Read Full Story HSPH Professor Steven Gortmaker believes that there is a simple explanation for the globally skyrocketing rates of obesity in recent decades. It is now easy to obtain fast and cheap food at all hours of the day and night, giving eating a much lower “time-price” than in previous generations. People are exercising at about the same rate that they were 20 years ago, Gortmaker, professor of the practice of health sociology and director of the Harvard School of Public Health Prevention Research Center, told an HSPH audience on July 19, 2011, as part of the School’s Hot Topics series, but the food environment they face every day has changed.Constantly eating and drinking has become the norm, Gortmaker said. It is easier than ever to get cheap, high-calorie food and sugary beverages at all hours of the day and night, and kids are particularly vulnerable. Aggressively targeted by marketers of unhealthy foods and beverages, and surrounded by vending machines and fast food restaurants during the school day, unhealthy choices become their default.“We need to alter the environment where children spend their time so that it’s easy to make healthy diet and physical activity choices,” Gortmaker said. “You can’t just leave it to individual choice.” He said a good start would be to take unhealthy products out of vending machines at schools and make sure free water is available.