The role and efficacy of oral hyaluronic acid is minimal, and it does not play the role of wrinkle removal, filling and satiating the skin. Since hyaluronic acid is dissolved, digested and absorbed by various dissolving enzymes in the digestive tract after being taken orally, most of it is decomposed into carbon dioxide and water, in fact, in essence, the effect of oral hyaluronic acid is the same as that of the usual diet. Therefore it does not play the role of wrinkle removal that it achieves within the skin, and the role of making the skin smooth and full, and there are relatively few oral hyaluronic acid products. Hyaluronic acid is mainly divided into large molecules, medium molecules and small molecules, and the best effect is injected directly into the dermal layer of the skin by means of micro-needle injection, in order to make the skin full, full, smooth and hydrated, while oral digestive tract will directly break down the large molecules of hyaluronic acid into small molecules of nutrients, which does not play a good role in filling up the skin.