A nutritional composition for infants and young children comprising - an amount of at least 0.6 g oligofructose /100 kcal of said nutritional composition, or - an amount of at least 4 g/L of oligofructose when said composition is a ready-to-drink liquid composition, or - a sufficient amount of oligofructose to obtain at least 4 g/L of oligofructose in the reconstituted composition when said nutritional composition is a powdered or concentrated composition, wherein at least 90% of said oligofructose has a degree of polymerisation between 2 and 8, and wherein said composition comprises - less than 2 g oligofructose /100 kcal of said nutritional composition, or - less than 15 g/L of oligofructose when said composition is a ready-to-drink liquid composition, or - a sufficient amount of oligofructose to obtain respectively less than 15 g/L of oligofructose in the reconstituted composition when said nutritional composition is a powdered or concentrated composition, and wherein said composition comprises triglycerides with "high sn -2 palmitate", i.e. triglycerides having more than 33% of the palmitic acids in sn -2 position, and said composition comprises fat and at least 8% of said fat is "high sn -2 palmitate", for promoting or inducing a gut microbiota that is closer to the microbiota of infants fed exclusively with human breast milk, in infants or young children between 0 and 36 months of age, wherein said infants are born with a fragile or unbalanced microbiota or dysbiosis of microbiota, wherein said infants are preterm infants, infants born small for gestational age, infants born by Caesarean-section, hospitalized infants or infants treated or having been treated by antibiotics, wherein "promoting or inducing a gut microbiota that is closer to the microbiota of infants fed exclusively with human breast milk" comprises decreasing of the microbiota diversity to render it closer to the microbiota of infants fed exclusively with human breast milk, in comparison to the microbiota of infants fed predominantly with a conventional nutritional composition not comprising said oligofructose in said amount, wherein said composition promotes the growth of bifidobacterial and down-regulates the growth of peptostreptococcaceae bacteria, wherein said promotion and down-regulation affect the relative abundance of said taxa of bacteria. - an amount of at least 0.6 g oligofructose /100 kcal of said nutritional composition, or - an amount of at least 4 g/L of oligofructose when said composition is a ready-to-drink liquid composition, or - a sufficient amount of oligofructose to obtain at least 4 g/L of oligofructose in the reconstituted composition when said nutritional composition is a powdered or concentrated composition, wherein at least 90% of said oligofructose has a degree of polymerisation between 2 and 8, and wherein said composition comprises - less than 2 g oligofructose /100 kcal of said nutritional composition, or - less than 15 g/L of oligofructose when said composition is a ready-to-drink liquid composition, or - a sufficient amount of oligofructose to obtain respectively less than 15 g/L of oligofructose in the reconstituted composition when said nutritional composition is a powdered or concentrated composition, and - less than 2 g oligofructose /100 kcal of said nutritional composition, or - less than 15 g/L of oligofructose when said composition is a ready-to-drink liquid composition, or - a sufficient amount of oligofructose to obtain respectively less than 15 g/L of oligofructose in the reconstituted composition when said nutritional composition is a powdered or concentrated composition, and wherein said composition comprises triglycerides with "high sn -2 palmitate", i.e. triglycerides having more than 33% of the palmitic acids in sn -2 position, and said composition comprises fat and at least 8% of said fat is "high sn -2 palmitate", for promoting or inducing a gut microbiota that is closer to the microbiota of infants fed exclusively with human breast milk, in infants or young children between 0 and 36 months of age, wherein said infants are born with a fragile or unbalanced microbiota or dysbiosis of microbiota, wherein said infants are preterm infants, infants born small for gestational age, infants born by Caesarean-section, hospitalized infants or infants treated or having been treated by antibiotics, wherein "promoting or inducing a gut microbiota that is closer to the microbiota of infants fed exclusively with human breast milk" comprises decreasing of the microbiota diversity to render it closer to the microbiota of infants fed exclusively with human breast milk, in comparison to the microbiota of infants fed predominantly with a conventional nutritional composition not comprising said oligofructose in said amount, wherein said composition promotes the growth of bifidobacterial and down-regulates the growth of peptostreptococcaceae bacteria, wherein said promotion and down-regulation affect the relative abundance of said taxa of bacteria.