A new documentary movie, Fed UP, released May 9 and a New York Times Editorial published today are helping to focus the country’s attention on a new paradigm for what makes us fat and the importance of added sugar in causing obesity and chronic diseases. I highly recommend both viewing the movie and reading the editorial.
As I’ve pointed out here and here and as eloquently summarized by Gary Taubes in “Good Calories, Bad Calories” and “Why We Get Fat”, the concept of replacing fat with carbohydrates is not making America healthier.
The NY Times editorial and an article published by the same authors in JAMA focus on an alternative view of why people get fat. The generally accepted view is based on the (seemingly immutable) first law of thermodynamics, that you gain weight because you have consumed more calories than you have burned with exercise. People get fat due to lack of willpower in either consuming too many calories or not exercising enough. In this paradigm, all calories are equal in their effects. To lose weight you merely need to cut back on how many calories you consume. Unfortunately, calorie restriction for weight loss fails almost all the time.
The alternative view of obesity posits that underlying genetic factors exacerbated by lifestyle factors such as inadequate sleep, stress and by poor quality of diet are the major reasons for obesity. These factors lead to increase in fat storage which , in turn, means less metabolic fuels available for activity. This causes an increase in hunger and a reduction in metabolic activity, muscular efficiency and physical activity. The combination of increased energy intake and reduced energy expenditure causes obesity.
Insulin is the major hormone involved in fat metabolism and of all the things we eat highly refined and rapidly digestible carbohydrates cause the greatest insulin response. Thus, the authors write
By this way of thinking, the increasing amount and processing of carbohydrates in the American diet has increased insulin levels, put fat cells into storage overdrive and elicited obesity-promoting biological responses in a large number of people. Like an infection that raises the body temperature set point, high consumption of refined carbohydrates — chips, crackers, cakes, soft drinks, sugary breakfast cereals and even white rice and bread — has increased body weights throughout the population.
Fed Up, the movie, focuses on how American diets became awash in added sugar and what the consequences of that has been. Dr. Robert Lustig a pediatric endocrinologist at the University of California, San Francisco is an advisor to the film and has spoken and written eloquently on this new paradigm for obesity and the dangers of processed food, fructose and sugar as in this video.
Here’s the trailer for Fed Up.
The film has a limited release and may not be showing in your town, but you can check out some actions the film’s web site proposes (supporting a proposed tax on soda and sugary beverages, investigating your school’s nutrition policy, taking a 10 day no-sugar challenge) here.