[Problem] To provide a skin-improving agent for oral intake, a collagen production promoter for oral intake, and a food product with which collagen production capability can be promoted by oral intake and which is highly safe in that it is natural and can be continuously taken orally. [Solution] The invention is a skin-improving agent for oral intake the purpose of which is to improve skin firmness, smoothness, wrinkles, and laugh lines, which is characterized in comprising the plant or extract of lingonberry (Vaccinium vitis-idaea) and alum (Phyllantus emblica or Emblica officinale); a collagen production promoter for oral intake, which is characterized in comprising the plant or extract of lingonberry and alum; and a food product characterized in comprising the plant or extract of lingonberry and alum.本發明之課題在於提供一種可經口攝取而促進膠原蛋白產生能力,且亦可持續經口攝取之源自天然且安全性較高的經口攝取用肌膚改善劑、經口攝取用膠原蛋白產生促進劑及飲食品。本發明係一種經口攝取用肌膚改善劑,其目的在於改善肌膚之緊致感、光滑度、皺紋及法令紋,其特徵在於含有越橘(Vaccinium vitis-idaea)及餘甘子(Phyllanthus emblica或Emblica officinale)之植物體或其萃取物;一種經口攝取用膠原蛋白產生促進劑,其特徵在於含有越橘及餘甘子之植物體或其萃取物;或一種飲食品,其特徵在於含有上述經口攝取用肌膚改善劑或經口攝取用膠原蛋白產生促進劑。