The US and Canada not alone in the obesity epidemic – other Western countries such as the UK are also combating ever-rising rates of overweight and obesity, particularly among children. While non-Western countries including Japan and Singapore continue to have lower rates of obesity (about 10% of children are overweight/obese in Singapore vs. ~ 20% in Canada), the relative rate of obesity in younger generations have increased dramatically over the last several decades.
I was recently in Tokyo and was fortunate enough to attend the 6th International Sport Science Symposium on “Active Life” hosted by Waseda University, Graduate School of Sports Sciences. Here are a few summaries of excellent presentations from the conference that provide insights into the worldwide battle against obesity.
“Children’s Metabolism: Exercise and Breakfast Effects” – Dr. Keith Tolfrey, Loughborough University, UK.
Dr. Tolfrey presented some of his work investigating the effect of meal composition and exercise type/intensity on FatMax (maximal fat oxidation) and insulin sensitivity. In one study of adolescent girls, his team found that the metabolic response to high glycemic index (GI) breakfast was elevated in both groups (which was expected), YET overweight girls showed significantly higher peak insulin responses and greater blood glucose total-area-under-the-curves when compared to healthy weight girls (1). Blood glucose total-area-under-the-curve is a measure of how much blood sugar rises relative to baseline AND how long it stays elevated.
No Baloney’s takeaway message: Eat breakfast! Choose low GI carbs most often – multigrain bread, oatmeal, think lots of fibre. Including protein and healthy fat with breakfast will result in a lower total meal GI, and help you feel full longer. As Dr. Tolfrey’s work suggests, consuming a low GI breakfast may be even more important for those that are overweight or obese. For more of Dr. Tolfrey’s work, click here.
“Childhood Obesity and Physical Activity: A Singapore Perspective” – Dr. Stephen Burns, Nanyang Technological University, Singapore.
Singapore is one of those rare success stories – pediatric obesity rates actually declined between 1992 and 2010. Much of Singapore’s success has been attributed to the Trim and Fit (TAF) Program: introduced in 1992, the program targeted nutrition and physical activity in schools through various means – additional exercise for overweight children, restricted food choices and parent education. Over this 15 year time span, pediatric obesity rates dropped from 14% to 9.8%. Concerns about emotional and body image impact of such programs were raised in the media in 2005. These concerns are in line with recent findings from the US where school-based obesity programs have been implicated in the rise in eating disorders. The TAF program was replaced in 2007 with a Holistic Health Framework, which focuses on improving nutrition and physical activity of ALL schoolchildren, seeking to promote healthy lifestyles and not just weight loss.
Dr. Burns argued that some of the success may have been overstated, as the TAF program coincided with a change in weight-for-height assessment methodology, which may have artificially overestimated success, and low physical activity levels are still a problem for children in Singapore. Despite these potential drawbacks, over the past 5 years Singapore’s rate of pediatric obesity has been stable, which is a success in and of itself.
No Baloney’s takeaway message: Singapore is a unique situation – large population, small total area and lots of government involvement makes instituting and monitoring programs a lot easier than in Canada. We think that school-based programs should focus on targeting ALL children rather than stigmatizing those that are overweight, to avoid the development of food and weight preoccupation. In terms of targeting those most at risk, family-based interventions where change at home is encouraged have shown some promise (2). Of course, buy in from parents is absolutely necessary as is education surrounding both improved nutrition as well as increased physical activity.
“The Role of Exercise and Nutrition in Lifestyle-Related Diseases” – Professor Toshio Moritani, Kyoto University.
Based on current data, the estimated energy intake in Japan has not changed dramatically in several decades – from a peak of 2,226 kcal per day in 1972 to 1,902 kcal per day in 2004, which is similar to post World War II intakes. Professor Moritani argues that based on these nutrition data, overeating is not to blame for burgeoning rates of obesity in Japan, but rather the “energy surplus” derived from lack of physical activity.
