What's Up with
Honey and Babies?
There is common advice that honey should not be given to a child under one year of age. Why is this?
The concern over honey is botulism and it applies only to uncooked honey.
Clostridium botulinum bacteria are found in about 10% of honeys in the U.S. Consumption of these bacteria almost never affects an older child or adult, but the immature infant intestine seems susceptible to colonization by this bacterium. As the bacteria multiply, it releases a potent toxin, (have you heard of Botox?). This botulism toxin affects the nerve endings in the body, causing paralysis, and can lead to death.
Not only in honey, the botulinum spores are very commonly
found in soil as well as in the dust in vacuum cleaner bags. The greatest
risk factor for infant botulism is not honey, but living on or near a farm.
The 
chief risk is in the first 6 months of life. Of course, the incidence of
botulism in infants is low and most babies exposed to honey or dirt will not
developclinical signs of botulism.
Studies suggest that the incidence of botulism may be greater in breastfed
babies, although their cases prove to be milderand cases of sudden death
from botulism are found chiefly in formula-fed infants. Some small
percentage of SIDS is thought to be related to botulism. It is possible that
the friendly breastfed infant flora may not compete well with botulinum
bacteria, although the rate of growth must be kept in check by breastmilk.
The iron in formulas causes a very vulnerable intestinal environment and may
be the cause of the more-overwhelming cases in formula-fed or
formula-supplemented infants.
Constipation, although a common finding in babies, can be an early symptom of botulism. If a baby develops constipation along with some weakness, such as reduced ability to hold his head up or to suck, these symptoms should be brought to the attention of a doctor.
References:
S.S. Arnon et al., Protective role of human milk against sudden death from
infant botulism, J Pediatr 100, no. 4 (Apr 1982): 568-73.
S.S. Arnon, Breast feeding and toxigenic intestinal infections: missing
links in crib death Rev Infect Dis 6, suppl. 1 (Mar-Apr 1984): S193-201.
P. McMaster et al., Instructive case: A taste of Honey, J Paediatr Child
Health 36, no. 6 (Dec 2000): 596.
J.S. Spika et al., Risk factors for infant botulism in the United States, Am
J Dis Child 143, no. 7 (Jul 1990): 828-32.