Hey thisisyesterday, thanks again for the many references! Not that I?m trying to pick holes, I?m just not sure that any of these papers show good evidence of harm in introducing solids from 4-6 months.
The results of Kramer et al show that breastfeeding reduced the incidence of GI infection ? that?s fine, other studies show this too, I can go with that.
The paper by Kajosaari & Saarinen from 1983 only looked at the children of atopic parents. Therefore their findings, if produced from sound research, can only be applied to the children of atopic parents, and not across the board. I?ve not been able to locate the original paper myself, but Kramer et al in the WHO publication state that confounding factors in their research were not controlled for, the researchers were not blind to the measurements they were taking and loss to follow-up was either more that 25% or not even reported in the paper. Again, their methodology was to compare babies started on solids at around 6 months with those started at 3 months, which is earlier than anyone?s advocating. All in all, not a great quality paper, findings as you say yourself not replicated in the study from Belarusse, not applicable to the general population and not really addressing the issue in question.
Wilson et al (1998) in the BMJ looked at introduction of solids at 15 weeks vs after 15 weeks, and did not find a significant association with respiratory illness or asthma, but did find a significant association with wheezing. However this study used data collected from a parent completed questionnaire, and does not define what is meant by ?wheezing?- different parents will have differing views on what wheezing is, so this could well have counfounded their results, aside from the recall bias inherent in using questionnaires. Again, as this study looked at solids at 15 weeks vs solids after 15 weeks, it does not tell me about harmful risks of introducing solids at 22 weeks.
The abstract of the DARLING study (Heinig et al 1993) says that morbidity did not differ between the two groups (early solids vs late solids), and that they found no difference in energy intake (which goes against the ?continue with breastfeeding as breast milk has more calories? argument) or weight gain between the groups either, so no benefits or risks were identified in that paper.
The abstract for Naylor et al states that ?there is no reason to conclude that exclusive breastfeeding should not continue to 6 months.? It says nothing about there being risks of the introduction of solids at 4-6 months rather than 6 months plus.
So I?m still unconvinced that there is credible research out there that says introducing solids at under 6 months poses significant long-term risks.
Blimey, now I?ve got brainache