1) Sodium Laureth Sulfate & Sodium Lauryl Suflate or SLS for short: to put it point blank, this is a detergent. It's what creates the the foam and bubbles in foaming cleansers. It's also in shampoos, soaps, bubble bath, etc. Now needless to say if you've already read my Cleansing Properly post (you can read that here), you'll know why you should avoid this kind of ingredient." It's actually a well known skin irritant, to the point where it's used as model irritant in dermatological studies.
“[Sodium lauryl sulfate] is such a consistent irritator for skin with an impaired barrier that it is actually used in ‘challenge patch tests’ to evaluate the barrier function of skin…it strips the natural lipids from the skin, disrupting the barrier and rendering it more susceptible to external irritants." -Dr. Leslie Baumann’s, Cosmetic Dermatology.
So my advice? Avoid this ingredient like the plague (at least for your skin, not your kitchen dishes :P). I'd highly suggest going SLS free in your shampoo and shower gel too if possible. I noticed a huge difference when I switched shampoos, specifically 50% less hair fallout and my hair was not as dry. If you want SLS free shampoo, I'd recommend Marc Anthony (if you're in Canada) and the L'oreal Professional Line internationally, they have a few good SLS free shampoos. And for body wash and/or hand soap - any soap/showergel from Dr. Bronner is a good one.
2) Alcohol, Alcohol Denat, Isopropyl Alcohol, and Ethanol: this one is to be proceeded with caution. Rule of thumb: if it's in the top 10 ingredients on the ingredient list, avoid. If it's near the bottom of the ingredient list - there's very little of it in the formula, so it's fine. These are all drying alcohols. If used in high concentration, they will dry out your skin. If there's not too much of it/ it's well formulated, it will aid in the absorption of skincare actives.
Also, quick note: not all forms of alcohol are drying! There are also fatty alcohols, such as cetyl alcohol and cetearyl alcohol. They are used to thicken formulas and add slip to the product and are harmless.
3) Mineral Oil (listed as/also known as - liquid paraffin, pariffinum liquidum, and liquid petroleum in ingredient lists): this is a very controversial ingredient in the skincare world right now. There are two sides to the argument: the first side says it's totally fine and does a good job at moisturizing the skin, whereas the other half says it just sits on top of the skin and clogs your pores. I'm on the latter side. I did an experiment where I went mineral oil free for a good few months, and my skin thanked me for it! I used to get little white heads on my cheeks, forehead, and nose, and when I gave up the ingredient they went away forever. Also reduced blackheads.
Mineral oil works by coating the skin, rather than being absorbed. It's an incredibly cheap ingredient (so if it's in your super expensive moisturizer - you're being ripped off big time) that is derived from petroleum—as a by-product of the distillation of petroleum to produce gasoline.
That being said, some people don't break out from mineral oil and swear it does wonders for their dry skin. My advice? Try going mineral oil free for a good 2 months and see if you notice a difference. But overall, I would still say avoid.
4) Oxybenzone: I mentioned this already in my sunscreen/sunprotection post (here), but I'll just quickly repeat myself. It's a form of chemical sunscreen that is officially known as a hormone disruptor, avoid at all costs! Unfortunately, several well-known brands still use this ingredient.
If you have any questions on the safety of other ingredients that weren't mentioned, leave a comment down below! :)
Next time on the Skincare Guide: Korean Skincare