- Email: [email protected]
Relationship between summer vacation weight gain and lack of success in a pediatric weight control program
Eating Behaviors 6 (2005) 137 – 143
Relationship between summer vacation weight gain and lack of success in a pediatric weight control program Linda Gillis*, Melissa McDowell, Oded Bar-Or Children’s Exercise and Nutrition Centre, Evel 4, Room 464A, Chedoke Division, HHS, Hamilton, Ontario, Canada L8N 3Z5 Received 29 April 2004; accepted 31 August 2004
Abstract The purpose was to measure the effect of holidays or season on changes in body weight to determine if this was the reason for the low success rate of weight control program participants. Changes in percent ideal body weight were gathered on 73 overweight youth (average age: 10.5F2.8 years; percent ideal body weight: 150F28%) over 2-month intervals in a 1-year time span. There was a statistically significant gain in percentage of body weight during July–August compared to January–February at pb0.004, March–April at pb0.04, May–June at pb0.001 and September–October at pb0.04. Sixty-six percent of subjects gained weight during the summer months. When the subjects who lost weight in the summer period were removed from the analysis, the average weight gain was 2.8% of ideal body weight. For a weight control program for children and adolescents to be effective, strategies need to be developed to deal with the summer vacation period as this can affect the overall success in the program. D 2004 Elsevier Ltd. All rights reserved. Keywords: Pediatric; Weight control; Weight loss; Holidays
1. Introduction Obesity is becoming a worldwide problem and is being described as an epidemic (World Health Organization, 1998). Between 1981 and 1996 in Canada, the prevalence of overweight (BMI greater than the 85th percentile for age and sex) among boys increased from 15% to 35.4% and among girls from 15% to 29.2%. The prevalence of obesity (BMI greater than the 95th percentile for age and sex) in * Corresponding author. Tel.: +1 905 521 2100x74193; fax: +1 905 385 5033. E-mail address: [email protected] (L. Gillis). 1471-0153/$ - see front matter D 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.eatbeh.2004.08.002
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L. Gillis et al. / Eating Behaviors 6 (2005) 137–143
children more than tripled over that time, from 5% to 16.6% for boys and 14.6% for girls (Tremblay & Willms, 2000). Clinical weight control programs and research studies have had varied success in the treatment of juvenile obesity. Overall, the amount of weight loss is minimal and patients or subjects have not been able to reach their ideal body weight. The programs that have the most success usually last a short time span such as 3 to 6 months. The maintenance of the lower body weight over a longer time span, such as 1 year, has only been shown in a few studies (Epstein, Myers, Raynor, & Saelens, 1998). In healthy adults, there is a slight increase in weight over time, with the average weight gain ranging from 0.2 to 0.8 kg/year (Yanovski et al., 2000). A few research groups have found that there is a gain in weight over holiday times such as Christmas and Thanksgiving which may contribute to this overall annual gain (Andersson & Rossner, 1992; Boutelle, Kirschenbaum, Baker, & Mitchell, 1999; Yanovski et al., 2000). A study by Yanovski et al. (2000) on 195 American adults found that an average weight gain of 0.48 kg occurred during fall and winter (the Thanksgiving and Christmas holiday time), and this gain was not reversed during spring or summer, which contributed to the overall yearly weight gain. There was a trend towards a greater likelihood of significant weight gain as the degree of overweight increased. In a supervised diet program with obese adults, the subjects lost more weight in the spring compared to the winter season (Zahorska-Markiewicz, 1980). Healthy children gain weight throughout the year as part of growth and development, but there are seasonal variations with even greater weight gain seen in autumn (Attarzadeh, 1983). It has never been shown in weight loss programs designed for children or adolescents whether the same seasonal weight gain trend occurs. Therefore the purpose of this study was to determine the effects of season or holidays on changes in body weight in overweight children and adolescents. We hypothesized that the subjects would gain more weight, as percentage of their ideal body weight, at certain periods of the year that could contribute to an overall lower success rate in a weight control program.
