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Results: Collagen becomes sparser and less soluble in intrinsically aged skin, but is thickened and more soluble in extrinsically aged areas. Elastin is degraded slowly and accumulates damage with intrinsic aging; also, increased synthesis of abnormally structured elastin occurs in photoexposed areas. This leads to an age-related accumulation of aberrant elastoic material, clumped in the papillary dermis. Generally, age leads to increased folding and decreased interaction of proteins with water. Also, despite increased GAGs in aged skin, these are abnormally deposited on the elastoic material and cannot interact properly with water. Hence, in aged skin, water is found in the tetrahedron form, bound to itself rather than other molecules. Lipid content appears to decrease with age, although the proportion of different lipid classes seems to remain fairly constant.