Diet and nutrition in the first year – what makes the real difference for current and future health?
Paediatrician and epidemiologist Professor Charlotte Wright shares a blog for the Annual Conference 2017 to discuss the latest research around infant diet and its impact on short and long term health, including exploring topical issues such as vitamin D supplementation and baby led weaning. In this Q&A, she shares insight from research into the appropriate age for a healthy child to start solid foods.
What does the evidence say about when a healthy child should start solid foods?
In 2003, after a lengthy investigation, the World Health Organisation updated their recommended age for when a healthy child should start solids, from four months to six months. Since then there’s been a lot more research and evidence gathered, and although some individuals have questioned the recommendation, my view is that all the research has pointed to the correctness of the WHO judgement.
Back in 2003 I personally believed that babies were introduced to food between three and six months because that was the natural time to start, rather than because it was a cultural expectation. I’ve since learned better and changed my view; with this advice, parents are starting solids later with no ill effect – and with all the benefits of breastfeeding for longer.
The world over, parents view the starting of solids as evidence of their child maturing, developing, moving on, and because of this are tempted to start them early. It is really important to resist this assumption, the danger being that introducing solids early will reduce the child’s intake of breastmilk, which is really all they need for the first six months. Introducing anything else before this age increases the child’s risk of infection, with a number of UK cohort studies showing that exclusively breastfed infants are healthier than partially or non-breastfed babies.
What about children who are formula fed?
I’ve personally been involved in UK studies where even in formula feeding children, starting solids very early (before four months) increased the risk of health problems such as diarrhoea, so the WHO recommendation applies to all babies.
Has practice changed since the 2003 recommendation?
Hugely. In 2003 around 95% of babies had started solids by four months (as recommended at the time). It was completely normalised. By 2010, that proportion dropped to around 30%, with the majority of parents starting their child on solids between five and six months.
Have there been any challenges to the recommendation?
There is a push, particularly from the formula industry, for the recommendation to be changed from six months back to four-six months. We’ve reviewed all of the challenges and found no evidence for them. One argument is that waiting till six months to introduce solids runs the risk of children not having enough to eat and particularly not enough iron, but it actually has been found to have no increased risk of adverse weight gain or iron deficiency anaemia.
Another claim against the recommendation comes from psychologists, who argue that there’s a “critical” period for the introduction of tastes and texture, and missing this early window will lead to children being fussy eaters. This argument was already being questioned before 2003, and we’ve still found no strong evidence for this. Any research that is cited to support the claim is observational, and is actually reflecting reverse causation. In other words, the children studied had started solids later because they were fussy eaters; they didn’t become fussy because they started late.
Another massive claim: allergy. We used to advise parents to avoid allergens in the first year of their child’s life so as to reduce the likelihood of developing allergies. Now Allergists have gone completely the other way, suggesting that introducing allergens with other solids i.e. around six months, increases the child’s tolerance. But the formula milk industry are using this research to argue that allergens (and other solids) should be introduced before six months to increase a child’s tolerance even further. Again, there is no evidence for this, with a recent review of evidence from the Scientific Advisory Committee on Nutrition (SACN) and the Committee on Toxicity reinforcing recommendations to exclusively breastfeed for six months and only introduce solids (including allergens) around six months. Rather than pushing for an earlier introduction of solids, to the potential detriment of continued breastfeeding, we need to focus on the positive message that introducing peanut and hen’s egg at six months does not cause allergy, and in fact, delaying introduction until twelve months of age can increase the risk of allergy.
So, in summary, concerns about the risks and impracticality of deferring solids till the age of six months have proved to be unfounded. There is no rush to start solids and every reason to avoid them till six months as this maximises children’s exposure to breastmilk.