He then discussed a prevailing hypothesis that obesity is inter-related with nervous system dysfunction in both children and adults, specifically the autonomic nervous system (which we discussed in a previous post) (3). Essentially, nervous system dysfunction (of which heart rate variability is a common measure), results in decreased metabolic function and NEAT – Non-Exercise Activity Thermogenesis (4) – the calories you expend outside of exercise, that is during work and leisure time. NEAT has enormous intra- and inter-personal variability, as much as 1500 kcal per day! What impacts NEAT? Overfeeding (i.e., overeating) actually decreases NEAT, whereas exercise training increases NEAT (5). Higher NEAT, higher baseline energy expenditure and less likelihood of “energy surplus” contributing to weight gain. As Dr. Moritani points out, “dieting” via caloric restriction WITHOUT accompanying physical activity does nothing to change NEAT; long term gains and physiologic change occurs with physical activity only.
No Baloney’s takeaway message: Professor Moritani’s presentation was reminiscent of the 2011 Canadian Obesity Network Forks vs. Feet debate with Drs. Yoni Freedhoff and Robert Ross – is overeating or sedentary lifestyle contributing MORE to the obesity epidemic? At No Baloney, we figure why fight – it’s both!
In the Canadian context, our obesity epidemic is multifactorial – neither lack of activity nor energy intake are solely to blame. Interestingly, there is some debate as to whether caloric intake has been increasing in Canada. Data from 2002 suggest yes: intakes increased from 2,358 kcal per day in 1976, to 2,788 kcal per day in 2002. More recent findings from the Canadian Community Health Survey 2004, however, suggest no: caloric intake has been fairly stable over the last three decades. But we all know how accurate self-reported energy intake is! Indisputably, we have become less active and more inactive (6) – creating the perfect storm for lasting weight gain.
We agree with Dr. Moritani that getting away from traditional “dieting”, where caloric restriction is all that’s needed, is necessary for maintainable weight loss. It’s about eating less and moving more… but it doesn’t have to be intense. Dr. Moritani’s group (7) showed that six minutes of stair climbing-descending 90 minutes after a meal was enough to significantly reduce post-prandial blood glucose levels in a small (n = 8) group of middle-aged men with impaired glucose tolerance – how easy is that to incorporate into client recommendations! When it comes to activity, don’t forget the importance of NEAT: be a “breaker” not a “prolonger”. Divide your day up with mini-movement breaks rather than sitting on your butt for 8 hours straight. Fidgeting is okay too!
- Zakrzewski JK, Stevenson EJ, Tolfrey K. Effect of breakfast glycemic index on metabolic responses during rest and exercise in overweight and non-overweight adolescent girls. Eur J Clin Nutr 2011 [epub ahead of print]
- Teder M, Mörelius E, Bolme P, Nordwall M, Ekberg J, Timpka T. Family-based behavioural intervention programme for obese children: a feasibility study. BMJ Open 2012;2.
- Nagai N, Matsumoto T, Kita H, Moritani T. Autonomic nervous system activity and the state of development of obesity in Japanese school children. Obesity Res 2003; 11:25 – 32.
- Levine JA, Vander Weg, MW, Hill JO, Klesges RC. Non-exercise activity thermogenesis: the crouching tiger hidden dragon of societal weight gain. Arterioscler Thromb Vasc Biol 2006; 26: 729 – 36.
- Amano M, Kanda T, Ue H, Moritani T. Exercise training and autonomic nervous system activity in obese individuals. Med Sci Sport Exerc 2001; 33:1287 – 91.
- Thyfault JP, Booth FW. Lack of regular physical activity or too much inactivity. Curr Opin Clin Nutr Metab Care 2011; 14:374 – 8.
- Takaishi T, Imaeda K, Tanaka T, Moritani T, Hayashi T. A short bout of stair climbing-descending exercise attenuates postprandial hyperglycemia in middle-aged males with impaired glucose tolerance. Appl Physiol Nutr Metab 2012; 37:193-6.