Contents

A light oil-in-water emulsion for skin below the neck. Body lotion is the highest volume product in this catalogue by weight sold, the cheapest per gram, and the one where the difference between an expensive and an inexpensive product is smallest.

Lotion, cream, butter, ointment

The distinction is water content, and it maps directly onto how dry the skin is.

Format Water Feel Right for
Lotion High (70–85%) Light, pumps, sinks fast Normal to mildly dry skin; large areas; summer
Cream Moderate Thicker, scoops or squeezes Dry skin; winter
Butter Low Rich, solid at room temperature Very dry skin, elbows, heels — see Body Butter
Ointment None Greasy, occlusive Eczema, cracked skin, medical use

More water is not less effective — it is a different job. A lotion spreads over a whole body in the time a butter covers one leg, and the moisturiser people actually use daily beats the one they own.

What is in it

Class Doing what Names
Water Bulk Aqua
Humectant Binds water at the surface Glycerin, urea, propylene glycol, sodium PCA
Emollient Smooths, softens Caprylic/capric triglyceride, shea butter, plant oils, isopropyl myristate
Occlusive Slows evaporation Dimethicone, mineral oil, petrolatum
Emulsifier Holds it together Glyceryl stearate + PEG-100 stearate, cetearyl alcohol
Preservative Essential Phenoxyethanol, benzyl alcohol, sodium benzoate
Fragrance The main reason people choose one Parfum

Urea deserves a separate note. At 5–10% it is a humectant; at 10% and above it is also keratolytic, softening thickened skin. It is the most useful single ingredient for rough heels, keratosis pilaris, and the shins of anyone over sixty, and it is underrepresented on the mainstream shelf outside pharmacy brands.

When to apply it

Within three minutes of getting out of the bath or shower, on skin patted rather than rubbed dry. Damp skin has surface water for the humectants to bind and for the occlusives to seal in, and the difference is measurable rather than folkloric.

Fragrance, plainly

Fragrance is the most common cause of contact dermatitis in this category and body lotion is applied to a very large surface area, daily, often on skin freshly stripped by hot water and surfactant. Anyone with itching that has no obvious cause should try a genuinely fragrance-free lotion for a month before anything else. Note that "unscented" is not "fragrance free" — unscented products may contain masking fragrance.

Where it sits in the rules

Cosmetic in the US — FDA primary category (14). Three routes to also being a drug: an SPF number, a skin protectant claim with a monograph active, or an eczema or psoriasis claim. Note also that the EU retinol restriction of Regulation (EU) 2024/996 sets a much lower limit for body lotion — 0.05% — than for face products, precisely because the applied surface area is so much larger.

Body lotion is also the format where "and other ingredients" occasionally appears at the end of a US ingredient list: that is the FDA-accepted trade-secret exemption under 21 CFR 701.3, and it is legal.

Shelf life

Twelve months after opening for a pump bottle; less for a tub. Separation, a sour or solvent-like odour, or a colour change means the emulsion or the preservative has failed. Bottles kept in a bathroom and topped up with water — a surprisingly common habit as they run low — are contaminated from that moment.