I thank the committee for its invitation to attend. I have two messages in my presentation and will use slides to keep all the members awake. One concerns the importance of primary prevention; the second is the under-utilised role of physical activity, particularly in our children.
I will start with a quote from Dr. Philip James, who was the chairperson of the British international obesity task force. He said:
We are not dealing with a scientific or medical problem. We are dealing with an enormous economic problem that is already accepted is going to overwhelm every medical system in the world.
We are all aware of the high levels of obesity and overweight among Irish children. In DCU we have undertaken a number of studies, one of which involved 5,000 Irish 15 to 17 year olds. We showed that 15% of them were overweight and 5% were obese. We saw pretty much the same proportions in both boys and girls.
The point about obesity is that it is an insidious disease, as has been noted. It does not occur overnight. An example from the United States, using data from 2006, shows the percentage of the population in each state that was clinically obese. The winner in 2006 was the state of Mississippi, where approximately 30% of the population was clinically obese. The people in Mississippi did not wake up one morning in 2006, look in the mirror and figure out they were obese; it happened over a long period. The blue area shows the states in 1992 where 15% to 19% of adults are obese and the green area shows states where 10% to 14% of adults are obese. As we move from 1992 to 1997, we see states with levels of obesity higher than 20%. As we move onto 2001, we can see that people in Mississippi were not very happy as they have obesity rates greater than 25%. From 2003 to 2006, more than 30% of the population of some states are clinically obese. The trend continues every year up to 2009. Even with billions of dollars spent, the population of America is becoming obese.
They started to collect the same information on children aged ten to 17 years. The next chart shows the number of overweight children from 2003 to 2007. By 2007, over 30% were obese, with an increase of 18% in the number of female children who were overweight and an increase of 10% overall. The trend is the same in the measure of obesity. As Professor O'Shea alluded to, once the child becomes obese, he or she has an 80% likelihood of remaining obese for the rest of his or her life. The issue is to arrest that and stop it from happening in the first place.
Two environmental factors cause obesity, what one eats and what one burns. The factors that determine this are the basal metabolic rate, the resting rate, and the other key determinant of our energy expenditure, our physical activity. When these two are in balance, our weight remains stable. If we eat more than we consume, we go into a positive energy balance and weight increases. We all go on a diet when that happens. The good news is that every diet works; the bad news is that every diet works only in the short term. Dieting asks people to change their behaviour, which is the hardest thing to do. The easiest thing to do is to adopt a behaviour in the first place. The solution should be primary prevention. Unfortunately, we are starting to use other interventions for children who are morbidly obese, including pharmacological therapy and surgical intervention. It is pretty sad to have prepubescent kids undergoing stomach reduction surgery at that age. We do not know the long-term issues for the rest of their lives.
The other side of the equation is energy expenditure, which is very important. If one burns more calories than one takes in, body weight will reduce. Ideally, we like to maintain an equilibrium. The current model is that our obesity problem is due to the fact that children are eating more calories than they expend. That is the prevalent view but it looks only at one side of the equation. The presumption is that the child has not increased caloric intake in 30 years but because our physical activity levels have decreased, the small decrease results in an increased caloric intake relative to expenditure. Even if kids eat what they were eating 30 years ago, our body weight will increase because we are exercising less. We spent too much time on caloric intake and not enough on energy expenditure. I have provided pictures of nine DCU athletes. Three of them have already qualified for the Olympics and the other six are looking to qualify. Each of them consumes twice the number of calories compared to the average male or female of the same age. I do not see much fat or body weight on the athletes because they expend what they eat through physical activity. The take-home message is that we are underestimating this aspect from the health perspective as well as the obesity perspective.
Many years ago, we were hunters and gatherers and our genes have evolved to support a physically active lifestyle. Our genes have not changed in the past 10,000 years and if we do not get regular exercise on a daily basis, our genes maladapt and we get hyperkinetic diseases, which are due to inactivity or lifestyle. Such diseases, such as diabetes, cardiovascular disease, site-specific cancers, frailty and osteoporosis, are the main causes of expenditure in our health care budget.
