Post by Allison Aubrey, The Salt at NPR Food (2/20/13)
If you're prone to outbreaks of acne, you may want to try cutting back on empty carbs and sweets. Researchers are revisiting the connections between diet and pimples, and a growing body of evidence suggests that eating a diet rich in high glycemic index foods may be tied to flare-ups.
"High glycemic index foods are typically processed foods, high in white flour," explains nutrition researcher Jennifer Burris of New York University. Examples include white bread, pasta, crackers and white rice. The glycemic index is basically a system of measuring how fast your blood sugar rises after eating a specific amount of carbohydrates, so sugary foods such as soda, juice and candy bars are all on the list, too.
In a paper published in the Journal of the Academy of Nutrition and Dietetics, Burris and her colleagues review 27 studies on nutrition and acne. Some of the more convincing evidence comes from a few recent studies of teenagers and young men (aged 15-25 years) who had acne. After the participants followed a low-glycemic-load diet, researchers documented decreases in inflammatory acne lesions. The studies were small, but the findings were significant.
So what explains this connection? Researchers say foods that spike blood sugar can also increase hormones. The hormones can stimulate oil production, which in turn, can trigger acne. "It's like a domino effect," says Burris.