LNFP are fucosylated human milk oligosaccharides. The three isoforms of this pentasaccharide are built from lactose, fucose, and lacto-N-biose or N-acetyllactosamine arranged in different ways. Their function as prebiotic are under investigation.

LNFP‑I or ‑1; LNF‑I; Lacto‑N‑fucopentaitol‑I; LNF‑1; The fucose is α1‑2 linked to galactose in glucosamine (Fuc (α1‑2) Gal (β1‑3) GlcNAc (β1‑3) Gal (β1‑4) Glc).
LNFP‑I is regulated by fucosyltransferase‑2. It represents approx. 12% of the human milk oligosaccharide fraction in Se+/Le‑positive women and approx. 22% of Se+Le‑negative women (Kunz et al. 2017). milk groups

LNFP‑II or ‑2; Lea penta; the fucose is α1‑4 bound to N‑acetylglucosamine (Gal (β1‑3) [Fuc (α1‑4) GlcNAc (β1‑3) Gal (β1‑4) Glc].
LNFP‑2 is associated with the Lewis blood group gene and produced by fucosyltransferase‑3. It serves as "ligands for lectins, E‑ and L‑selectins and a natural killer receptor”. Milk samples of Se+/Le-positive women contain little LNFP-II (1.5%) because it competes with other HMO isoforms. In milk samples of non‑secretor/Le-positive women, LNFP‑II represents approx. 21% of the human milk oligosaccharide fraction (Kunz et al. 2017)

LNFP‑III or ‑3; Lex-lactose; LeX; The fucose is α1‑3 bound to N‑acetylglucosamine (Gal (β1‑4)  [Fuc (α1‑3) GlcNAc (β1‑3)] Gal (β1‑4) ). LNFP‑III is found in all human milk groups. Its amounts are lower compared with LNFP‑I or –II. That it is present in all milk groups indicates that other enzymes are involved (Kunz et al. 2017)