The study, a collaborative effort between the University of California at Davis and the Illinois Institute of Technology, sought to gain a better understanding of the role of calorie reduction and the glycemic index in weight loss when potatoes are included in the diet.
"Some people have questioned the role of potatoes in a weight loss regimen because of the vegetable's designation as a high glycemic index food," explained Dr. Britt Burton-Freeman, PhD, the lead investigator of the study. "However, the results of this study confirm what health professionals and nutrition experts have said for years: it is not about eliminating a certain food or food groups, rather, it is reducing calories that count," said Burton-Freeman.
Ninety overweight men and women were randomly assigned to one of three groups: (1) reduced calorie/high GI, (2) reduced calorie/low GI, (3) control group with no calorie or GI restrictions. All three groups were provided potatoes, healthful recipes and instructions to consume 5-7 servings of potatoes per week. At the end of the 12-week study period, the researchers found that all three groups had lost weight and there was no significant difference in weight loss between the groups.
"There is no evidence that potatoes, when prepared in a healthful manner, contribute to weight gain. In fact, we are seeing that they can be part of a weight loss program," said Burton-Freeman.
Interestingly, even the control group reduced their caloric intake and lost weight despite not being provided with a specific calorie restriction. "The fact that all groups, even the control group, lost weight is a curious finding and provides cause for future research," said co-investigator Dr. Tissa Kappagoda, MD, PhD.
The study results are good news for potato lovers and any consumer who craves the satisfaction of wholesome yet healthy meal options. One medium-size (5.3 ounce) skin-on potato contains just 110 calories per serving, boasts more potassium (620g) than a banana, provides almost half the daily value of vitamin C (45 percent), and contains no fat, sodium or cholesterol.