But some experts said that because of the specific diet plans used in the study, the results are far from conclusive in determining the "best diet."
"The study has important technical flaws," said Dr. Neal Barnard, founder and president of the Physicians Committee for Responsible Medicine. Specifically, Barnard pointed to the study's use of a "low-fat" diet plan, "which is not low in fat at all."
Rather than a traditional low-fat diet plan — such as the Ornish Diet, which designates that only 10 percent of calories should be derived from fat — researchers assigned subjects in the low-fat diet group to a plan based on the American Heart Association guidelines, which derives 30 percent of its calories from fat.
According to Barnard, the heart association guidelines for a low-fat diet are "very similar to the current U.S. average" for the amount of calories derived from fat in a diet.
"I fear that this study will be reported as a reason to load on the fat and cholesterol," Barnard explained. "In truth, none of the groups actually followed a low-fat regimen."
In addition, some experts pointed out that the low-fat diet did not meet the traditional goal of increasing carbohydrate and fiber intake, which is required in order to see any weight loss or cholesterol-lowering benefits of the diet.
"I do not think the diets met the stated goals; the 'low-fat' diet did not change the percent of fat in the diet or increase the carbs, as would be expected," said Dr. James Anderson, professor emeritus of medicine and clinical nutrition at the University of Kentucky. "It is difficult for me to draw conclusions from this study."
ABC News Medical Editor Dr. Timothy Johnson said he believes this study actually shows that there is no clear-cut "winner" among the diets compared.
"I'm amazed at all the hoopla over the diet," said Johnson on Thursday's Good Morning America. "There were 300 people [in the study]. They were in a controlled company environment where the cafeteria cooperated. They had registered dietitians even with all that help, at the end of a whole two years the best [weight loss] was 12 pounds? I mean, that's nothing, and 12 pounds versus 10 pounds [is a] two-pound difference, and you call that a winner?"
But regardless of the shortcomings of this research based upon the specific diet plans used in the study, many experts say there is still a great deal of good information to be taken away from this.
Dr. David L. Katz, director of the Prevention Research Center at the Yale University School of Medicine, said the study highlights that weight loss can be achieved in a number of different ways, and rather than focusing on one single diet plan, the better approach is to take the best elements of each diet and combine them into a plan that works for the individual with specific health needs.
"We can do better than a beauty pageant approach to diet and weight loss, and actually pull together what we know about diet and good health," Katz explained. "Sure, cut some carbs — but only refined starches and simple sugars. Sure, cut some fat — but focus on trans fat and saturated fat. Sure, adopt a Mediterranean diet, but go easy on the refined pasta or white bread, and be sure to control calories."