For the most part, Canadian children today live lives of unimagined privilege and good health – certainly compared with those in Shakespeare’s era, and likewise with kids now living in less advantaged parts of the world. They are taller, healthier and smarter than any other Canadian children in history. But when it comes to health, a downside to this privileged childhood existence seems to be emerging.
Obesity levels at all-time high
New research culled from several national surveys shows that Canadian kids have been getting progressively heavier since 1981. Twenty years ago, 15 per cent were considered overweight; by 1996 that number had jumped to 29 per cent of boys and 24 per cent of girls. “While children have become less physically active, they are taking in more and more calories. It’s a recipe for obesity,” says Dr. Khosrow Adeli, a professor in the department of laboratory medicine and pathobiology and head of clinical biochemistry at the Hospital for Sick Children in Toronto.
According to Nielsen Media Research, last year Canadian kids aged two to 17 watched about 15 hours of TV each week. Sitting in front of the TV or computer screen requires almost no expenditure of energy, except when kids walk to the kitchen for a snack. “They’re not just taking in more calories, they’re taking in more calories from fat,” says Adeli.
One alarming consequence of childhood obesity is that doctors now see health problems in schoolchildren that typically didn’t appear until middle age; for example, Type 2 diabetes, hypertension (high blood pressure) and hyperlipidemia (unhealthy levels of cholesterol and other fats in the blood). And overweight children are more likely to be overweight adults and to experience obesity-related problems such as heart disease, diabetes and certain cancers.
The asthma paradox
Another worrisome trend is the rising rate of childhood asthma. Surveys show that between 10 and 15 per cent of school-aged children are affected to some degree by this chronic lung disorder, which involves inflammation of the airways and in turn leads to shortness of breath, wheezing, coughing and chest tightness. The exact cause of asthma isn’t known, but common triggers include animal dander, cigarette smoke, dust mites, pollen, mould spores, exposure to cold air and exercise.
Children suffer more commonly from asthma than adults, mainly because their airways are narrower, explains Dr. Kenneth Chapman, director of the Asthma & Airway Centre at Toronto Western Hospital and University Health Network, and a professor of medicine at U of T. There has been a dramatic rise in asthma in kids under age 14; in just 18 years the rate has increased from 2.5 to 11.2 per cent.
Why the sudden increase? “The layperson assumes that it’s because of pollution,” says Dr. Chapman, “but environmental pollution is less a culprit than we think.” Instead, the real source of the problem lies closer to home: “Children today spend a lot of time indoors instead of playing outside. They also live in better insulated homes, and this has increased their exposure to respiratory irritants such as dust mites, pet dander and secondhand smoke,” he says.
Another problem may be that modern children – who tend to live in isolated, relatively clean environments – aren’t giving their immune systems a regular workout, says Dr. Chapman. “Because their bodies’ defence systems are no longer attending to outside infections, they preoccupy themselves with things that really aren’t hazardous to the body, like cat dander.” This may explain recent research showing that eldest or only children are particularly susceptible to asthma. The theory is that younger kids with older siblings, and those who attend day care at an early age, are exposed to many more germs, which allows their immune responses to develop more vigorously and may decrease their risk for asthma.
If your child has asthma, says Dr. Chapman, you should take the necessary steps to obtain proper treatment, and reduce household triggers such as dust and mould. “Finally, relax,” he adds. “Children often enjoy an improvement in their asthma because, as their bodies grow, their airways become larger. In fact, in about two-thirds of kids, asthma is much improved by adolescence.”
The ADHD explosion
While measles, mumps and chickenpox have largely vanished from childhood, a troubling new disorder has emerged: attention-deficit/hyperactivity disorder, or ADHD, which is believed to affect four to five per cent of school-aged boys and three per cent of school-aged girls. The main symptoms are inattention, hyperactivity and impulsivity, explains Dr. Wendy Roberts, an associate professor of paediatrics and medical director of the Child Development Centre at the Hospital for Sick Children. “The typical picture [of ADHD] is a child who is easily frustrated, can’t pay attention, daydreams too much, is impulsive or disorganized,” she says.
For an ADHD diagnosis, symptoms must have been evident before the child reached age seven, and the problems must have persisted for at least six months in two or more settings; for example, at home and in school. About one-third of children with the disorder also have some other psychological or developmental problem, such as a language or learning disability, says Dr. Roberts.
The common treatment for ADHD is behaviour therapy combined with stimulant drugs such as Ritalin (methylphenidate) or Dexedrine (dextroamphetamine), says Dr. Roberts. These drugs help focus attention and reduce hyperactivity in about 70 to 80 per cent of cases. Studies show that in Canada the number of prescriptions for such drugs has been rising steadily in recent years.
Some child experts and educators wonder if the condition is being overdiagnosed: “It used to be that when you had a kid who was difficult to handle, teachers would say he was challenging,” says Dr. Judith Wiener, a psychologist in the department of human development and applied psychology at the Ontario Institute for Studies in Education (OISE). “Now they call it ADHD and send the parents to the doctor. There are many children labelled ADHD who do not meet the clinical criteria.”
Kids with ADHD seem to benefit from highly structured schedules that include skill-building activities such as art, music, drama, and sports. It’s best to limit their TV or “any electronic hookup” time to one hour a day, advises Dr. Roberts.
Getting kids up off the couch
Here’s something to consider: only two out of every five children aged five to 17 are active enough for optimal growth and development, according to a 1998 survey by the Canadian Fitness and Lifestyle Research Institute in Ottawa. “We know that to maintain health, people need 30 to 60 minutes of moderate to vigorous exercise most days of the week,” says Dr. Roy Shephard, professor emeritus of applied physiology in U of T’s Faculty of Physical Education and Health.
In previous generations, regular participation in gym class and school sports was mandatory. More recently, physical education classes have been cut to a minimum. But people are starting to realize the folly of this approach: according to a recent national poll by the Globe and Mail and CTV, 96 per cent of those surveyed agreed that physical fitness courses should be “an integral part of the curriculum for primary and secondary school students.”
Some research suggests that kids who are more physically active do better academically. One ongoing study, started 25 years ago, has been following children at two elementary schools in Quebec who receive an extra five hours per week of physical education. Not only do these children perform better academically than kids at other local schools who get the standard amount of phys. ed., but they also seem to live healthier lifestyles later on. For example, as adults they are less likely to be smokers.
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