Every night before my son goes to bed, I put a dissolving tablet of dust and grass under his tongue. It’s his allergy treatment. The idea is simple: tiny, repeated exposure will teach his immune system not to overreact. In allergy medicine, this logic is trusted enough to prescribe it. By mouth, it’s called sublingual immunotherapy. By needle, it becomes allergy shots. Over time, the body can typically be trained by steady, careful contact with the thing it fears.
For years, parents were told to delay potentially allergenic foods like eggs or peanuts, especially if allergies ran in the family or if the baby had eczema. The entire conversation around food allergies taught families to think of certain foods as threats first and nourishment second. This was not fringe advice traded among anxious parents online—in 2000, the American Academy of Pediatrics recommended delaying introducing eggs to a child’s diet until age 2 and peanuts until age 3 for “high-risk infants.” Parents who followed this advice were not being neurotic. They were doing what the experts told them to do.
Now the guidance is close to the opposite: Once babies are developmentally ready for solids, parents are told to introduce allergenic foods early and keep them in the diet consistently. This shift was shaped by authoritative studies and has since been reinforced by additional evidence suggesting that early exposure is likely protective rather than dangerous.
