Geraghty says that there is some connection between diet and skin—with some caveats. "The best evidence we have so far suggests that what is called a high-glycemic index diet could actually worsen acne in people prone to it," she says. A high-glycemic index diet is one that's heavy in simple carbohydrates (like white rice, pasta, and bread). Because these carbohydrates are already pretty close to sugar, your body doesn't require a lot of energy to process them, leading to a spike in blood sugar and then a crash. It's unclear exactly why high-glycemic foods have this effect on acne-prone skin (and these foods certainly don't CAUSE acne) but research has shown that eating lots of these kinds of foods could contribute to breakouts if you're already an acne sufferer.
As for dairy products, Geraghty says that there is some evidence to suggest that certain types of dairy can cause acne flare-ups in acne-prone skin. While there is not a ton of research yet out on the subject, she says that the most recent studies seem to indicate that skim milk might be worse for the skin than higher-fat milk. However, she says that dermatologists don't recommend anyone dramatically change how much dairy they're eating just because of their skin—especially since dairy has so many important nutrients essential for young women.
Keep in mind that both of these foods seem to only adversely affect people who already have problems with acne. If you don't have acne at all, don't cut these foods out of your diet for the sake of your skin. "You could have a terrible diet and no acne, or you can have a perfect diet and break out," Geraghty says. "But if you are one of those people who tends to break out, it's a good idea to maybe adopt one of these low-glycemic index diets to help your skin, and maybe avoid excess dairy as well."
One thing you definitely don't need to worry about: gluten. "So far there's no compelling research that I've seen that's persuaded me that gluten has anything to do with acne," she says. "So if you like gluten, don't make yourself crazy!"
This article originally appeared on Women’s Health US.