2. Methods 2.1. Subjects The participants were patients of the Children’s Exercise and Nutrition Centre and were defined as obese if they had a BMI greater than the 95th percentile of the reference values for age and sex (Kuczmarski et al., 2000). The centre treats approximately 150 new obese children and adolescents per year and uses an interdisciplinary behavior modification approach to the treatment of juvenile obesity. The children were seen monthly. Behavioral strategies included goal setting, self-monitoring, positive reinforcement and nutrition and exercise education. The children were not placed on diets or did not participate in a structured activity program, but instead set small incremental goals to change their lifestyles. A total of 73 subjects were included in this retrospective study. Those with eating disorders, genetic disorders of obesity, physical limitations, other co-morbid conditions or on medications that may affect appetite or activity were excluded. Those with a major sickness during the year that involved vomiting or a prolonged decrease in appetite were also excluded. To be eligible, the subjects could not have missed more than one monthly appointment during the year. Fifty-one of the subjects attended all sessions and the other 22 missed one appointment only. The results were not different between those who missed one appointment and those who attended every visit, thus the data were combined for the 73 subjects.
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2.2. Measurements Basic demographic material was obtained including age, gender, ethnic group and income level. At each visit, standing height was measured in stocking feet using a Harpenden Stadiometer (London, UK) with a precision of 0.1 cm. Weight was measured to the nearest 10 g in a standard hospital gown or tshirt and shorts using an Ancaster electronic scale (Brantford, Ontario). To determine the percent ideal body weight, weight was divided by the ideal body weight for age, height and sex and then multiplied by 100. For analysis, the year of treatment was divided into six distinct time periods based on holidays, and subjects were recruited as equally as possible from each of the six time periods. These included: period 1 (January–February), period 2 (March–April), period 3 (May–June), period 4 (July–August), period 5 (September–October) and period 6 (November–December). Data were collected after the subjects had spent 2 months in the program as the first 2 months were used mainly for assessment by the different therapists, and significant changes in physical activity, nutrition and weight begin to occur after this point. As the subjects did not come at equal intervals between visits, the data were adjusted by dividing the weight change by the number of days between measurements. Display of the data is by period so the weight changes were then standardized by multiplying by 60 (the number of days in each period). 2.3. Statistical analysis To determine if there were differences between the changes in percent ideal body weight in each time period, a one-way analysis of variance was run with the Student–Newman–Keuls statistic for pairwise multiple comparisons. Results were considered significant at pb0.05. To determine if their was an age effect, the subjects were divided into two age groups and a Chi-Square test was run. These included an adolescent group ages 12 to 16 years and a pre-adolescent group ages 5 to 11 years. Gender effects were also determined by Chi-Square.
3. Results The subjects were all Caucasian and from various socioeconomic levels but the majority were middle class families (net earning of $20,000 to $49,000 Canadian). There were 40 females and 33 males with the average age at 10.5F2.8 years. They had an average weight of 64F23 kg, average percent of ideal weight of 150F28% and average height of 147F15 cm. There were no gender or age related effects so results pertain to the whole group. As displayed in Fig. 1, there was a statistically significant gain in percentage of body weight during period 4 (July–August) compared to period 1 (January–February) at pb0.004, period 2 (March–April) at pb0.04, period 3 (May– June) at pb0.001 and period 5 (September–October) at pb0.04. Fig. 2 lists the percentage of children who lost weight in each time period. On average, 52% to 67% of the subjects lost weight in each time period except for Period 4, in which only 34% lost weight. The average weight gain in Period 4 (July–August) was 0.67% of ideal body weight with a range of +12.2% to 11.3% of ideal body weight. When the subjects who lost weight in Period 4 (34% of the participants) were removed from the analysis, the average weight gain was 2.8% of ideal body weight.
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Fig. 1. Percent weight change in each time period. Data represented in mean and standard error of the mean. The subjects gained significantly more weight in the summer months (Period 4) compared to other seasons at pb0.05 except the Halloween/ Christmas season (Period 6).
Fig. 2. Percentage of subjects who lost weight as a percentage of ideal over each time period. The percentage of subjects who lost weight in the summer months was less than in other months.
