, over estimated their peers sugary drink and unhealthy snack food intake on a weekly basis. However, the respondents all agreed that eating five portions of fruit and vegetables a day was a good thing, they were less positive about the negative impact of sugary drinks and unhealthy snack food on their diet. Their perception of their peer’s attitude to fruit and vegetables was less positive than it actually was, while their perception of their peers attitude to fast food and sugary drinks was more positive than it actually was. Taking these factors into consideration, adolescent teens can be easily led by marketing and what they perceive to be the fashionable thing to eat and drink. It is possible that overweight and obese adolescents see unhealthy energy dense food a normal food choices that they and their peers would choose daily instead of healthy option meals.

A web based study carried out in Alberta, Canada also found that Overweight and Obese adolescents had significantly different nutritional intake, meal behavior and physical activity levels compared to their non overweight or obese peers (K.E. Storey, L.E. Forbes, S.N. Fraser, J.C. Spence, R.C. Plotnikoff, K.D. Raine, 2012). The researchers of the study concluded that significant differences exist between BMI classifications and meal intake and behavior towards meals. The investigators found that there was a need to target the food choices that led to a behavioral norm among the participants such as the consumption of high sugary soft drinks, total fat intake, breakfast skipping and low levels of physical activity among overweight and obese adolescents. Other Canadian studies found that the rate of obesity among adolescents has risen from 15% in 1978 to 29% in 2007, and is estimated that obesity among adults will rise to 70% by 2040 (childhoodobesityfoundation, 2010).

As adult obesity levels rise, data from developing industrial countries highlight the increased levels of obesity in children (B. Caballero, 2007). World Health Organization (2009) figures show that childhood obesity is increasing not only in developed countries (more than 8 million children diagnosed as overweight) but a growing problem in developing countries (35 million overweight children). Wang and Lobstein (2006) investigations into surveys carried out in 60 member states of the WHO analysis of subjects up to 18 years of age from papers published after 1980. The papers used weight and height or BMI to report the prevalence of Obesity in children. The authors reported a growing trend in all regions of the world of childhood obesity, especially in industrialized countries where the increase is very dramatic. The investigators concluded that if current trends continue on a linear basis than 46%of school going children will be overweight in the Americas, 41% in Eastern Mediterranean, 38% in the Europe Region, 27% in the Western Pacific, and 22% in South East Asia by 2010. It is expected that by 2015 that over 40% of US adults will be obese (Biro et al, 2010).

The National Health and Nutrition Surveys (NHANS) carried out in the United States over the last 20 years have shown that overweight and obesity in adolescence has doubled. In 1980 the prevalence of Overweight and Obesity was for children and adolescence between 2-19 years of age was 5.5%. In 2003-2006 survey 31% of children and adolescents aged between 2-19 years of age had a BMI at or above 85th percentile of the 2000 CDC BMI-for-age growth charts, and 16.3% were above the 95th percentile BMI for age.  A follow up study (Cynthia L. Ogden, Margaret D. Carroll, Brian K. Kit, Katherine M. Flegal, 2012) of the NHANS survey in 2010 showed that the prevalence of obesity among adolescences aged 12 to 19 years was 18.4%. Worryingly within this report 13.9% of the subjects had BMI levels of higher than 30. This doubling of overweight and obesity substantiates the study carried out by Garcia et al (2013) found that adolescent children between 12-16 years of age had an average obesity rate of 8.5% and an average overweight rate of 20.5%. This study could have been carried out in any country across Europe and the figures would be similar.

