Introduction of Solids - 4 months or 6 months?
So, we read a study*…
We have read and digested (pardon the pun!) a recent study which looked at the incidence of eczema or wheezing in later childhood and how when we introduce solids to our babies is important in this respect.
*see link to this research below.
Who recommends what? I’m confused.
American (AAP) and Canadian (CPS) national health bodies recommend the introduction of solids around 6 months onwards. The NHS does so too. But the European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN) says solids ‘should not be introduced before 4 months but should not be delayed beyond 6 months’ – essentially, you can introduce solids from 4 months. It can be hard to navigate this time of introducing solids, weaning, baby-led weaning, giving purees – whatever you want to call it – when there is conflicting information circulating. Our research, in line with current recommendations from our national health body as well as others mentioned above, tells us that 6 months onwards is sensible – though there are exceptions (see below).
Anecdotally, parents have been told by paediatricians and other health professionals that they can start solids from 4 months and we have seen this recommendation espoused even with premature babies too, when we know that the baby’s adjusted age should be used. This is concerning where there is no risk factor to indicate any benefit to early introduction. So, we thought we’d discuss this interesting research paper with you which confirms our view – and that of others – that introducing solids from 6 months is generally recommended.
This study
This recent study followed over 7000 children over a period of almost 8 years.
They explored the differences between introducing infant cereal to babies at 4 months or 6 months and what this meant for those babies developing eczema or wheezing in later childhood.
That’s important – they didn’t look at the types of whole foods we recommend you introduce, but rather just infant cereal (which we don’t really recommend). This was presumably because the focus of the study was more on the outcome so a more neutral, easily measurable food was used to cut out the potential skewing that could be caused by the variable of the type of food introduced.
The study found that breastfeeding and family history of asthma both made a difference in terms of parents reporting eczema or wheezing.
That study found that in babies who were formula fed when solids were introduced, introduction to infant cereal at 4 months (rather than 6) was associated with a higher risk of eczema in later childhood (where there was no family history of asthma). Breastfeeding tended to be a protective factor as there was little evidence of an association between early introduction to infant cereal and eczema in childhood among the breastfed babies.
Interestingly, where a baby was breastfed at the time of solids introduction, where infant cereal was introduced at 4 months (rather than 6), the odds for the baby developing wheezing were higher – but generally, duration of exclusive breastfeeding did not generate hugely differing odds for wheezing in children.
Where the baby’s family had a history of asthma, this study found that the timing of introduction of solids did not have a noticeable impact on whether the baby went on, as a child, to develop asthma or wheezing – i.e., that family history of atopic dermatitis may represent a risk which cannot be shifted by timing of complementary foods being introduced. However, this study did not look at family history of eczema and some other atopic diseases which could be important.
Previous research
This study also looked at previous research done in this area (including a UK cohort study which found that children who were introduced to solids before 4 months had higher odds of developing eczema by age 5 compared to those introduced to solids after 4 months) and a Netherlands birth cohort study (which had found that where babies were introduced to solids after 7 months, their risk of developing atopic dermatitis, eczema and wheeze by age 2 was greater than those introduced to solids between 4-6 months). Another previous study had also found no correlation between the timing of introduction to solids and atopic dermatitis or asthma. However, this more recent study we are exploring now, noted that the important confounding variables of breastfeeding status, parental smoking, and so on, as well as short follow-up duration, were not taken into account.
What about breastfeeding?
Breastfeeding in particular played an important protective role in terms of a baby’s developing microbiota which develops rapidly during infancy and can resemble the adult microbiota when a baby is just one year old. Where a breastfed baby is introduced to solids slightly later and therefore continues to exclusively breastfeed, this could convey benefits to the baby’s microbiota (and therefore immune response) because of the way breastmilk supports a baby’s GI defence mechanisms and contains anti-inflammatory compounds.
Does this mean you should continue to exclusively breastfeed beyond 6 months and delay the introduction of solid foods to help support your baby’s developing microbiota? Well, as above, there is mixed evidence on delaying the introduction of solid foods until, say, 7 months and beyond, but in our view the importance of nutrients such as iron, zinc, and so on, whose stores in breastmilk deplete around 5-6 months, cannot be ignored – hence the sensible recommendations of several national health bodies that solids should be introduced at this point. We would of course encourage mothers to continue breastfeeding where possible and desirable at least until 12 months. The WHO recommends breastfeeding for at least the first 2 years of your baby’s life where this continues to be mutually desirable – as we recognise the demands of modern life, lack of support and work commitments mean this is not always possible. In any case, your baby should be receiving either breastmilk or formula (or a combination of both) until at least 12 months, in tandem with complementary solid foods from 6 months onwards.
Ok, so now what?
So, what’s the point in talking about this?
The study essentially corroborates the AAP, CPS and NHS guidelines that solids should not be introduced before 6 months (unless you receive specific medical advice to the contrary from a health professional you can trust) – and this is for babies who are at low risk for allergy.
If, however, your family has a history of allergy – meaning your baby could therefore be at high risk for allergy themselves – the recommendation may be different. We say this as the AAP and CPS both say that introducing solid foods, particularly some allergens, between 4-6 months for those high-risk babies, could be protective. In any case, if you have a family history of allergy or are otherwise concerned that your baby is high risk, please consult your allergist or other appropriate healthcare professional to seek advice from them.
Family history of asthma and whether or not a baby is breastfed both, respectively, have an impact on the timing of the introduction of solids and what this means for a baby developing eczema or wheezing. As above, however, family history of eczema was not explored by the study we cite, so this is something further to consider.
Ultimately, this study concluded that where there was no family history of asthma, introduction of solid foods (in this case, infant cereal) at 4 months rather than 6 months, was associated with a higher risk of eczema or wheezing in later childhood.
Hopefully this has helped you digest some of the recent (and the consistent) recommendation that solid foods should, generally speaking, not be introduced until around the 6-month mark.
Disclaimer
As with all of our musings and recommendations, we caveat the above by saying that if you are at all concerned, please seek medical advice. This blog post, and our other recommendations, are not substitutes for such medical advice.
research study: https://bmcpediatr.biomedcentral.com/articles/10.1186/s12887-023-04262-0