Ground walnut shell and apricot pit create irregular, jagged particles under magnification — particles with sharp edges that cause microscopic tears in the skin surface with every use. This is well-documented in dermatology literature and is the reason the AAD recommends against all physical facial scrubs with ground nut shell. Regular use progressively damages the skin barrier, increases sensitivity and reactivity, and can worsen acne by spreading bacteria through micro-tears. The “natural” origin of the ingredient does not make the physical damage less real.

Toners with denatured alcohol (alcohol denat.) or isopropyl alcohol as a primary ingredient are among the most barrier-damaging products in mainstream skincare. Alcohol works as an astringent by drying out and contracting skin — creating the sensation of “clean, tight pores” while actually stripping essential lipids from the barrier, disrupting the microbiome, and triggering rebound oil production. Long-term regular use of high-alcohol toners is associated with increased sensitivity, chronic redness, and accelerated barrier deterioration.

The FDA’s 2021 proposed rulemaking classified oxybenzone, octinoxate, homosalate, octocrylene, and several other chemical UV filters as “not generally recognised as safe and effective” (GRASE) — the same classification that would apply to an ingredient pending further safety review. The concern is primarily systemic absorption: these filters are measurably detectable in blood, breast milk, and urine after topical application. Oxybenzone specifically has shown endocrine-disrupting effects in some animal models, is banned in Hawaii for reef damage, and the FDA’s own testing showed blood concentrations exceeding the threshold for safety evaluation after just one day of use.

DMDM hydantoin works as a preservative by slowly releasing formaldehyde throughout the product’s lifespan. Formaldehyde is classified as a known human carcinogen by the International Agency for Research on Cancer. It’s also among the most common causes of contact dermatitis and allergic reactions in personal care products. Multiple class action lawsuits against hair care brands using DMDM hydantoin have resulted in settlements. Safer preservation alternatives (phenoxyethanol, sodium benzoate, potassium sorbate) achieve the same preservation without formaldehyde release. There is no reason to use DMDM hydantoin in 2026 when effective alternatives exist.

Pure Vitamin E oil (tocopherol at high concentrations) is one of the most highly comedogenic oils used in skincare — rated 4–5 out of 5 on the comedogenicity scale used by cosmetic chemists. Applied directly to the face as a standalone treatment or scar treatment, it frequently causes or worsens acne by clogging pores. Additionally, the clinical evidence that topical Vitamin E oil treats scars or stretch marks is extremely weak — a meta-analysis found no significant benefit for scar management versus placebo. Vitamin E is highly beneficial as an antioxidant in appropriately formulated serums at correct concentrations — it’s the pure oil applied liberally to the face that’s the problem.

A significant portion of products marketed as “brightening” contain no active ingredient capable of reducing hyperpigmentation or melanin production. “Brightening” is not a regulated term — any product can use it regardless of its actual ingredients. Products with brightening claims but no Vitamin C, niacinamide, kojic acid, azelaic acid, glycolic acid, or other evidence-based melanin-modulating actives are essentially doing nothing for dark spots or uneven tone beyond potentially improving general hydration. Before buying any brightening product, check whether it contains at least one evidence-based active at a meaningful concentration.

Silicone-based “pore-minimising” primers (containing high concentrations of dimethicone or cyclopentasiloxane) create the optical illusion of smaller pores by filling them with silicone — a visual effect that disappears when the product is removed. Over time, silicone buildup in pores causes congestion that makes pores appear larger than before you started using the primer, creating a dependency. The actual pore-minimising ingredients with genuine clinical evidence are niacinamide (reduces sebum production and thus pore diameter) and salicylic acid (keeps pores clear). These work on the pore’s actual size rather than optically filling it.

Topical collagen (hydrolysed collagen in creams and serums) cannot penetrate the skin and reach the dermis where collagen-producing fibroblasts live — collagen molecules, even hydrolysed, are far too large to penetrate beyond the stratum corneum. A “collagen cream” is a moisturising cream — nothing more. Additionally, products claiming to “boost collagen production” must contain a collagen-stimulating ingredient at a meaningful concentration to justify the claim. The evidence-based collagen stimulators are: retinol, peptides, Vitamin C (cofactor for collagen synthesis), and physical treatments like laser and microneedling. Cream formulas containing none of these but claiming collagen benefits are pure marketing.