I have also provided the committee with pictures of our children 30 years ago. The prevalence of technological innovation means we are engineering activity out of our lives. The vast majority of children lead sedentary lifestyles. Even if they eat what they were eating 30 years ago, their body weight is increasing and the balance is in disequilibrium because they are so inactive. Sedentary behaviour is known to be an independent risk factor for at least 35 health conditions. A new term is emerging, sedentary death syndrome, which describes the sedentary lifestyle mediated diseases resulting in premature morbidity. These all have their genesis during childhood and adolescence. There should be primary prevention during those stages.
It is recommended that Irish teenage boys and girls should get 60 minutes of moderate to vigorous intensity activity every day. A study of 5,000 teenagers shows that 65% of Irish teenagers do not meet those recommendations. This breaks down into seven out of ten Irish girls and almost six out of ten Irish boys. Another study assessed the fitness of Irish boys and girls using a bleep test, where the more runs one can do, the fitter one is. The normal weight boys could do 77 runs but the obese boys could only do 42. The best predictor of health and how long one will live is aerobic fitness. One rarely sees people who are aerobically trained going to a primary care physician with multiple risk factors for disease. However, the worrying trend for me is among girls. Normal weight girls had the same fitness level as the obese boys. If one is not physically fit, how can one perform physical activity and burn calories? It is an important aspect of the problem.
It is also recommended that prepubescent kids, prior to secondary school, should accumulate approximately 15,000 steps per day. A study by Dr. Catherine Woods on fifth and sixth class primary schoolchildren shows that 11% of kids meet the recommendations during the week and 9% at the weekend. It is alarming and the trend is occurring at a younger and younger age.
Another study showed that, on average, six out of ten Irish secondary school children commute to school in an inactive fashion, either by car, train or another mode of transport. Only four out of ten actively commute and the figure is higher for girls than boys. Another published paper shows that if a child lives more than 2 km from the school, he or she will not actively commute to school. For every kilometre beyond 2 km, the likelihood increases that they will not actively commute to school. This is a major transportation issue.
It is extremely important that our kids are physically active and that we reduce obesity. I have displayed a chart showing the coronary arteries. In the wall of the arteries, plaque begins to accumulate. The earlier the child is exposed to risk factors, such as obesity, inactivity, smoking and high levels of glucose, the earlier this plaque begins to occur. Over a lifetime, the plaque ruptures and we get a clot, which causes the majority of heart attacks. This occurs through plaque that began to develop not in the 20s and 30s but in prepubescent kids. This is due to lifestyle. The bad news is that four out of ten women and six out of ten men will have a heart attack or sudden death as their initial presentation and they have heart disease due to ruptured plaque. The etiology of these diseases is that they begin early in life.
Plaque in the arteries of more than 0.5 mm is significant. A recent study published in the United States reported on autopsies carried out on children who died in motor vehicle accidents. The study used ultrasound to look at the children's arteries and, amazingly, two out of ten 13 to 18-year-olds had a significant build-up of plaque in the coronary arteries. I do not know if this group were obese kids but my calculation was that they were inactive and overweight kids.
We can measure a biomarker in our blood called C-reactive protein and it predicts the risk for cardiovascular disease. Under normal circumstances, it should be less than level 1. Levels 1 to 3 have an increased risk and those above level 3 have an increased risk of cardiovascular disease. A study of a population of Irish teenagers showed that an obese teenager has a level of 3.8. If I produced an ultrasound image, it would show a significant lesion in one of their coronary arteries. These are Irish kids, not American kids. The normal weight kids are perfect but the overweight kids are at risk and the obese kids have very high levels of C - reactive protein, which is a marker of inflammation and atherosclerosis. When we group them by fitness level, we see the same trend. The kids who were highly fit or moderately active were in the normal range, less than 1, while the kids who were untrained or sedentary were at 3.3.
Physical activity is extremely important for our children and not just in the context of obesity. Every effort should be made to develop appropriate levels of fitness in our schools. Ireland should become the model for the rest of the world in this regard. I was involved in a small project with RTE recently in which 10,000 kids took part in order to discover which first-year class could improve the most over a six-week period. The changes that took place in six weeks were phenomenal. I got letters from parents thanking me for getting children, particularly young girls, involved. These children were not involved in sport normally, but because we were giving the prize to the school that improved the most, their result was just as important as that of the fittest in the class.
In addition to activity being important in the context of obesity, it improves mental health, reduces rule-breaking behaviour, improves attention span and classroom behaviour, has a positive impact on academic performance and can play a significant role in the enrichment of the child's social life, development and social interaction.