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4. Discussion Children and adolescents in a multidisciplinary, behavioral weight control program gained significantly more weight during the summer months and that contributed to an overall lower success rate in the program. Sixty-six percent of participants gained weight during this summer vacation time, and their gain was almost 3% of ideal body weight. There are many factors that could have contributed to this significant weight gain seen in the summer months such as an increase in sedentary time, increase in situations that cause overeating, increase in availability of higher calorie foods, under-arousal leading to overeating and finally a failure to selfmonitor the required dietary and activity changes as discussed below. The increase in weight seen in the summer months in our subjects was likely not related to a decrease in activity. Children have been shown to increase activity levels in the summer because of the increase in time spent outdoors (Sallis, Prochaska, & Taylor, 2000). This increase in activity does not account for the reported increase in sedentary time seen during the summer hiatus from school. Sedentary activities such as television watching, video games and computers are associated with increased levels of body fatness (Andersen, Crespo, Bartlett, Cheskin, & Pratt, 1998). Conversely, if television time is decreased, a lower increase in body mass index occurs and the number of meals eaten in front of the television decreases (Robinson, 1999). This is important because eating in front of the television is associated with consumption of higher calorie foods (Foreyt & Cousins, 1989). Television commercials play a role in what foods parents bring into the home. There is a link between the number of hours of television watched, children’s requests of advertised foods and the willingness of parents to purchase foods requested by children. The most advertised foods are higher calorie items such as candies, snacks, prepared convenience foods and soft drinks. Fruits and vegetables are the least advertised foods (French, Story, & Jeffery, 2001). The more minutes or hours of advertising a person is exposed to, the more likely that person is to purchase and consume the advertised food (Coon, Goldberg, Rogers, & Tucker, 2001). Family celebrations, socializing and relaxation situations have been shown to lead to relapses in dieting behaviour in overweight adults (Drapkin, Wing, & Shiffman, 1995; Grilo, Shiffman, & Wing, 1989). Individuals have the most difficulty coping when eating in larger group settings. As there are more family gatherings such as camping trips and barbeques in the summer, this is likely a difficult time for children. This higher availability of preferred foods and increase in food variety in the summer could lead to weight gain, as it is known that highly palatable foods are consumed in greater amounts (Roberts, 2000). In fact, it has been shown that in an adult weight control program, 73% of relapse crises are precipitated by food stimuli (Grilo et al., 1989). One food item that has been reported by patients to increase considerably during the warmer summer months is sugar-sweetened drinks and this consumption is correlated with adiposity (Gillis & Bar-Or, 2003). In another study by Ludwig, Peterson, and Gortmaker (2001), the authors followed 548 school children over a 2-year time span, and found that for each serving of sugar-sweetened drink consumed, body mass index and frequency of obesity increased. The reason for this may be related to the failure of the children to decrease their intake at subsequent meals. The drinks may have added to the calories consumed instead of displacing energy from solid forms (Mattes, 1996). States of under-arousal can lead to overeating. In adults, relapses in dieting occur while relaxing, waiting or when in between activities (Grilo et al., 1989). Without the daily schedule of school, children will have more idle time that could lead to overeating. Children at our centre often cite boredom as one of the main reasons for searching for food in the summer.
142
L. Gillis et al. / Eating Behaviors 6 (2005) 137–143
A successful technique often used in weight control programs is self-monitoring, and adults who keep records have been shown to lose 64% more weight than those who do not self-monitor (Sperduto, Thompson, & O’Brien, 1986). Many of our patients failed to keep records of their activity and nutrition goals during the summer months compared with the school year. This could also explain some of the weight gain during the summer. The earliest reports of seasonal variations in weight and height in healthy children originated in the early 1900s. The rate of weight gain was greatest in the autumn (Attarzadeh, 1983). Since that time, the growth patterns of thousands of male and female children well nourished, supplemented and malnourished have been well documented and similar trends in seasonal growth rates have been found. This is true at all ages after the first year, including the adolescent pubertal period (Tanner, 1977). Thus this also underscores that the increase in weight in the summer vacation was likely due to changes in their eating or exercise patterns or both. In conclusion, for a weight control program in obese children and adolescents to be successful, strategies need to be developed to deal with the summer vacation period. The pattern of weight gain is different from that seen in adults. Families need to be aware that there are more stimuli present for children during the summer that lead to overeating. The environmental cues that cause an increase in eating and in sedentary time need to be recognized and overcome by the child and the whole family unit.
