Bex1982
Well-Known Member
"...The glycerin and baby soaps have the highest ph..."
Yeah. Go figure. I thought that was unusual too.
The "irritation index" in that particular list is based on skin patch tests done on sensitive individuals. According to the authors of that paper, most people are not bothered by soaps with a high skin irritation index, but for folks who are sensitive, any soap with an index over about 3.25 will probably be too harsh.
The authors also found a strong correlation (p<0.006) between skin irritation in sensitive people and the pH of the soap. The higher the pH, the higher likelihood of irritation. What's interesting to me is handcrafted soaps have about the same pH range as these commercial soaps, but my experience and what others say shows that most handcrafted soaps don't seem to be as irritating or drying as commercial soaps. Unfortunately, that's just an opinion -- objective research on handcrafted soaps is sorely lacking.
I make a lower superfat soap than most people, and my soaps are mild to the skin, so I'm also of the opinion that it's not entirely superfat that makes the difference. (Most commercial soaps made today have 0-1% superfat, just so's you know.) But I know plenty of soapers feel otherwise, and that's fine. Intelligent discussions about the finer points of soap and soaping are part of what makes soaping so interesting to me.
And most of them have the glycerin removed. I'm not totally sold on it being the same when they add "vegetable" glycerin to the soap. I suppose they are trying to make it more like real CP soap. I suppose the oils used would make a difference too. Commercial soaps will have their main oils be something really cheap and then add others just for appeal at super low %.
Maybe it's that whole boiling down and separating the soap that makes it harsher?
