Lightweight Scalp Serum

The base most products are built on. It carries the other ingredients and has no safety concern.

A humectant that draws water into the skin. One of the best-studied, best-tolerated ingredients in personal care.

A corn-derived solvent and humectant that has largely replaced propylene glycol in "clean" formulas; CIR reviewed the alkane diol group and found use concentrations up to about 40 percent in leave-on products like deodorant sticks with no meaningful irritation signal.

A glycol used very widely in Korean and Western skincare as a lightweight humectant, solvent, and gentle preservative-booster, often in place of traditional preservatives. It has a low reported irritation rate at use levels and is graded low concern in published assessments.

A form of vitamin B3 used to support a more even-looking tone and a comfortable barrier. Well tolerated at cosmetic levels.

A soothing humectant that helps skin and hair look conditioned. Very well tolerated.

A cellulose derivative used to thicken and stabilize formulas. It dissolves fully in water and does not separate or settle over time. It is well tolerated and widely used in gels, lotions, and serums.

A starch derivative used in cosmetics to thicken formulations and improve texture. It has been used safely in food and cosmetics for decades and shows low irritation potential across rinse-off and leave-on products.

A preservative derived from caprylic acid (coconut-sourced) with antimicrobial activity that supports formula stability. Available data support its use at cosmetic concentrations.

A nutrient-dense plant oil rich in carotenoids and omega fatty acids, valued for skin conditioning and barrier support. Generally well tolerated, though as a botanical extract it carries the potential for contact allergies; users with sensitive skin or plant allergies may want to patch test.

A fast-evaporating solvent used to carry actives and give toners a light, "clean" feel; at the concentrations used in classic astringents it can be genuinely drying or irritating with repeated use, especially on dry or compromised skin, though it is not inherently toxic and is a normal, well-studied cosmetic ingredient.

A basic amino acid naturally found in skin that draws moisture into the stratum corneum. It is well tolerated in cosmetics at typical concentrations and has been used safely in skincare formulations for decades.

A larger, gentler alpha hydroxy acid than glycolic acid, used to exfoliate and to draw in moisture. It can still cause stinging or increased sun sensitivity at higher concentrations, so daytime SPF use is sensible, but it is generally better tolerated than glycolic acid.

A widely used, gentle preservative also common in food. It is generally well tolerated, though it can occasionally cause mild, transient irritation in people with already-compromised or very reactive skin.

A metabolite produced through fermentation of milk by Lactobacillus bacteria, valued in skincare for humectant and antioxidant properties. It is documented in cosmetic formulations as well tolerated, though people sensitive to fermentation byproducts or lactic acid may want to patch test.