References Andersen, R. E., Crespo, C. J., Bartlett, S. J., Cheskin, L. J., & Pratt, M. (1998). Relationship of physical activity and television watching with body weight and level of fatness among children. Journal of the American Medical Association, 279, 938 – 942. Andersson, I., & Rossner, S. (1992). The Christmas factor in obesity therapy. International Journal of Obesity, 16, 1013 – 1015. Attarzadeh, F. (1983). Seasonal variation in stature and body weight. International Journal of Orthodontics, 21, 3 – 12. Boutelle, K. N., Kirschenbaum, D. S., Baker, R. C., & Mitchell, M. E. (1999). How can obese weight controllers minimize weight gain during the high risk holiday season? By self-monitoring very consistently. Health Psychology, 18, 364 – 368. Coon, K. A., Goldberg, J., Rogers, B. L., & Tucker, K. L. (2001). Relationships between use of television during meals and children’s food consumption patterns. Pediatrics, 107, E7. Drapkin, R. G., Wing, R. R., & Shiffman, S. (1995). Responses to hypothetical high risk situations: Do they predict weight loss in a behavioral treatment program or the context of dietary lapses. Health Psychology, 14, 427 – 434. Epstein, L. H., Myers, M. D., Raynor, H. A., & Saelens, B. E. (1998). Treatment of pediatric obesity. Pediatrics, 101, 554 – 570. Foreyt, J. P., & Cousins, J. H. (1989). Obesity. In E. J. Mash, & R. A. Barkley (Eds.), Treatment of childhood disorders (pp. 405 – 422). New York7 The Guilford Press. French, S. A., Story, M., & Jeffery, R. W. (2001). Environmental influences on eating and physical activity. Annual Review of Public Health, 22, 309 – 335. Gillis, L. J., & Bar-Or, O. (2003). Food away from home, sugar-sweetened drink consumption and juvenile obesity. Journal of the American College of Nutrition, 22, 539 – 545. Grilo, C. M., Shiffman, S., & Wing, R. R. (1989). Relapse crises and coping among dieters. Journal of Consulting and Clinical Psychology, 57, 488 – 495. Kuczmarski, R. J., Ogden, C. L., Grummer-Strawn, L. M., Flegal, K. M., Guo, S. S., Wei, R., et al. (2000). CDC growth charts. Advance Data from Vital and Health Statistics, 314, 1 – 28. Ludwig, D. S., Peterson, K. E., & Gortmaker, S. L. (2001). Relation between consumption of sugar-sweetened drinks and childhood obesity: A prospective, observational analysis. Lancet, 357, 505 – 508. Mattes, R. D. (1996). Dietary compensation by humans for supplemental energy provided as ethanol or carbohydrate in fluids. Physiology and Behavior, 59, 179 – 187. Roberts, S. B. (2000). Holiday weight gain: Fact or fiction. Nutrition Reviews, 58, 378 – 379.
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Robinson, T. N. (1999). Reducing children’s television viewing to prevent obesity. Journal of the American Medical Association, 282, 1561 – 1567. Sallis, J. F., Prochaska, J. J., & Taylor, W. C. (2000). A review of correlates of physical activity of children and adolescents. Medicine and Science in Sports and Exercise, 32, 963 – 975. Sperduto, W. A., Thompson, H. S., & O’Brien, R. M. (1986). The effect of target behaviour monitoring on weight loss and completion rate in a behavioral modification program for weight reduction. Addictive Behaviors, 11, 337 – 340. Tanner, J. M. (1977). Education and physical growth. London7 Hodder and Stoughton. Tremblay, M. S., & Willms, J. D. (2000). Secular trends in the body mass index of Canadian children. Canadian Medical Association Journal, 163, 1429 – 1433. World Health Organization, 1998. Global prevalence and secular trends in obesity In Report of a WHO consultation on obesity, Obesity preventing and managing the global epidemic (pp. 17–40), Geneva. Yanovski, J. A., Yanovski, S. Z., Sovik, K. N., Nguyen, T. T., O’Neil, P. M., & Sebring, N. G. (2000). A prospective study of holiday weight gain. New England Journal of Medicine, 342, 861 – 867. Zahorska-Markiewicz, B. (1980). Weight reduction and seasonal variation. International Journal of Obesity, 4, 139 – 143.