With this sudden rise in adult overweight and obesity, it is natural that there will be increased Obesity in children and adolescence, which is very prevalent across the developed world, and is increasing at an alarming rate. Foresight, A report commissioned by the British government in 2007, indicated that in Britain, average level of obesity in boys aged 11-15 will rise to 11% by 2025 and 23% by 2050, with adolescent boys under the age of 20 experiencing rates of 15% by 2025 and 25% by 2050. Girl’s aged 11-15 can expect an obese rate of 22% in 2025 and 35% in 2050. Adolescent girls under the age of 20 can expect increases of 15% in 2025 and 25% in 2050. Worryingly for policy makers in Britain, the authors of the report summarized that by 2050 70% of all girls could be overweight or obese with only 30% falling within the healthy BMI range. Boys would see a total 55% either overweight or obese with 45% falling within the healthy range (Foresight, 2007).

The rise in Obesity in both Britain and America tie in with the data from an Irish report entitled the growing up in Ireland study (2012), which reported that 20% of 13 year olds were overweight and 6% were obese. What was interesting about this study was the reporting that children at age 9 (89%) who were non-overweight were still normal weight at age 13. However, overweight (54%) and obese (just over 50%) 9 year olds were still overweight and at age 13. This would indicate that overweight and obese Irish children remained in that condition throughout their adolescent years into their adult years. If Irish adolescents follow the same path as their American counterparts we will see many more cases of Obesity above the 99th percentile (adult obesity is above 95th percentile) and into a category of extremely obese. Freedman (2007) reports that over 4% children and adolescents fall into this category. There are consequences both short and long term for obese children that will adversely affect their mental and physical health into adulthood (J.J. Reilly and J. Kelly, 2011).

Excess body fat in children is well documented as a risk factor for diseases that develop in adulthood along with the association of impaired and poor health during childhood. The risks to the health of an overweight or obese child include insulin resistance, increased risk of hypertension, and social distress. Once diagnosed, childhood obesity is rarely reversed. A systemic review (J.J. Reilly, J. Kelly, 2011) carried out a study on studies from 2002 to 2010 on the long-term impact of overweight and obesity in childhood and adolescence on morbidity and premature mortality in adulthood. The investigators found out of all the studies that 11 studies met their criteria. The study showed that 4/5 had a significantly increased risk of premature mortality with child and adolescent overweight or obesity. The investigators found that all studies associated increased risk of later cadiometabolic morbidity in adult life. The authors concluded that the body of evidence was consistent and reported that childhood obesity was linked to premature mortality and adult morbidity. While this study shows that there is a large body of evidence for linking overweight and obesity with morbidity, it does not look at the impact of childhood overweight and obesity on the long-term health implications of both the child and adult.

 One implication of adolescent Overweight and Obese adolescent individuals is that the long-term quality of life is drastically reduced. A study into the quality of life of adolescents was conducted on grades 7 to 12 in America, during 1994-5 school year (K.C. Swallen, E.N.Reitner, S.A. Haas, A.M. Meier, 2005). The investigators used the 1996 longitudinal study of Adolescent Health, which used a sample size of 4,743 subjects. Using height and weight as a measure and comparing the data from the subjects to growth charts. While the study covered many different aspects of obesity, the investigators found that Overweight and obese adolescents were more likely to report poor general health compared to their normal BMI peers.

Another important implication of obesity is Musculoskeletal disorders among overweight and obese children and adolescence, which is rising in line with the increase of childhood obesity (P.W. Esposito, P.Caskey, L.E. Heaton, N. Otsuka, 2013). This problem can lead to overweight and obese children avoiding exercise due to pain from over loaded joints. Esposito et al (2013) investigated the impact of musculoskeletal on overweight and obese children. The investigators found that the excess weight carried by the subjects had an impact on their joints. Subjects were found to have gait and alignment abnormalities and the stress particularly on the knee joint due to large thighs. The investigators reported that 39% of obese children (95th percentile) suffered from back pain, 24% with knee pain, and 26% with pain in the feet. These types of pain are normally associated with adults. However, these types of injuries are becoming more and more common among children and adolescence reducing their quality of life from a young age.

