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Little-known skin facts

11 sourcesEvery line checked against its source

In short

Moisturizer works by sealing in water your skin has just taken in, so when you put it on matters.

Worth knowing11

  • "Unscented" does not mean fragrance-free: a maker may add just enough fragrance to hide the smell of other ingredients.

    U.S. Food and Drug Administration

  • "Hypoallergenic" has no legal definition in the US. It means whatever the company wants it to mean.

    U.S. Food and Drug Administration

  • No cosmetic is guaranteed never to cause an allergic reaction, whatever the label says.

    U.S. Food and Drug Administration

  • There is no official definition of "essential oils". Plant oils are treated like any other ingredient, and many are fragrance allergens.

    U.S. Food and Drug Administration

  • Manufacturers usually recommend discarding mascara two to four months after purchase.

    U.S. Food and Drug Administration

  • Exfoliating acids (AHAs such as glycolic acid) make skin burn more easily: in FDA studies, sun reddening rose by 18% after four weeks of use.

    U.S. Food and Drug Administration

  • That extra sun sensitivity from acids fades about a week after you stop using them.

    U.S. Food and Drug Administration

  • An acid on an ingredient list is not always there to exfoliate: small amounts are often used just to adjust the pH.

    U.S. Food and Drug Administration

  • A self-tan or bronzer is not sun protection unless it contains sunscreen and shows an SPF number.

    U.S. Food and Drug Administration

  • "Water resistant" sunscreen lasts 40 or 80 minutes in water or sweat (the label says which), not all day.

    U.S. Food and Drug Administration

  • The sun's UV rays can reach you on cloudy and cool days, and they reflect off of surfaces like water, cement, sand, and snow.

    Centers for Disease Control and Prevention

What helps3

  • Put moisturizer on while your skin is still damp after bathing, not after it has dried.

    National Institutes of Health

  • Shave in the direction your hair grows, not against it, to cut down on razor bumps.

    NHS website

  • Leaving at least 1 mm of stubble, instead of shaving as close as possible, can reduce ingrown hairs.

    NHS website

What to avoid7

  • Never wet dried-out mascara with saliva or water: it brings in bacteria and dilutes the preservative.

    U.S. Food and Drug Administration

  • Do not keep cosmetics above 85 °F, for example in a hot car: heat wears down the preservative.

    U.S. Food and Drug Administration

  • Store testers carry more contamination risk than your own products. If you try one, use a fresh single-use applicator.

    U.S. Food and Drug Administration

  • Do not use lip products around your eyes: some colour additives allowed on lips are not approved for the eye area.

    U.S. Food and Drug Administration

  • If you do not know how old your sunscreen is, discard it.

    U.S. Food and Drug Administration

  • Many spray sunscreens contain alcohol and are flammable: do not spray near a flame, a grill or someone smoking.

    U.S. Food and Drug Administration

  • Do not dip fingers into a moisturizer jar: use a clean spoon or a pump, so germs do not get into the whole tub.

    NHS website

Sources

Contains public sector information licensed under the Open Government Licence v3.0.

These pages describe what the sources say. They cannot say what is going on with your skin.

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