Gl
Glycerin
GlycerinHydrator
The plain moisture-puller in almost everything, from drugstore cleansers to pricey serums. It may also shield skin from irritants.
What it does
Skin makes some glycerin of its own, and skin products have used it for many years. Its boost to skin moisture matters most in dry, cold weather, such as winter.
The evidence, graded
strongOne application of a ceramide cream lowered water loss through the skin, measured from two hours and held to 24 hours, and raised skin hydration over the same day. Hyaluronic acid creams improved skin hydration and elasticity when measured at 30 and 60 days. Neither source Drop has read measured how long barrier repair takes, so Drop sets no barrier-repair window.Pavicic 2011 · Journal of Drugs in Dermatology ↗
emergingFine together — glycerin and hyaluronic acid both help skin hold water, and polyglutamic acid is sold for the same job. If you only want one, glycerin is the one with evidence on skin behind it.Papakonstantinou 2012 · Dermato-Endocrinology ↗
emergingHumectants like hyaluronic acid and glycerin pull water into the skin's outer layer. A review notes they can also raise water loss, so they are usually paired with an occlusive moisturizer. Applying on damp skin and sealing is a sensible habit. No study Drop has read compared damp and dry application, or timed it.Purnamawati 2017 · Clinical Medicine & Research ↗
emergingGlycerin (glycerol) has been used in skin products for many years, and skin makes some of its own. A 2008 review reports that it improves skin hydration and barrier function and protects against irritating stimuli. It also reports that glycerin products help skin in conditions marked by dryness and a weak barrier, such as atopic dermatitis.Fluhr 2008 · The British journal of dermatology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Pairs worth knowing
Read more
Routines · 5 minOil Cleansing for Non-Acne-Prone Skin: Does It Work?Oil cleansing has a clearer case for dry and normal skin than for acne-prone. Here is when the method helps, when it does not, and how to pick an oil.Routines · 5 minSkincare for the Gym: Before, During, and After SweatSweat plus sunscreen plus friction is a recipe for breakouts and irritation. Here is what to do before a workout, during, and after to keep skin clear.
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