1. The use of a source of protein containing bovine casein proteins for the preparation of a nutritional composition intended for administration to an infant or young child experiencing a period of catch-up growth following a period of growth retardation, during or after a period of catch-up growth, to improve early growth and / or reducing the risk of developing insulin resistance or type 2 diabetes in the later stages of the life of an infant or young child. 2. The use according to claim 1, wherein bovine casein provides 40-100 wt.% Protein source. The use according to claim 1, where the infant is a premature baby or an infant who has undergone intrauterine growth retardation. The use according to claim 1, where the protein source contains both casein and whey proteins, and the casein: serum ratio is in the range from 70:30 to 30: 70.5. The use according to claim 4, wherein the whey protein is a sweet whey from which casein-glycomacropeptide is removed, and the composition further comprises free phenylalanine in an amount of up to 2.2%, free isoleucine in an amount of up to 0.92%, free tryptophan in an amount up to 0.34% and free histidine in an amount up to 0.19%, all in the form of wt.% of the total protein content. 6. The use according to any one of claims 1, 2, 4 or 5, where the energy value of the composition is 620-640 kcal / l. The use according to any one of claims 1, 2, 4 or 5, wherein the protein (s) is intact. The use according to any one of claims 1, 2, 4 or 5, wherein the nutritional composition further comprises lactose. The use according to any one of claims 1, 2, 4, or 5, wherein the nutritional composition further comprises a lipid source including linoleic acid (C18; 2n-6) and α-linolenic1. Применение источника белка, содержащего белки бычьего казеина для приготовления питательной композиции, предназначенной для введения младенцу или маленькому ребенку, переживающему период догоняющего роста, следующий за периодом задержки роста, в течение или по