Any link between sugar and acne has long been dismissed. But now scientists are taking another look.
In recent years, studies have shown that what matters may not be sugar itself but a food’s glycemic index, or the speed and extent to which it raises blood glucose levels. Foods that have a high glycemic index — and as a result raise glucose levels rapidly — cause the body to release a flood of insulin and other hormones, which some scientists suspect can stimulate oil production and inflame the skin.
To test the theory, scientists recruited 50 men and boys ages 15 to 25, all of them with acne, and followed their progress for 12 weeks. Some subjects stuck to a typical diet that included high-glycemic foods like white bread, sweetened cereals and pasta, and the others were given foods higher in protein and lower on the glycemic scale, like fish, whole-grain breads and fruit.
At the end of the study, published in 2007, the subjects on the low-glycemic diet had far greater reductions in skin lesions and other symptoms of acne than the control group. They also showed reductions in their levels of free, circulating androgens, the male hormones known to cause acne, suggesting that hormones played a role.
Other studies have found similar connections between high-glycemic foods and acne, though scientists say more research is needed.
THE BOTTOM LINE
There is some evidence that foods high in sugar can worsen acne.