A review.Meadowestolide and meadowlactone are unique new functionally active ingredients for the effective treatment of skin that should be incorporated into pigmented products.The mol. configuration of these materials is quite dynamic, accounting for their ability to actively participate in tissue rehydration and conditioning.Meadowestolide may be functioning as a bioactive analog of ceramides.Meadowlactone may be functioning as a pH-sensitive isomer with dual lipophilic-hydrophilic character.Following the application of 2 to 3% Meadowestolide or Meadowlactone in a simple cream emulsion base, microphotog. images of skin provide clear visualization of improved tone, texture, and overall appearance.