Relationship between summer vacation weight gain and lack of success in a pediatric weight control program Linda Gillis*, Melissa McDowell, Oded Bar-Or Children’s Exercise and Nutrition Centre, Evel 4, Room 464A, Chedoke Division, HHS, Hamilton, Ontario, Canada L8N 3Z5 Received 29 April 2004; accepted 31 August 2004
Abstract The purpose was to measure the effect of holidays or season on changes in body weight to determine if this was the reason for the low success rate of weight control program participants. Changes in percent ideal body weight were gathered on 73 overweight youth (average age: 10.5F2.8 years; percent ideal body weight: 150F28%) over 2-month intervals in a 1-year time span. There was a statistically significant gain in percentage of body weight during July–August compared to January–February at pb0.004, March–April at pb0.04, May–June at pb0.001 and September–October at pb0.04. Sixty-six percent of subjects gained weight during the summer months. When the subjects who lost weight in the summer period were removed from the analysis, the average weight gain was 2.8% of ideal body weight. For a weight control program for children and adolescents to be effective, strategies need to be developed to deal with the summer vacation period as this can affect the overall success in the program. D 2004 Elsevier Ltd. All rights reserved. Keywords: Pediatric; Weight control; Weight loss; Holidays
1. Introduction Obesity is becoming a worldwide problem and is being described as an epidemic (World Health Organization, 1998). Between 1981 and 1996 in Canada, the prevalence of overweight (BMI greater than the 85th percentile for age and sex) among boys increased from 15% to 35.4% and among girls from 15% to 29.2%. The prevalence of obesity (BMI greater than the 95th percentile for age and sex) in * Corresponding author. Tel.: +1 905 521 2100x74193; fax: +1 905 385 5033. E-mail address: [email protected] (L. Gillis). 1471-0153/$ - see front matter D 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.eatbeh.2004.08.002
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L. Gillis et al. / Eating Behaviors 6 (2005) 137–143
children more than tripled over that time, from 5% to 16.6% for boys and 14.6% for girls (Tremblay & Willms, 2000). Clinical weight control programs and research studies have had varied success in the treatment of juvenile obesity. Overall, the amount of weight loss is minimal and patients or subjects have not been able to reach their ideal body weight. The programs that have the most success usually last a short time span such as 3 to 6 months. The maintenance of the lower body weight over a longer time span, such as 1 year, has only been shown in a few studies (Epstein, Myers, Raynor, & Saelens, 1998). In healthy adults, there is a slight increase in weight over time, with the average weight gain ranging from 0.2 to 0.8 kg/year (Yanovski et al., 2000). A few research groups have found that there is a gain in weight over holiday times such as Christmas and Thanksgiving which may contribute to this overall annual gain (Andersson & Rossner, 1992; Boutelle, Kirschenbaum, Baker, & Mitchell, 1999; Yanovski et al., 2000). A study by Yanovski et al. (2000) on 195 American adults found that an average weight gain of 0.48 kg occurred during fall and winter (the Thanksgiving and Christmas holiday time), and this gain was not reversed during spring or summer, which contributed to the overall yearly weight gain. There was a trend towards a greater likelihood of significant weight gain as the degree of overweight increased. In a supervised diet program with obese adults, the subjects lost more weight in the spring compared to the winter season (Zahorska-Markiewicz, 1980). Healthy children gain weight throughout the year as part of growth and development, but there are seasonal variations with even greater weight gain seen in autumn (Attarzadeh, 1983). It has never been shown in weight loss programs designed for children or adolescents whether the same seasonal weight gain trend occurs. Therefore the purpose of this study was to determine the effects of season or holidays on changes in body weight in overweight children and adolescents. We hypothesized that the subjects would gain more weight, as percentage of their ideal body weight, at certain periods of the year that could contribute to an overall lower success rate in a weight control program.
