When two people follow the same weight-loss diet to the letter, but one fails to lose weight, the problem might be their bodies’ different responses to the same foods, a recent Israeli study suggests.
That’s because when two people eat the same meal, one may experience a spike in blood sugar levels when the other person doesn’t, the study found. Over time, elevated blood sugar can lead to health problems like obesity and diabetes.
Many popular diets such as Atkins, The Zone and South Beach center on a component known as the glycemic index (GI), a fixed ranking of foods based on how fast and how high they raise blood sugar after meals. The index was originally developed to help people with diabetes choose foods that wouldn’t cause blood sugar to rise too high.
The logic behind the weight-loss diets is that consuming foods with a lower GI like fish, lean meat and vegetables can help keep blood sugar low and promote weight loss.