You may have heard the advice that infants under one year of age should not have honey. This has nothing to do with sugar intake, but instead we are concerned about the possible presence of spores of Clostridium botulinum, the bacteria that causes the illness botulism. These spores can become active in an infant’s digestive tract and poison them with a toxin it produces.
Clostridium botulinum produces botulism toxin, which can kill even the most healthy adult. This bacteria can be found in soils and waters all around the world and grows best in low acid, low oxygen environments, which is why improperly canned foods are the most common example of how humans may encounter the bacteria and toxin. Canned foods are usually fruits or vegetable brought in from outside, where they may become contaminated by the bacteria, then when canned improperly, the bacteria can thrive and produce the toxin. Botulism toxin is the most potent toxin that we know of, when considering the amount needed to cause death.
Clostridium botulinum can form spores, which are a type of cell that has low biological activity so that it can withstand non-ideal conditions. These spores can be found in soil, dust, and water and can be spread by things like wind. If the botulinum spore ends up in more favorable conditions it can transition to become the active bacteria again, which will produce botulism toxin.
Since honey is a natural product, it can contain Clostridium botulinum spores if they happened to have been carried into the hive somehow. The spores will not turn active in the honey and produce the toxin (unlike improperly canned goods), which is why eating honey is not an issue for adults. However, the spores CAN grow in an infant’s immature digestive tract and begin to produce the toxin. An adult’s digestive tract is not hospitable for the spores to transition, so we are only concerned about infants in this scenario.
There is nothing special about honey that makes it particularly prone to cause infant botulism. Historically however, it has been a common source of poisonings because of infant feeding or soothing customs. The main source of infant exposure to botulism spores is through soil and dust from the natural environment. This of course is unavoidable, so honey (which is avoidable) has gotten the most attention.
If your infant is exposed to honey (I’ve inadvertently given it to my infants in marinades or dressings, it happens!), there is no cause for immediate concern. Infant botulism is still exceedingly rare, but it is always helpful to be vigilant and aware of the symptoms as quick treatment will save the child’s life. Symptoms occur within a day or so (though they may take longer, even weeks, to fully actualize) and include floppiness, poor feeding, drowsiness, constipation, and a weak cry. If you notice of these symptoms even without honey exposure, especially weakness and floppiness as it is seen in around 88% of cases (citation), get medical attention immediately.
Infant botulism is definitely a scary thing, but with the knowledge of both how it occurs and what symptoms to look for, we can better protect our children.