Common skin care ingredients -- R

Resveratrol: antioxidant which supports and protects collagen; may also inhibit some mechanisms of aging by modulating gene activity.

Retinol: form of vitamin A; fat soluble; depending upon concentration, estimated to be approximately 10 times less effective than tretinoin; relatively unstable. May irritate skin in high concentrations.

Retinal: form of vitamin A; fat soluble; less effective than tretinoin; relatively unstable. May irritate skin in high concentrations.

Retinyl Palmitate: (also known as Vitamin A Palmitate); ester of retinol combined with palmitic acid, considered a more stable alternative to retinol or retinal for normalizing the skin's texture and helping smooth out fine lines. Less irritating than retinol.

Retinyl Palmitate Polypeptide: water soluble formulation of Vitamin A.

Rose Hips: botanical extract of the fruit of the rose plant found to have high concentrations of vitamin C.