Designed to help people with hair and/or scalp problems, this shampoo is relevant not only for what it does contain, sea kelp bioferment, but also for what it lacks: sodium lauryl (dodecyl) sulfate, a.k.a. SLS. SLS is the most common ingredient is shampoos and bath gels because it gives a lovely, bubbly, rich foam. But SLS is also a potent irritant, and people who have any kind of hair or scalp problems will be better off avoiding it. Use instead our fragrance free, mild shampoo.