Some irritating ingredients can also have positive results for skin, such as AHAs,
BHA, Retin-A, Renova, sunscreen ingredients, some antioxidants, and some preservatives
that keep products stabilized. All of those can be considered essential for many skin types
and product formulations, yet they do pose a risk of irritation. In this case, it’s simply a
tradeoff in which the positive benefits outweigh the potential negatives. On the other hand,
some ingredients are not only irritating but also have no positive impact on skin, meaning
they don’t help it in any way and are best avoided. Those are the ones I consistently warn
about and advise you to avoid.