I just wanted to add to this post, being an immunologist & having had a dh have stomach surgery just when I was weaning ds#1, I got the opportunity to add information from a dietician & gastroenterologist to my knowledge on food allergy & there are strong reasons for the recommendation of solids not before 6 months & defintely not before 4 months & only then in exceptional circumstances!
Strong reasons for holding off,
many babies intestines are not ready for solids & it can cause tummy problems (unsettled nights)... the food can not be sterilised like formula or breast milk
Most babies "know their appetite" for milk but solids can confuse them & cause overeating... which can be a possible cause of obesity in later life
Introducing some solids "early" can result in the baby being "intolerant" to the food, that if they "tasted" it later, they would have no reaction
Finally commercial baby food is relative new to the solids "game" & there is no long term research into how this affects things like obestiy gastrointestinal disorders etc etc... so encouraging people to start later, means they start later on the jarred food too & may eliminate some of the problems commercial food may cause.
All that said most babies will tolerate around 4 months... but if that was the recommendation some people would introduce at 2-3 months & babies intestines are not ready for food at this stage
The Gastroenterologist we saw (for my dh) said to me (as an aside) as I had a big baby 10kg (22lb) at 5.5 months he thought it would be fine to intorduce solids then but only do rice cereal & fruit & veg I had prepared myself for as long & as much as possible!! I held off until 6months, even though I had to do a night feed again!
