WASHINGTON — Although many trendy diets try to limit carbs, not all carbohydrates are the same. Most of the weight gain anxiety dieters get revolves around the belief that eating “fast carbs” will make you fat. However, a new study finds there’s really no difference between fast or slow carbs when it comes to weight gain — or weight loss.
In a report commissioned by the Grain Foods Foundation, scientists discovered little difference in how high-glycemic and low-glycemic foods impact weight management. The glycemic index (GI) ranks how quickly a certain food raises blood sugar levels. The theory is that high-GI foods raise glucose levels and insulin secretion, which may lead to health issues through overeating.
Moreover, scientists believe high-GI foods promote fat storage and increase a person’s obesity risk. However, a review of nearly two million adults across 34 previous studies finds the impact of fast carbs is no more harmful than slow carbs.
“This study is the first to definitively demonstrate that fast carbs do not make you fat,” says study co-author Glenn Gaesser, PhD, a professor of exercise science in the College of Health Solutions at Arizona State University, in a media release. “Contrary to popular belief, those who consume a diet of high-GI foods are no more likely to be obese or gain weight than those who consume a diet of low-GI foods. Furthermore, they are no less likely to lose weight.”
The study authors add that “GI, as a measure of carbohydrate quality, appears to be relatively unimportant as a determinant of BMI or diet-induced weight loss.”
Fast carbs, slow carbs both ‘have a place on a healthy plate’
In 27 of those studies which compared the differences between high and low-GI foods, 70 percent showed that a dieter’s BMI was either the same or actually lower among people eating high-GI foods. Eight studies added that low-GI foods (slow carbs) were no better than fast carbs for weight loss or burning fat.
“The review questions the premise that low-GI diets lead to substantially better weight control outcomes and reminds us of the many other qualities of carbohydrates that are far more important to consider: for example, nutrient density, dietary fiber and whole grain content, and percentage of added sugar,” says Siddhartha Angadi, PhD.
“The key takeaway is that carbohydrates, regardless of type, can be part of a healthy diet and have a place on a healthy plate,” adds Miller Jones, PhD. “Over the past few decades, we’ve seen the blanket vilification of carbs, processed foods, and foods made with refined grains. Science has shown that these foods in the right balance can be part of a dietary pattern that can promote a healthy weight and reduce disease risk.”
“The truth is that eating a wide variety of carbohydrates, from fast-carb white bread to slow-carb bran flakes and pairing them with smart choices from all the food groups can provide the nutritional benefits that healthy carbs, especially whole and enriched grain staple. foods, can offer,” Jones concludes.
The findings appear in the journal Advances in Nutrition.