U.S. retail sales of weight management products and services—including foods and beverages, meal replacements and diet aids and commercial weight management programs—will reach $38 billion in 2013 and $40.9 billion in 2016, according to “Weight Management Trends in the U.S.,” a new report from Packaged Facts, Rockville, MD. Foods and beverages represent the largest share of sales, at almost 80%. Over the past five years, nonetheless, sales of weight management foods and beverages have been on a declining trend—despite, or maybe because of—the nation’s continuing weight problem.

Almost 70% of adults and almost 32% of school-age children and adolescents are either overweight or obese, according to the latest government statistics. Between 1988 and 2008, the prevalence of obesity increased by 48% among adults and more than 72% among children and teenagers. Moreover, according to Simmons panel data from Experian Marketing Services, almost 39% of all U.S. adults, representing 87.8 million consumers, currently are watching their diet to either lose or maintain their weight.

The causes of the increased prevalence of being overweight and obese are interconnected and complex, including influences such as environment, psychological, cultural and socioeconomic factors as well as overeating, lack of exercise, slow metabolism and genetic makeup.

For marketers, the opportunity to help provide better responses to the nation’s obesity epidemic is expanding and as the battle of the bulge continues, the arsenal consumers use is changing. Commercial weight management programs such as Curves, eDiets, Jenny Craig, Healthy Wage, Medifast, Nutrisystem and Weight Watchers are expected to regain steam by 2015 as marketers offer new targeted programs.