A nationwide survey conducted by the CDC has shown a 5.6% growth in obesity, and and 8% growth in diabetes, in a single year from 2001-02. Since 1991, the prevalence of obesity has increased over 74%, and diabetes has increased 61%.

Adult obesity-rates now exceed 25% in 31 states - up from 28 states last year and 19 the year before that. Adult obesity-rates now exceed 20% in 49 states and the District of Columbia. In 1991, no state had an obesity rate above 20%.

Over the past 30 years, the prevalence of overweight children has tripled. One in three American children is overweight or obese.

Reduction of fat and sugar intake in children is difficult due to several factors. Children's preference for high-sugar and high-fat foods determines their overweight tendency. There is much evidence that preferences for sweet taste are innate, and fat is frequently regarded as a source of "hidden" calories due to consumers' inability to determine the fat content of common foods.

Children's food preference begin forming from the moment they first eat. Infants who are breast-fed experience variety in the flavors of their mother's milk based on her diet. This variability in flavor facilitates the acceptance of solid foods once the baby weans. Formula-fed-infants experience only a single flavor, and tend to reject foods that are contrary to their innate preference for sweet and salty tastes.

Children's food preferences are strongly associated with food available in the home and their parents' eating habits. However, long-term parental restriction of palatable (sweet & high fat) foods tends to increase children's desire for such foods, and is negatively associated with their ability to self-regulate energy intake.

A significant factor in the explosion of obesity is the dramatic increase in portion size. In 1916, Coca Cola was sold in 6.5 oz bottles. In the 1950s, a 10 oz and 12 oz "king-sized" Coke was available, but the 6.5 oz size still accounted for 80% of sales. Today, a "small" soft drink is 24 oz, with "super size" drinks available up to half a gallon.

Since the 1950s, several type of foods have doubled and even tripled in portion-size:

• Bagels and Muffins have gone from 2-3 oz to 4-7 oz
• Candy Bars are now sold in 3.7 oz from a previous 1 oz
• Corn & Potato Chips are now often sold in 5oz individual portion bags

McDonalds offers sandwiches such as the Big Mac (216 g, 570 kcal; fat, 32 g), Big Xtra with Cheese (307 g, 810 kcals; fat, 55 g), and super-size french fries (198 g, 610 kcals; fat, 29 g).

Another important factor in the rise of obesity is the dominance of the fast-food industry. Fast-food retailers have been resilient through the economic crisis, while the majority of restaurants are struggling to survive.

The World Health Organization (WHO) and the Food and Agriculture Organization of the United Nations concluded that marketing of energy-dense foods by fast-food outlets is a "probable" cause of increasing overweight and obesity throughout the world.

The food and beverage industries spend over $10 billion per year (in the US.) marketing fast-food to children, compared to just $105 million spent on advertising fruits and vegetables.

Such advertising has a tremendous impact on youth; children as young as 2-6 years can recognize familiar brand names, packaging, logos and characters, and associate them with their products. In an identical food-tasting test, children reported that foods in McDonald's packaging tasted better, sometimes with a preference of over 77% over the generic unbranded product.

School food-policies have not helped the situation with obesity. Although schools provide federal school-meal programs which are nutritionally regulated, almost all schools provide competitive foods to their students. Competitive foods are those foods sold in schools, during the school-day, that are not part of the federal school-meal programs (they compete with them).

A 2005 report by the US Government Accountability Office (GAO) found that 9 out of every 10 public schools in the United States offered competitive foods to their students, and almost 30% of public high schools earned more than $125,000 from competitive food sales.

Proceeds from competitive food sales are often used to pay for special activities or items not covered by the school’s budget. As a result, there have been a number of challenges when local schools or parent-teacher-associations have sought to make sure only healthy foods are sold in schools.

Health and fitness education in schools has been implemented across many schools, but there is currently no evidence that the school environment interventions improved health behaviors outside of school.

A 1990 law passed by Congress limits commercials during children's programming to 10.5 minutes per hour on weekends and no more than 12 minutes per hour on weekdays.