Weight gain and Obesity have been strongly associated with cardiovascular risk factors and cancer in recent years (Biro et al, 2012). A study into the long-term morbidity and mortality of overweight adolescents looked at the risk factors associated with this group after 55 years (A. Must, P.F. Jacques, G.E. Dallal, C.J.  Bajema, W.H. Dietz,1992). may represent the central deposition of adolescent body fat. The investigators reported that increased central body fat which affects a variety of cardiovascular risk factors. One impact of adolescent overweight was the impact of colorectal cancer, which increased the likelihood of morbidity if the subject was obese during their adolescent years. This, according to the investigators, was also the case with coronary heart disease, atherosclerosis, gout, and arthritis. The risk of a mortality from suffering from these diseases increased twofold among sufferers that were overweight or obese in their adolescent years compared to their lean counterparts. Unlike many studies, which are short term, this study was carried out over many years comprising of 508 persons and a total of 23,913 years of experience. The investigators concluded that that decrease in adolescent and childhood BMI figures was the most efficient form of reducing the associated morbidity and mortality in adults. Adolescents found that there was an association with an increase in a broad range of adverse health effects that were independent of adult weigh. This research ties in with other studies that were able to conclude that the effect of overweight in adolescent Obesity in children and adolescence has been strongly associated with Obesity in adults and studying childhood obesity is essential indentifying early signs of cardiovascular disease (D.Montaro, G, Walther, A. Perez-Martin, E. Roache and A. Vinet, 2011).

 Overweight and Obesity has been shown to be increasing at epidemic proportions among adolescents across the globe. There needs to be a firmer implementation of interventions by governments and health officials across the globe to ensure that future generations will not enter the healthcare system where they are almost guaranteed to have reduced quality of life and possibly reduced years. Data emerging from all countries and regions indicate that there is a major battle to reduce the overweight and obese levels among children and adolescents. Without tackling this problem it may become possible that parents outlive their children due to poor health caused by obesity during childhood and adolescent years.  It is important that individuals and governments take appropriate action to ensure that they implement certain interventions to reduce the risk of suffering from overweight and obesity and to ensure that their children do not suffer from the same disease.

Most of the interventions for family behavioral lifestyles have been set in a clinical program or environment, There are only a few studies into the lifestyle habits of adolescents, where less resource intensive treatment programs that would deal with long term maintenance of positive weight management programs (B. Nguyen, V.A Shewesbury, J. O’Conner, K.S. Steinbeck, A. Lee, A.J. Hill, S. Smita, M.R. Kohn, S. Torvaldsen, L.A. Baur, 2012). The Loozit weight management program is a community based weight management program for overweight and obese adolescence from 13 to 16 years of age.  The investigators (J. O’ Connor,  K. Steinbeck, A.Hill, M. Booth, M. Kohn, S.Shah, L. Bbaur, 2008) recruited 22 obese or overweight adolescence by way of press release, letters to principals, primary care physicians were informed. The investigators received 51 responses in 43% met the criteria. However, severely obese adolescence, or anyone with medical illnesses were excluded from the study. The study was to last for 5 months with sessions occurring weekly for the first month and then at two, four and five months. The participants completed questionnaires on diet, physical activity and self-esteem. The program focused on healthy eating, increased physical activity, decreasing sedentary lifestyle and increasing self-esteem. Attendance during the 5 months was around 91% at the weekly and monthly sessions. The investigators reported positive feedback form parents about the food choices that the children were making along with increased physical activity.

The results of the study showed that the participants showed a significant reduction in waist circumference, HDL cholesterol, physical appearance, and romantic appeal. There was however, no reduction in BMI or BMI z-scores, physical activity and sedentary lifestyle or dietary fat intake. More importantly, the low drop out rate of the study meant from a psychosocial it was a success. By encouraging overweight and obese adolescents to deal with their weight issues in a local setting, rather than bringing them to a clinical setting removes the stigma about their condition. From this study we can see that the self-esteem questionnaire showed an increase in the participants score for physical appearance from the start of the study (2.0) to the completion (2.2), P value of value of .048. The significance of this is greater confidence in what they are doing, and if the participants can see the benefit they are more likely to continue on this program of a similar style program. With greater motivation from the adolescent participants, this will also encourage parents to stick with the program as it also local, ensuring that their would be no need to travel great distances for access to the program and there would be more motivation to attend if it is in a local and a familiar setting.