2. Methods 2.1. Subjects The participants were patients of the Children’s Exercise and Nutrition Centre and were defined as obese if they had a BMI greater than the 95th percentile of the reference values for age and sex (Kuczmarski et al., 2000). The centre treats approximately 150 new obese children and adolescents per year and uses an interdisciplinary behavior modification approach to the treatment of juvenile obesity. The children were seen monthly. Behavioral strategies included goal setting, self-monitoring, positive reinforcement and nutrition and exercise education. The children were not placed on diets or did not participate in a structured activity program, but instead set small incremental goals to change their lifestyles. A total of 73 subjects were included in this retrospective study. Those with eating disorders, genetic disorders of obesity, physical limitations, other co-morbid conditions or on medications that may affect appetite or activity were excluded. Those with a major sickness during the year that involved vomiting or a prolonged decrease in appetite were also excluded. To be eligible, the subjects could not have missed more than one monthly appointment during the year. Fifty-one of the subjects attended all sessions and the other 22 missed one appointment only. The results were not different between those who missed one appointment and those who attended every visit, thus the data were combined for the 73 subjects.
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2.2. Measurements Basic demographic material was obtained including age, gender, ethnic group and income level. At each visit, standing height was measured in stocking feet using a Harpenden Stadiometer (London, UK) with a precision of 0.1 cm. Weight was measured to the nearest 10 g in a standard hospital gown or tshirt and shorts using an Ancaster electronic scale (Brantford, Ontario). To determine the percent ideal body weight, weight was divided by the ideal body weight for age, height and sex and then multiplied by 100. For analysis, the year of treatment was divided into six distinct time periods based on holidays, and subjects were recruited as equally as possible from each of the six time periods. These included: period 1 (January–February), period 2 (March–April), period 3 (May–June), period 4 (July–August), period 5 (September–October) and period 6 (November–December). Data were collected after the subjects had spent 2 months in the program as the first 2 months were used mainly for assessment by the different therapists, and significant changes in physical activity, nutrition and weight begin to occur after this point. As the subjects did not come at equal intervals between visits, the data were adjusted by dividing the weight change by the number of days between measurements. Display of the data is by period so the weight changes were then standardized by multiplying by 60 (the number of days in each period). 2.3. Statistical analysis To determine if there were differences between the changes in percent ideal body weight in each time period, a one-way analysis of variance was run with the Student–Newman–Keuls statistic for pairwise multiple comparisons. Results were considered significant at pb0.05. To determine if their was an age effect, the subjects were divided into two age groups and a Chi-Square test was run. These included an adolescent group ages 12 to 16 years and a pre-adolescent group ages 5 to 11 years. Gender effects were also determined by Chi-Square.
3. Results The subjects were all Caucasian and from various socioeconomic levels but the majority were middle class families (net earning of $20,000 to $49,000 Canadian). There were 40 females and 33 males with the average age at 10.5F2.8 years. They had an average weight of 64F23 kg, average percent of ideal weight of 150F28% and average height of 147F15 cm. There were no gender or age related effects so results pertain to the whole group. As displayed in Fig. 1, there was a statistically significant gain in percentage of body weight during period 4 (July–August) compared to period 1 (January–February) at pb0.004, period 2 (March–April) at pb0.04, period 3 (May– June) at pb0.001 and period 5 (September–October) at pb0.04. Fig. 2 lists the percentage of children who lost weight in each time period. On average, 52% to 67% of the subjects lost weight in each time period except for Period 4, in which only 34% lost weight. The average weight gain in Period 4 (July–August) was 0.67% of ideal body weight with a range of +12.2% to 11.3% of ideal body weight. When the subjects who lost weight in Period 4 (34% of the participants) were removed from the analysis, the average weight gain was 2.8% of ideal body weight.
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Fig. 1. Percent weight change in each time period. Data represented in mean and standard error of the mean. The subjects gained significantly more weight in the summer months (Period 4) compared to other seasons at pb0.05 except the Halloween/ Christmas season (Period 6).
Fig. 2. Percentage of subjects who lost weight as a percentage of ideal over each time period. The percentage of subjects who lost weight in the summer months was less than in other months.
