Page 230 - Cosmetology

lempuyang extract. A form of ginger. There is no research showing it to be effective or have benefit for
skin.

Lentinus edodes extract. Extract from the shiitake mushroom that may have antimicrobial and antibacterial
properties, although it could be a potential skin irritant. There is research showing it also has antitumor
activity when taken orally.

Leptospermum scoparium oil. See manuka oil.

lettuce extract. See manuka oil.Has weak antioxidant and anti-inflammatory properties.

leucine. Amino acid. See amino acid and natural moisturizing factors.

leukocytes. White blood cells. These defend the body against infecting organisms and foreign agents, both
in skin and other tissue and via the bloodstream. An abnormal increase in the production of leukocytes is
known as leukemia. Conversely, a sharp decrease in the number of leukocytes (leukopenia) prevents the
body from fighting infection. There is no research showing that topical application of leukocytes is helpful for
skin in any way.

Levisticum officinale root extract. Amino acid. See lovage root extract.

licorice extract. Has anti-inflammatory properties.

licorice root. See licorice extract.

lignoceryl erucate. Form of erucic acid. See erucic acid and fatty acid.

Lilium candidum bulb extract. Derived from the white lily bulb. There is no research showing this to have
benefit for skin.

lime (oil or extract). Can be a skin irritant and a photosensitizer.

Limnanthes alba. Commonly known as meadowfoam seed oil, a non-volatile plant oil used as a skin
conditioning agent.

linalool. Fragrant component of lavender that can be a potent skin irritant, allergen, or sensitizer. Current
research indicates that this component of lavender can be cytotoxic (meaning toxic) to skin cells.

linden flower extract. Major active constituents in linden are flavonoids and glycosides. Flavonoids are
potent antioxidants and glycosides are monosaccharides and have water-binding properties.

Linoleamidopropyl PG-dimonium chloride phosphate. Used as an emulsifying and emollient ingredient
in skin- and hair-care products. Has antistatic properties when used on hair.

linoleic acid. Unsaturated fatty acid used as an emollient and thickening agent in cosmetics. There is some
research showing it to be effective in cell regulation and skin-barrier repair, as well as an antioxidant and an
anti-inflammatory.

linseed oil. Linoleic acid is a component of linseed oil. See linoleic acid.

Linum usitatissimum extract. See linseed oil.

lipid. Wide range of ingredients found in plants, animals, and human skin. Lipids include fatty acids, sebum,
and fats. In skin-care products, these are emollients and thickening agents. See fatty acid and natural
moisturizing factors.

liposomes. Delivery system (not an ingredient) capable of holding other ingredients and releasing them
after the liposome is absorbed into the skin. Liposomes are microscopic lipid (fat) sacs that are widely used
as a way to deliver other ingredients into skin.

lithium magnesium sodium silicate. Synthetic silica-based clay composed of lithium, sodium, and
magnesium. Used as a thickening agent and an absorbent.