A lower risk of child-onset diabetes may be more applicable to infants who were born from diabetic mothers. The reason is because while breastfeeding for at least the first 6 months of life minimizes the risk of Type 1 diabetes from occurring in the infant, inadequate breastfeeding in an infant prenatally exposed to diabetes was associated with a higher risk of the child developing diabetes later on. However, it can be argued that human breastfeeding may contribute to protective effects against the development of Type 1 diabetes due to the fact that the alternative of bottle-feeding may expose infants to unhygienic feeding conditions. Though it now is almost universally prescribed, in some countries in the 1950s the practice of breastfeeding went through a period where it was out of vogue and the use of infant formula was considered superior to breast milk. However, it is now universally recognized that there is no commercial formula that can equal breast milk. In addition to the appropriate amounts of carbohydrate, protein, and fat, breast milk provides vitamins, minerals, digestive enzymes, and hormones. Breast milk also contains antibodies and lymphocytes from the mother that help the baby resist infections. The immune function of breast milk is individualized, as the mother, through her touching and taking care of the baby, comes into contact with pathogens that colonize the baby, and, as a consequence, her body makes the appropriate antibodies and immune cells. At around four months of age, the internal iron supplies of the infant, held in the hepatic cells of the liver, are exhausted. The American Academy of Pediatrics recommends that at this time that an iron supplement should be introduced, however, other health organisations such as the NHS in the UK have no such recommendation. Breast milk contains less iron than formula, because it is more bioavailable as lactoferrin, which carries more safety for mothers and children than ferrous sulphate. Both the AAP and the NHS recommend vitamin D supplementation for breastfed infants. Vitamin D can be synthesised by the infant via exposure to sunlight, however, many infants are deficient due being kept indoors or living in areas with insufficient sunlight. Formula is supplemented with vitamin D for this reason. Under the influence of the hormones prolactin and oxytocin, women produce milk after childbirth to feed the baby. The initial milk produced is referred to as colostrum, which is high in the immunoglobulin IgA, which coats the gastrointestinal tract. This helps to protect the newborn until its own immune system is functioning properly. It also creates a mild laxative effect, expelling meconium and helping to prevent the build-up of bilirubin (a contributory factor in jaundice).