There is a great deal of speculation as to whether you can prevent allergies by eating honey. From a purely clinical standpoint, there is little evidence to support this idea. Anecdotal evidence ranges from complete support of the idea and testimonials to its success, to the many who have tried it and found it doesn’t work. Part of the reason for this conflicting information is that people are allergic to many different things, so honey might be effective for one allergen but not another.
The theory behind eating honey — generally raw, local honey from no more than 50 miles (80.47 km) away — is that if a person consumes pollen in the honey, he or she will gradually build up a tolerance to plants that are likely to cause hayfever. A similar remedy of eating honeycomb was popular in the 1970s, but hasn’t gained much in popularity since then. Someone who is allergic to dust mites or cat hair probably won’t solve the problem by eating honey, because it doesn't desensitize a person to such allergens in this way.
There are a few holes in the theory of honey working as a desensitizing agent. First, when an allergist gives allergy shots, he or she does so in extremely low doses, so that the patient gradually builds a tolerance to allergens. Honey, on the other hand, can contain relatively large amounts of pollen, generally much more than a person would be exposed to if he or she spent an hour or so outdoors. A person who is severely allergic to pollen might have an anaphylactic reaction to eating honey, though this is extremely rare. Alternately, honey simply might worsen the person's allergies. Others report no worsening of allergic response, but also no improvement in symptoms.
This had led to the theory that feeding honey to young people might help them avoid allergies later in life. In other words, exposure to large amounts of pollen present locally at an early age could desensitize people before they have a chance to really develop an allergic reaction. The problem here is that adults should never give honey to children under the age of 12 months, since it contains botulism spores, even when cooked, that can transmit the bacteria to babies. The risk is far too great and young children far too vulnerable to try this method for preventing allergies.
Feeding honey to older children might help, but it would require the children to live in the same location, or within 50 miles (80.47 km) of it, for the rest of their lives. People are often much more mobile than they once were, so this is not a scenario for most people. So while a child might have a tolerance to some pollens, he or she will still likely be affected by others that aren’t local. If the parent gives the child honey that's not local, then the child could still be allergic to local pollens.
Even though it is probably not possible to prevent allergies by eating honey, the substance does have some health benefits. It can be soothing to sore throats and help calm coughs. Honey is also helpful in providing “good” bacteria for the gut and can help with certain digestive problems. Some studies show that honey applied to burns may accelerate skin healing. Of course, many people find local honey to be a tasty addition to their diets, so as long as an allergist or other medical professional gives his or her approval, there's probably no harm in trying to treat allergies with it.