The potato board is, of course, gleefully promoting the findings of a recent study published in the September 2007 issue of the American Journal of Clinical Nutrition concluded what dietitians have been saying for decades: when it comes to losing weight, it is calories -- not the glycemic index of foods -- that ultimately makes the difference.
"Researchers from Harvard and the State University of Rio de Janeiro in
Both diets included a mild energy restriction (i.e., 100-300 fewer calories per day) and had similar macronutrient distributions (i.e., carbohydrate, protein and fat); all that distinguished the two diets were the GIs of the foods.
The high GI diet contained a hefty dose of... commonly identified high GI foods (e.g., [potatoes], bananas, watermelon, rice and white bread) while the low GI diet contained large amounts of beans and other low GI foods (e.g., apples, pears, oats, and sweet potatoes).
At the end of the 18-month period both groups had lost weight and there were no significant differences in weight loss between the two groups."
Some people might think, "So if it's all about calories, why do you and other nutritionists always talk about how important is to eat whole grains, vegetables, fruits, and legumes? Why not just tell people to eat whatever they want as long as they are reducing calories?"
Simple -- nutrition isn't just about weight loss.
Eating healthy is about feeding our bodies adequate amounts of vitamins, minerals, and other nutrients.
Someone consuming 2,000 calories a day would certainly lose weight eating 1,500 calories' worth of ice cream, soda, and Doritos.
However, they would be deficient in a plethora of vitamins and minerals, as well as fiber, Omega-3 fatty acids, and high-quality protein.
The advantage of low-glycemic foods, though, is that, for the most part, they help stabilize our blood sugar and energy levels.
They also tend to satiate us faster than foods with higher numbers, thereby making it easier to consume less calories.
The one instance in which the glycemic index plays a major role is when planning the diet of someone living with diabetes, as keeping accurate track of blood sugar levels is key for successful maintenance.
It's a shame to eliminate nutritious and delicious foods like potatoes, bananas, and watermelon out of your diet only because of their ranking in the glycemic index.