The key to maintaining normal body weight lies in regular exercise and getting weight under control before puberty.

Even though some teenagers may eat less than their thinner peers, fat cells laid down in the body at an early age never go away.

Lack of exercise and an abundance of fat cells alter body chemistry and create an environment where fewer calories in cause more weight gain.

And obesity expert Matthew Gillman of the Harvard School of Public Health says the amount of physical activity kids participate in is key. “When you’re less physically active, you actually need fewer calories to maintain your weight,” he explains.

But if that weight is already higher than it should be, that could signal the beginning of a long-term problem.

“Once you become overweight, there are changes in your body that make you different from someone who’s not [overweight],” explains Sophia Yen of Stanford School of Medicine. “You have extra fat cells, and you have different insulin levels,” which can make it feel like you’re eating less than you are.

Being fit at at early age is crucial and tackling weight gain before it begins can provide a lifetime of good health.

Going back to school can be stressful for parents and kids.

But there is often more than just nerves to deal with when heading back to classrooms where kids touch and share everything.

Picking up bugs along the way is often a simple fact of life.

Exposing kids to chemicals is not always the best way to deal with infections and infestations, however.

For problems like pink eye, lice and anxiety there are natural remedies that can ease the pain of infection without the side effects of medications.

Should your child’s annual physical include a cholesterol screening?

And, if so, should the results warrant, should he be put on statins?

This is the debate amount physicians.

There is worry that pharmaceutical companies may have too much sway over doctors who may be influenced by money to push cholesterol lowering drugs on children.

However, a growing obesity rate would suggest that high cholesterol and the danger of developing heart disease is a real possibility.

The guidelines are endorsed by the Academy of Pediatrics, which publishes the journal that carried the critical commentary Monday. The panel recommends that all U.S. children should get blood tests for high cholesterol as early as age 9 and that testing should begin much earlier for kids at risk of future heart disease, including those with diabetes or a family history of heart problems. Treatment should generally begin with lifestyle changes including diet and exercise, the guidelines say.

Cholesterol drugs would be recommended for some kids, but probably less than 1 percent of those tested. But the advice says those drugs, including statins, shouldn’t be used at all in children younger than 10 unless they have severe problems.

The guidelines aim to help prevent and treat conditions in children that put them at risk for later heart-related problems. At least 10 percent of U.S. children have unhealthy cholesterol levels and one-third are overweight or obese.

How about preventing obesity and not taking the risk of side effects from unnecessary drugs?

The debate centers around school lunch and the longtime promotion that milk builds strong bones.

Dr. Neal Barnard, president of the PCRM, (Physicians Committee for Responsible Medicine) has stated that, “Research has now made it abundantly clear that milk doesn’t build strong bones. Whether we are talking about children who are forming bones or older people who are trying to keep their bone integrity, milk doesn’t have a beneficial effect on either one.”

The promotion of milk to help build strong bones in kids is, “in effect, the promotion of an ineffective placebo,” writes the Physicians Committee for Responsible Medicine (PCRM) in its petition [PDF]. “Milk is high in sugar, high in fat and high in animal protein” — all of which counters its purported benefits to bone health, the committee argues.

The PCRM notes that dairy products, including milk, are the No. 1 source of saturated fat in Americans’ diets. Drinking milk for the calcium it contains is therefore a losing strategy, especially since people can get their daily recommended calcium from other, more nutritious foods. And for millions of Americans who are allergic to milk — including 1.3 million children — or intolerant to the lactose it contains, drinking milk carries potentially severe health risks.

The FDA has finally publicly recognized the dangers of BPA in plastics and the environment.

The ban is based on concerns voiced by the American Chemistry Council which encouraged the FDA to phase out use of BPA in these particular products.

This was designed in part to counter years of negative publicity from consumer groups.

The dangers of BPA in the environment and their effect on all humans have raised red flags for years.

Previous research in animals has associated BPA exposure to disruptions in reproductive and nervous-system development in babies, but the FDA has long maintained that such findings cannot be applied to humans. Other observational studies in humans have associated prenatal exposure to the chemical with behavior problems and childhood asthma. Just this week, the journal Pediatrics published a study linking BPA in dental fillings to problems like depression and anxiety in kids.

Some 96% of pregnant women have measurable levels of BPA, according to a 2011 study by University of California, San Francisco, researchers; in fact, data show that nearly every American has traces of BPA in their urine from exposure to food and beverage packaging.

For now, the federal government maintains that BPA does not harm humans, but it is spending $30 million on its own studies to assess the chemical’s health effects on humans.

A recent study found that kids who played on three or more sports teams in a year, were 27% less likely to be overweight, and 39% less likely to be obese than those teens who did not play team sports.

The study also found that biking or walking to school had less of an effect on a student’s weight – although it did reduce their likelihood of being obese.

Researchers believe playing high school sports, which usually involve regular practices and competitions, reduces a child’s chances of having a weight problem because of the strenuous and consistent workouts. Therefore, study authors conclude, increasing a child’s opportunity to play sports, even if they are not gifted athletes, should be a priority, especially for teens and children entering middle school or high school.

Organized sports is a fun way to motivate kids to keep active and stay competitive.

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Owning a pet can help boost your child’s immune system.

The belief is that pets bring germs inside the home allowing children to build up resistance to things with which they might not otherwise come into contact.

What may seem like a harmless pastime has proven to be psychologically destructive to a whole generation of boys.

“Arousal addictions” are just as powerful as addictions to cigarettes, alcohol, food and heroin and they are getting in the way of school work, relationships and ambitions.

The consequences could be dramatic: The excessive use of video games and online porn in pursuit of the next thing is creating a generation of risk-averse guys who are unable (and unwilling) to navigate the complexities and risks inherent to real-life relationships, school and employment.

Boys seem to be particularly susceptible and are falling behind in school, college admissions, graduations and in the job market.

“Failure to launch” has become a real thing not just a movie.

“Boys Adrift” by Dr. Leonard Sax talks about an epidemic of unmotivated drifters.

The Center for Disease Control reports that the leading cause of death for toddlers is drowning.

Summer is the time to relax and enjoy the sun but pool safety should never be overlooked.

Water survival skills, knowing CPR, fences around pools and life jackets and floating devices are no substitute for adult supervision of little ones.

Death rates were highest for children between ages 1 and 4. In this age group, about 2.5 deaths occurred for every 100,000 children in the population, the report said. Overall, there were 1.3 deaths per 100,000 people in the United States. More than half of all people treated in emergency rooms for near drowning were less than 4 years old, the report said.

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Everyday items such as car keys, remote controls, watches, flashlights and remote controls are within easy reach for curious little fingers.

Prying these items apart, retrieving and swallowing button batteries is often quite easy for children.