A weight problem is usually a matter of losing balance. Weight gain is the result of a simple equation: more calories being eaten than are burned off, through exercise or other physical activity. Children are eating more and moving less. They spend more time sitting still and watching life onscreen than participating in it.

In many cases, they're also following their parents' and peers' lead. When an afternoon with Mom and Dad regularly means sitting and watching a movie and sharing a bucket of buttered popcorn, and when going out with friends means spending the evening munching on fast food and playing video games, it becomes clear that there's a serious disconnect between what people place importance on and what their bodies require for good health.

Learning by Example

Teaching your child good manners, compassion, kindness, and social skills like sharing is probably an everyday priority in your home. It's something you spend as much time on as you do promoting good academic habits. Most parents model these behaviors as much as they can, particularly when a child is very young. But has it been a priority in your household to model regular physical activity and good nutrition?

Kids learn by example, whether it's a good one or a bad one. Even if your child is already a teen, you are his primary role model. When he sees his parents hit the couch after dinner and stay there until bedtime, he assumes that's the norm. Why not spend Saturday afternoon with a bag of chips and a video game and Sunday with donuts and the newspaper if that's the way Dad spends his weekend?

That's why you can't expect your child's fitness plan to be a solitary venture. Every member of the family — parents, siblings, and even the dog (if he'll acquiesce) — must educate themselves on healthy habits and work together towards nutrition and exercise goals. The good news is that it's never too late to get started. Chapter 4 has more information on getting your family with the program.

Cybersloth

Clearly, today's child spends a lot more time on sedentary pursuits like PlayStation and instant messaging than their parents did when they were children. Of all kids between the ages of two and seventeen, 92 percent play video games, and two out of three have some kind of home gaming system. Eighty-three percent of all American households with children have a home computer, and 78 percent of those are online. All told, kids spend an average of six and a half hours each day in front of a media screen of some sort (such as the television, movies, computer, or video game). Physical activity is at an all-time low among children and adolescents; over a third of high school students don't get any daily vigorous exercise — that is, exercise that causes perspiration, elevated heart rate, and hard breathing.

Teens are high-volume consumers of media, and because of their growing autonomy and disposable income, they represent a particularly attractive demographic for advertisers to target. Today's teen spends about forty-five minutes a day online (more if he's between the ages of fifteen and seventeen), plays video games for fifty-five minutes daily, and watches television for just over three hours per day. And the trend isn't limited just to “tweens” and teens. A Kaiser Family Foundation study found that a third of all children aged six and younger had their own televisions in their bedrooms, and 27 percent have a VCR or DVD player. On any given day, two-thirds of American children aged six or younger spend an average of two hours watching “screen” media (television, video games, movies, or computer).

There's nothing wrong with your child engaging in age-appropriate television and movie viewing, gaming, and online activities, as long as it's for a reasonable amount of time and she is still getting the physical activity she requires. The growing number of media options and greater access to them can make this a parental challenge, but the goal is an achievable one. Chapter 10 has information on how much exercise your child should be getting.

Genetics and Heredity

Overweight parents are statistically more likely to have overweight children, though whether that's due to nature, nurture, or (most likely) a combination of the two remains to be seen.

Your size and shape, along with that of your child's other parent, is hard-coded into his genetic blueprint. If you are shaped like an eggplant and your husband like a tomato, it's doubtful your child will turn out to be a celery stalk. While inheriting a certain body frame type may be inevitable, your child can influence how he pads it through proper nutrition and regular exercise.

Researchers have theorized that an inherited genetic trait known as the “thrifty genotype” may be responsible for the growing problem of obesity worldwide. Your ancestors may have had specific genetic programming that slowed their metabolism to store body fat when food was plentiful (hence the term “thrifty”). In times of famine, that stored fat became available and allowed them to survive. Today, that same genotype can cause weight to balloon in people living a Westernized lifestyle characterized by high calories and low physical exertion.

Medical Conditions

There are several genetic disorders that can impact body weight, though most of them are rare. These include Bardet-Biedl syndrome and Prader-Willi syndrome, a condition that affects the appetite-regulating function of the hypothalamus, resulting in uncontrolled eating. Endocrine disorders (that is, conditions characterized by hormonal imbalances) and autoimmune diseases that often have weight gain as a symptom include Cushing's disease, polycystic ovary syndrome (PCOS), hypothyroidism, and Hashimoto's thyroiditis.

This list is not all-inclusive. You should talk to your child's pediatrician if you suspect your child's weight may be related to a medical condition. A visit to a qualified health-care professional is an essential part of starting your child on a fitness program, regardless of the cause of her weight problem. Chapter 3 has more information on working with a health-care team.