Many schools are scrambling to meet a 2006 government mandate for school-wide wellness policies, which includes offering healthy food options during lunchtime. But simply making healthy foods accessible doesn't mean that kids will embrace healthier choices.

Researchers at Loyola University and the University of Illinois at Chicago evaluated a "salad bar project" at two schools in Chicago to determine how to effectively encourage children to eat healthier foods. They found that when nutrition education, which included learning about how vegetables are grown and what they do for the body, and a chance to touch and taste the vegetables, was added to a salad bar option at lunch, the number of students selecting salad bar items quadrupled.

A recent study called The Strong Heart study (SHS) concluded that obesity causes heart enlargement and impaired heart pumping function in adolescence. The study included 460 American Indian teens, whose hearts were examined to measure size, shape and pumping function. Those who were overweight or obese had larger and heavier hearts, thought not to be totally related to changes in blood pressure that can occur with obesity. Those teens that were obese also had signs of abnormal pumping function.

While this study was confined to the American Indian population, other studies of different ethnic groups, including Caucasians and African Americans, have demonstrated similar results.

A recent study published in Hypertension: Journal of the American Heart Association concludes that teens with insulin resistance are likely to have heart problems later on in life.

Insulin resistance is a condition that increases your likelihood of developing diabetes. Our bodies use insulin, a hormone produced by the pancreas, to convert food into energy. Excess body fat makes the body resistant to the action of insulin, which causes the pancreas to produce even more insulin. Eventually the pancreas is unable to produce enough insulin to convert food to energy.

Insulin resistance plays a role in the development of cardiovascular disease, which damages the heart and blood vessels.

Researchers in the study followed a group of 244 Minneapolis-area teens over a six-year time period. They found that those with increased insulin resistance at age 13 had a corresponding increase in systolic blood pressure and triglycerides by age 19. High blood pressure and elevated triglycerides are two factors that increase the risk for cardiovascular problems such as heart attack or stroke.

How to keep this from happening? First, help your child to maintain a healthy body weight into and beyond early adolescence. Most importantly, encourage regular exercise. Exercise helps the body to use insulin efficiently—and to prevent or reduce insulin resistance.

Researchers from the Harvard School of Public Health have determined that those with a higher-than-normal body mass index (BMI) at 18 have as much as a three-fold risk for premature death as adults than those with a normal BMI. Examining the records of 102,400 women enrolled in the Nurses Health Study II, the researchers found that those women who had a higher-than-normal BMI at 18 years old, prior to the start of the study, were far more likely to have died at some point during the 12 years of the study than those of normal BMI.

Further studies are being conducted to determine whether taking diet pills such as sibutramine, along with nutrition counseling and careful medical monitoring, may be an effective way for obese teens to lose weight and lower the risk of premature death.

Have you ever seen an overweight bug? Insects are able to avoid overweight over generations by evolving metabolically to adjust to changes in their diets.

Entomologists with the Texas Agricultural Experiment Station along with other researchers recently conducted a series of studies to see how caterpillars would adapt over several generations to changes in their diet. They found that when the insects were fed diets rich in carbohydrates and low in protein, their bodies were able to eat the high carbohydrate diet without gaining excess weight. But when the diet was changed to one low in carbohydrates and high in protein, the caterpillars’ bodies adjusted by storing the carbohydrates as fat, enabling them to maintain weight.

Scientists suggest that the human nutritional environment has changed dramatically over the past century, from a diet higher in protein and low in carbohydrates to one high in carbohydrates, especially refined sugar - but we, unlike the caterpillars, are unable to change our metabolic processes and so we convert the excess carbohydrate to fat.

If you've ever experienced the "plateau" stage of a weight loss program, you understand how discouraging this can be. A plateau is a phase during a weight loss program where weight refuses to budge in spite of a negative energy balance - or more energy being expended through exercise than taken in via calories.

Researchers suggest that this common phenomenon is due to the way our bodies are programmed. The human body is well equipped to conserve energy during periods of famine; that is, if food is not plentiful, our bodies are able to maintain weight and energy by slowing the metabolism. This mechanism of food conservation worked for ancient civilizations, when people were hunter-gatherers and food was not always available.

But in today's environment of excess food consumption and inactivity, the human body is not equipped to speed up metabolism to work off the extra pounds.

While there is no perfect answer for moving past a plateau phase, experts recommend increasing the intensity or duration of exercise or adding different types of exercise to your current exercise program.