Researchers led by Hollie Raynor, a professor at the University of Tennessee, found that dieters who are restricted from eating a variety of junk food do not lose more weight than dieters without that restriction.
Raynor's team worked with 200 overweight and obese adults, splitting them into the two categories to test the idea that limiting unhealthy options could lead dieters to tire of those foods, resulting in better eating.
The group given only two options for junk food consumed fewer "junk food" calories, the team found, but did not lose weight at a rate greater than the group with unlimited options.
The reason was that the first group made up for the lost junk food calories with other types of food, researchers said.
"Limiting variety was helpful for reducing intake for that type of food group, but it appeared that compensation occurred in other parts of the diet," Raynor said.
Comments from experts suggest that portion control — like what is Bloomberg is advocating — must be an important part of weight loss, along with limiting unhealthy foods in a range of categories.
Members of New York's congressional delegation have been critical of the mayor's plan.
"I think it’s a bit too far," Rep. Yvette Clarke (D-N.Y.), who served in the New York City Council for the first five years of Bloomberg’s term, told The Hill.
“We do have an obesity problem, but where do we draw the line?" she said.
"Are we going to regulate how many cookies people can buy at the cookie shop? How many cakes people can buy at the cake shop? How many ice creams people can get from the ice cream shop? I just don’t know where you draw the line.”
Bloomberg defended his plan this week.
“There’s an epidemic in this country of people being overweight, bordering on obesity,” he said on MSNBC. “We've got to do something. Everybody is wringing their hands saying 'we've got to do something.' ”
He added that anyone interested in a sugary drink larger than 16 ounces could just buy two.