However, a 2001 study found that it takes only 1 or 2 exposures to a 10- to 30-second food commercial to influence 2- to 6-year-olds' short-term preferences for specific food products. Even worse, young children, in contrast to older children, do not alter attention levels between commercials and programs. This plays an important role in children's development of food preferences and intake, since children influence 78% of fast-food purchase decisions and 17% of overall family spending.

The influence of mass media on children is even greater due to the widespread phenomenon of deceptive advertising. An extensive study of diet supplement and fitness advertising showed that nearly 40% of the TV, 54% of the newspapers and 74% of the tabloid ads make at least one representation that is certainly false.

Many of such ads showed before and after pictures in which the only discernible difference is in posture, and would sometimes take a subject's head and paste it onto the body of an extremely obese person. In many instances, ads would include testimonials of weight loss in ranges that well exceed a pound a day for time periods of 13 days or more. These claims ranged from 22 pounds in 13 days to 120 pounds in 7 weeks. These figures would require daily calorie deficits of 5,923 calories and 8,571 calories, respectively - both of which are physiologically impossible, as complete fasting could not even provide this level of weight loss.

Such deceptive advertising is damaging in that it encourage people to purchase ineffective products, and that it contributes the consumers' unrealistic notions about how easy it is to lose weight, encouraging them to afford themselves overeating today in hopes of some "revolutionary" product that will strip them of their fat in the future.

Since Victorian times, family meal time has been a symbol of upward mobility and achieving middle class status. Family meals involve a range of activities which strengthens diet preferences, cultural values, and reinforces a particular family identity.

In the 1950's, prosperity in the US allowed the majority of the population to join the middle class. Survey research suggests that almost all children and adolescents had regular family meal time. Today, this number has dropped slightly, with 42% of 12-18 year olds reporting eating family meals 6 or 7 times a week, and 69% on four or more days.

Today, less effort goes into food preparation, with many families eating fast food meals together, frequently in front of the television. There is numerous research showing that home-prepared foods are more nutrient-rich than food prepared out of the home.

A study of elementary school children showed a significant positive association between blood cholesterol levels and the number of times children reported eating in a restaurant each week.

Much of the anti-obesity effort is invalidated by social boundaries. Today, socio-economic status is a strong inverse predictor of obesity. In US households making less than $15,000 per year, 31% of the women are obese. In households making more than $50,000, only 17% are obese.

This is largely due to the fact that high-calorie foods are the least expensive foods, and the most resistant to economic fluctuations. The 2-year price change for low-calorie high-nutrient foods was +19.5%, whereas the price change for high-calorie foods was -2%. The sharp price increase for the low-calorie foods suggests an economic barrier to adoption of a more healthful diet.

This elevated cost of fast-food is significant, because recent reports suggest that 33% of kids in the US will be poor (less than $16,000 per year for a family of 4) at some time in their childhood; 25% are born poor; 20% are currently living in poverty. This is compared, for example, with 13.5% in Canada, and 2.7% in Sweden.

Despite the significance of food costs, lack of education poses an even greater obstacle for mothers to recognize obesity in their child. Mothers with less education were only able to recognize obesity in their children 11% of the time. Obese mothers of non-white children were even less likely to feel overweight than obese mothers of white children. Even among mothers who identified their child as overweight, only 2/3 said that they were worried about their child's weight.

Although most public anti-obesity programs fall short of their goals, public programs remain to be a very good investment for virtually any organization - at least, ideally. A recent study by the Trust for America's Health (TFAH) found that an investment of just $10 per person per year in proven community-based disease-prevention programs could save the country more than $16 billion annually within 5 years.

Early Childhood Interventions (ECIs) have demonstrated consistent positive effects on children's health and well-being. ECIS in the first 5 years of life show links to a broad range of positive outcomes up to 3 decades later, including better reproductive health and birth outcomes, higher cognitive skills, school achievement and performance, higher school attainment, higher earnings capacity, and lower rates of delinquency and crime.