An infant formula composition including fucoidan, a protein, and a lipid. The fucoidan may be partially hydrolyzed, and also may be sulfonated. The protein may be derived from quinoa. Also disclosed are infant formula kits to be assembled in the field. The kits may include a substantially dehydrated infant formula composition and a diluting agent. The kit may alternatively include a ready-to-consume infant formula composition and substantially dehydrated additives which may be added to the formula before consumption.