Breast Feeding and Sudden Infant Death Syndrome:
Prolactin, DHEA, Melatonin and SIDS
Copyright 2003, James Michael Howard, Fayetteville, Arkansas, U.S.A.
This is a response to: Archives of Disease in Childhood 2004;89:22-25
"Comparison of evoked arousability in breast and formula fed infants" which I
sent to the journal. Here are the "Results" and "Conclusions" from the article
and my response. I thought the readers here may be interested.
"Results: Arousal thresholds were not different between breast fed and formula
fed infants in QS. However, in AS breast fed infants were significantly more
arousable than formula fed infants at 2-3 months of age. There was no difference
between groups of infants when sleep period length was compared at any study.
Conclusions: Breast fed infants are more easily aroused from AS at 2-3 months of
age than formula fed infants. This age coincides with the peak incidence of
It is my hypothesis (1985) that the sleep-consciousness cycle is controlled by
interactions of melatonin and DHEA. (It has been demonstrated that DHEA is
involved in melatonin production and melatonin is involved in DHEA production.)
Basically, when melatonin is high, sleep occurs, when DHEA is high,
consciousness occurs. As is well known, quiet sleep alternates with active
sleep. I suggest this cycling is designed to maintain sufficient levels of DHEA
during sleep to maintain brainstem function during times of sufficiently low
DHEA that allow sleep. When DHEA is very low, quiet sleep occurs, when DHEA is
higher, during sleep, active sleep occurs. Prolactin is known to stimulate DHEA
production. The cycling of quiet sleep and active sleep involves the reduction
of prolactin by melatonin with prolactin rebounding in response to levels of
melatonin. The first sleep is the deepest, I suggest, due to the high levels of
melatonin at this time. As prolactin rebounds, DHEA is produced which begins to
decrease levels of melatonin as sleep progresses. This gradual reduction of
melatonin and increase in prolactin eventually reaches a level of DHEA which
induces consciousness and stops release of melatonin until DHEA production
decreases near nighttime and begins the cycle again. The connection between
melatonin and DHEA is prolactin.
Breast milk contains prolactin. I suggest prolactin occurs in breast milk to
stimulate DHEA. Therefore, prolactin in breast milk would activate DHEA
production, but not sufficient to induce arousal. This would combine with an
infant's DHEA to increase DHEA during active sleep. It is my hypothesis that
sudden infant death syndrome results from insufficient DHEA during quiet sleep
to maintain brainstem function. I suggest the evolutionary value of prolactin
in breast milk is decreased SIDS.
James Michael Howard