<<Disclaimer:  Verify this information before applying it to your situation.>>

While there is a reason we are told not to feed solid food before a
baby is a certain age. However, that particular age varies from doctor
to doctor and child to child. My daughter did not receive solid food
until she was 6 months old, since she was premature and did not have
a mature digestive tract until that age.
        However, I have also known of children who began cereal in their
diets as young as six weeks, due to failure to thrive or other extenuating
circumstances.
        If you question why your ped has your baby start on solids, or a
bottle or anything else, ASK HIM WHY. If his answer does not satisfy you,
ask for a second opinion. Do not rely on standards to judge what your
child is or is not capable of. No child is the same.
        For that matter, if you question any medical advise, ask the
question. Advice from forums such as this should be a jumping point for
investigating your questions. It does not substitute for a ped or
GI who has seen your child and performed tests to find out what is really
going on. We are all individuals here, with different reactions and
different needs. The differences between the UK and US "Safe Lists"
illustrate this, if nothing else.

Sarah Rogers