I never had skin tags, but I did use to get tiny hard skin bumps on my thighs and outer upper arms (AKA keratosis pilaris) every winter when I was eating SAD and low cal diets. It was not until I was reading one of ~100 LCHF accounts that someone mentioned that keto made their skin bumps disappear and I realized mine had disappeared too, despite the fact that keratosis pilaris is typically described as being "genetic" and "incurable".