Obesity affects close to 36 percent of U.S adults. Experts don't see obesity as a single-cause condition. Most medical experts contend obesity results from a combination of lifestyle and dietary factors that lead to energy imbalance. That said, research indicates the amount of fast food you consume plays a contributing role in developing obesity.
Researchers analyzed data from the Michigan Behavioral Risk Factor Survey and published the results in the July 2011 issue of the journal "Preventing Chronic Disease." The team found a strong link between how often residents consumed fast food and obesity prevalence. Michigan residents who consumed fast food once a month had the least risk. The study found that prevalence of obesity increased significantly for those who consumed fast food three or more times per week.
Researchers from New York University examined the role of fast-food portion sizes in the growing obesity epidemic. The team found fast-food portion sizes exceeded government standards. The team notes bigger that portion sizes encourage people to eat more, and the excess calories make it difficult to balance energy with physical activity. The team concluded the trend toward larger portion sizes contributes to rising obesity rates. The study was published in the February 2002 edition of the "American Journal of Public Health."