L. Gillis et al. / Eating Behaviors 6 (2005) 137–143
141
4. Discussion Children and adolescents in a multidisciplinary, behavioral weight control program gained significantly more weight during the summer months and that contributed to an overall lower success rate in the program. Sixty-six percent of participants gained weight during this summer vacation time, and their gain was almost 3% of ideal body weight. There are many factors that could have contributed to this significant weight gain seen in the summer months such as an increase in sedentary time, increase in situations that cause overeating, increase in availability of higher calorie foods, under-arousal leading to overeating and finally a failure to selfmonitor the required dietary and activity changes as discussed below. The increase in weight seen in the summer months in our subjects was likely not related to a decrease in activity. Children have been shown to increase activity levels in the summer because of the increase in time spent outdoors (Sallis, Prochaska, & Taylor, 2000). This increase in activity does not account for the reported increase in sedentary time seen during the summer hiatus from school. Sedentary activities such as television watching, video games and computers are associated with increased levels of body fatness (Andersen, Crespo, Bartlett, Cheskin, & Pratt, 1998). Conversely, if television time is decreased, a lower increase in body mass index occurs and the number of meals eaten in front of the television decreases (Robinson, 1999). This is important because eating in front of the television is associated with consumption of higher calorie foods (Foreyt & Cousins, 1989). Television commercials play a role in what foods parents bring into the home. There is a link between the number of hours of television watched, children’s requests of advertised foods and the willingness of parents to purchase foods requested by children. The most advertised foods are higher calorie items such as candies, snacks, prepared convenience foods and soft drinks. Fruits and vegetables are the least advertised foods (French, Story, & Jeffery, 2001). The more minutes or hours of advertising a person is exposed to, the more likely that person is to purchase and consume the advertised food (Coon, Goldberg, Rogers, & Tucker, 2001). Family celebrations, socializing and relaxation situations have been shown to lead to relapses in dieting behaviour in overweight adults (Drapkin, Wing, & Shiffman, 1995; Grilo, Shiffman, & Wing, 1989). Individuals have the most difficulty coping when eating in larger group settings. As there are more family gatherings such as camping trips and barbeques in the summer, this is likely a difficult time for children. This higher availability of preferred foods and increase in food variety in the summer could lead to weight gain, as it is known that highly palatable foods are consumed in greater amounts (Roberts, 2000). In fact, it has been shown that in an adult weight control program, 73% of relapse crises are precipitated by food stimuli (Grilo et al., 1989). One food item that has been reported by patients to increase considerably during the warmer summer months is sugar-sweetened drinks and this consumption is correlated with adiposity (Gillis & Bar-Or, 2003). In another study by Ludwig, Peterson, and Gortmaker (2001), the authors followed 548 school children over a 2-year time span, and found that for each serving of sugar-sweetened drink consumed, body mass index and frequency of obesity increased. The reason for this may be related to the failure of the children to decrease their intake at subsequent meals. The drinks may have added to the calories consumed instead of displacing energy from solid forms (Mattes, 1996). States of under-arousal can lead to overeating. In adults, relapses in dieting occur while relaxing, waiting or when in between activities (Grilo et al., 1989). Without the daily schedule of school, children will have more idle time that could lead to overeating. Children at our centre often cite boredom as one of the main reasons for searching for food in the summer.
142
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A successful technique often used in weight control programs is self-monitoring, and adults who keep records have been shown to lose 64% more weight than those who do not self-monitor (Sperduto, Thompson, & O’Brien, 1986). Many of our patients failed to keep records of their activity and nutrition goals during the summer months compared with the school year. This could also explain some of the weight gain during the summer. The earliest reports of seasonal variations in weight and height in healthy children originated in the early 1900s. The rate of weight gain was greatest in the autumn (Attarzadeh, 1983). Since that time, the growth patterns of thousands of male and female children well nourished, supplemented and malnourished have been well documented and similar trends in seasonal growth rates have been found. This is true at all ages after the first year, including the adolescent pubertal period (Tanner, 1977). Thus this also underscores that the increase in weight in the summer vacation was likely due to changes in their eating or exercise patterns or both. In conclusion, for a weight control program in obese children and adolescents to be successful, strategies need to be developed to deal with the summer vacation period. The pattern of weight gain is different from that seen in adults. Families need to be aware that there are more stimuli present for children during the summer that lead to overeating. The environmental cues that cause an increase in eating and in sedentary time need to be recognized and overcome by the child and the whole family unit.
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