 A second longitudal study of the Loozit program to assess the effect of additional therapeutic contact after 12 months (B. Nguyan et al, 2012). This study involved 151 obese 13-16 year olds. In the first 2 months (phase 1), adolescents attended weekly sessions that concentrated on lifestyle modification. These sessions were 75 minutes in duration and adolescents and parents had separate sessions. In phase 2 (2-24 months) the participants attended a booster session every 3 moths during each school term. Participants in this study were divided into tow study arms. One study arm received Loozit support. The second arm of the study received support from Loozit and received Additional Therapeutic Contact (ATC) once a fortnight in the form of either telephone, e-mail or text message. For the duration of the study, there was a high attendance rate (82.1%) for 70% or more of the sessions. The investigators found significant reduction in mean body mass index (-.09), waist to height (-0.02), total cholesterol (-4mg/dL) and triglycerides (-80mg/dL). The self-esteem of the participants also increased with mental health (-.97, P=0.01), body shape dissatisfaction (-0.57, P=0.01), global self-worth (0.21, P,≤0.01).

 The investigators only had a small group to work with in the first study, given the nature of the study it was likely that large scale changes would take longer than 5 months to become noticeable, especially in a small study like this. This can be seen in study 2 where we see a reduction in BMI, waist to height, total triglycerides and cholesterol.  Both studies highlight the increase in self-esteem, mental health and body dissatisfaction. Even if there are no large-scale differences in weight reduction, the positive mental impact of these studies makes the process of the community-based program worthwhile. It can seen that the habits that the subjects had developed with regards food consumption and physical activity, would not change overnight and would take a certain period of time to become normal behavior. The investigators at the end of the five month study reported no significant decrease in dietary fat intake, nor was there a significant increase in physical activity by the participants, nor was there any reporting of significant decrease in sedentary activities such as watching television or computer use. However, there evidence for a behavioral change, which was identified by the researchers after 12 months whereby participants reported less frequent consumption of high fat meat products, less consumption of potato chips, and less time spent either in front of a computer screen or watching television (Nguyan et al, 2012).

 This program was developed to deal with family behavior within the local community. By addressing family behavior in this setting the loozit program was more successful on psychosocial basis than on actual weight loss. By getting families to think about what they are eating, how much they are eating, what type of physical activity they are doing, how much sedentary time is spent not doing anything, will have a greater effect over the long term than over the course of this study. The investigators used the feedback of the questionnaires after the first study and implemented them for the second study, thus we can see the benefits to a longer run program. What neither program addressed was the actual health of the participants in each study. It would have been beneficial for further studies and likeminded programs if there were evidence of increased health such less sick days from school, less respatory problems and other illnesses that are associated with overweight and obesity. It is well documented that overweight and obesity is linked to numerous health problems in adults. A study into the endothelial dysfunction, inflammation, and oxidative stress in obese children and adolescence (D, Montero, G. Walther, A. Perez-Martin, E. Roche, A. Vinet, 2011). The researchers reported from the data they collected from numerous studies that endothelial dysfunction, inflammation and oxidative stress are well documented in obese children. The investigators concluded that therapeutic strategies such as lifestyle interventions such as diet and physical activity in early childhood obesity could potentially reverse the endothelial dysfunction.

These studies highlight the benefits of programs like Loozit, and the results they can achieve for overweight and obese children. It is not always important to achieve huge results when dealing with weight loss, as small results over a long period of time can have as much benefit to subjects who are overweight or obese. From a healthcare point of view, lowering the risk of these children needing long-term medication and increasing their quality of life that will reduce the stress on increasing their reliance on a government healthcare system for a variety of illnesses associated with overweight and obesity.


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