November 26, 2013
Breast Milk Provides Infants With Iodine Essential For Development
Rebekah Eliason for redOrbit.com – Your Universe Online
The trace element iodine is an essential component in healthy bodies. It is especially important for the healthy development of babies. An iodine deficiency can cause disrupted growth and serious nervous system damage. There are regions of the world with iodine deficient soil such as Switzerland, where iodized salt is suggested as an important ingredient in cooking and the food industry.
In general, however, most infants receive all the iodine they need through breast milk and enriched baby food. Unfortunately, iodized salt and iodine enriched baby food is not available in all parts of the world. This is especially true in remote areas in developing countries.
In order to be sure newborns are receiving proper amounts of iodine, the World Health Organization (WHO) recommends that new mothers take a onetime dose of iodine in a capsule to store in the body all the iodine needed for mother and baby for an entire year. The iodine is passed on to the baby through breastfeeding. In cases where breastfeeding is not possible, doctors give a smaller dose of the iodine pill to the baby.
Recently, a new study was performed to test the effectiveness of these two methods. This is the first study to compare direct iodine administration with indirect administration through breastfeeding. The study also monitored the iodine levels in mothers and babies over a one year period. The researchers discovered that administering an iodine capsule to mothers is a more effective method than direct administration to the child - although both ways fell short of ensuring mother and baby received the proper amounts of iodine.
Raschida Bouhouch, PhD student in the Laboratory of Human Nutrition at ETH Zurich, along with her colleagues performed a blind study in Morocco that included 241 mother-baby pairs. For half of the pairs, the mother received an iodine capsule and the baby received a placebo while the other half of the mothers and babies received reverse parameters. The pills were given to the infants along with its first round of vaccinations in the first eight weeks that follow birth. In the following nine months, Bouhouch and colleagues performed measurements of breast milk and the urine of mother and child to determine how much iodine was present.
Even though mothers passed a surprisingly large amount of iodine to the child through breast milk, concentration of the element in the baby’s urine was still significantly lower than the critical threshold at nine months. The mother’s iodine levels were also deficient after the one time dose.
“The mother’s body is apparently programmed to put all its iodine reserves into nourishing the child and does not keep sufficient reserves for itself,” explained Bouhouch. Although the levels were below the minimum threshold, shortly after birth babies had better iodine levels than their mothers.
Babies who received iodine directly had even lower levels of the element than those receiving it through breast milk. This might be attributed to better absorption of iodine when it is passed through breast milk than when received in a pre-processed form.
Bouhouch emphasized, “That does not mean that direct iodine administration is not a good thing.” Since the thyroid requires iodine to function properly, both methods are beneficial for hormone production. Bouhouch believes the WHO’s recommendation should be altered since the onetime dose of iodine is only effective for six months instead of one year as previously thought.
Since one capsule fails to raise the mother’s iodine levels to a healthy level, “It would be better to give the mother’s iodine twice instead of only once a year,” she says. Even when giving iodine directly to babies, more frequent and lower doses were shown to be more beneficial. The new strategy of administering iodine capsules in conjunction with vaccines is a promising approach that is currently on its way to becoming an official recommendation.
Researchers led by Michael Zimermann, ETH Professor of Human Nutrition and director of this study, are currently investigating the process by which a high iodine dose is metabolized in children and mothers. This reaction in the body is not yet fully understood.