Obesity, overweight, and awareness

Do parents notice if their child is overweight or obese? Recent research in Germany and the United Kingdom suggests they often do not, and that making sure parents are aware of a child’s overweight status is an important first step in helping the child grow up healthy.

In research published in October in Cardiology of the Young, German researchers led by Dr. Christine Graf found their whole-family intervention, designed to help parents guide a child to a healthy weight and lifestyle, was quite effective, compared to no intervention at all. Children in treatment ended the 9-month experiment with their Body Mass Index (BMI) closer to normal, and lower blood pressure during the heart’s pumping, or systolic, phase. Dr. Graf’s team from Cologne also found that children who were screened and identified as overweight during the initial phase of the study, but who received no organized intervention, also decreased their systolic blood pressure and became less overweight over the study period, compared to a control group. Obese children and those who were not told anything about their weight status did not achieve these beneficial changes.

The German intervention, called StEP TWO, combines nutritional education and an active lifestyle program for parents and children, with additional physical co-ordination training for children.

Obesity in children matters

“Obesity in children is rising faster than in adults, and has become a major public health problem,” says Dr. Brian McCrindle, a staff cardiologist and section head of preventive cardiology at The Hospital for Sick Children in Toronto. So researchers around the developed world are trying to find programs that really influence how families eat and enjoy physical activities.

Dr. Graf’s team found that telling parents that their child is overweight might be helpful even in the absence of a medical intervention. An explanation for this may lie in the findings of Plymouth, UK-based team led by Alison Jeffery, a research nurse at the Peninsula Medical School of Exeter and Plymouth Universities. Ms. Jeffery, describing her study of nearly 300 families in the British Medical Journal, said many parents of overweight and even obese children did not recognize their condition. Her conclusion was that many parents were unconcerned about this condition because they were unaware, in denial, or simply didn’t have enough experience with healthy children to recognize obesity when they saw it.

“It looks like the health messages are falling on deaf ears. We'll be pouring money down the drain on this [issue] unless parents become more aware of what constitutes a healthy weight,” Ms. Jeffrey told a Diabetes UK medical conference in 2004. Concern that parents may be unaware of their child’s weight problem has caused some school authorities to add a child’s BMI to report cards. Controversially, the US state of Arkansas sends every family a report classifying their child as normal, at risk, or overweight.

Obesity screening: Measuring healthy weight with BMI and growth charts

BMI, or body mass index, measures a person’s weight in proportion to their height, and is widely used to identify a healthy weight range for adults. It assumes that all extra weight is fat, which may not be true for those with a larger muscle mass. For children, doctors often use a BMI-for-age growth chart. This statistical tool allows your physician to say that, for instance, your child is at the 70th percentile, that is, heavier than 70% of children the same height, age and sex. The term overweight is used for children at the 85th to 95th percentile for weight, while obesity refers to those at or above the 95th percentile. This is not a medical diagnosis, but instead a screening test, suggesting a more complete evaluation of children the screen identifies.

What can be done?

Children who are overweight or obese can benefit from lifestyle changes that help them burn more energy in daily activities and consume nutritious food that is less dense with calories. Recommendations from Dr. Gilles Plourde, of the Laval University Department of social and preventative medicine, published in Canadian Family Physician this year, echo the German study’s involvement with the whole family.

On nutrition:

• Many children who are overweight or obese eat too many calories, yet not enough key vitamins and minerals. Dietary changes need to improve a child’s nutrition, not just reduce portion size.
• Avoid rapid weight loss; the aim is to slowly lower the child’s BMI, while allowing for normal growth. In most cases, children should not “diet” in the usual sense, because a treatment goal is to establish lifelong healthy eating habits. Dieting is a powerful trigger for several eating disorders, which are common and sometimes life-threatening conditions.
• Change one thing at a time. You can’t hope to eliminate soft drinks, switch to low-fat milk products, reduce fast food consumption, and reduce portion size all at once.
• Food should not be used as a reward.

On physical activity:

• Increasing physical activity is good, especially if the whole family is involved.
• Physical activity can be increased in steps, up to 30 or more minutes of moderate intensity exercise most days.
• Separately from increased exercise, children should be guided to reduce their low-energy activities, such as TV, computer use, and video games.

“Clearly, preventing your child from becoming overweight should be part of good parenting. Once your child is overweight, it can be a very difficult and a long challenge to prevent them from becoming an overweight adult,” Dr. McCrindle says.

If you are worried that your child may be overweight, talk to your child’s physician. To evaluate weight, doctors take into account your child's individual history of growth, your family's weight-for-height history, and where your child is on the growth and BMI charts. Although some children may grow out of an overweight state, studies show this often does not occur. Also, there are benefits to catching a weight problem as early as possible. Lifestyle changes can bring more physical activity and better nutrition to the whole family, reducing everyone’s risk of diabetes, heart disease, and other consequences of obesity.

Resources:

An interactive BMI-for-age growth chart for children from two to 20 years of age:
http://apps.nccd.cdc.gov/dnpabmi/Calculator.aspx?CalculatorType=Metric