When it comes to babies, parents probably encounter the most advice about when and how to introduce solid foods. After weeks and weeks of sleep deprivation, the thought inevitably arises: Could putting a little cereal in the baby’s bottle help the baby to please, please, please sleep just a little longer?
Unfortunately, research looking at the effectiveness of this approach does not demonstrate any impact on onset, duration or quality of a baby’s sleep. However, there is emerging, good-quality evidence that suggests peril in introducing solids too soon — before four months. Early introduction of solids in formula-fed babies has been associated with a six-fold increase in the likelihood of obesity at age 3. Additionally, overeager introduction of solids has been associated with an increased likelihood of asthma, eczema and allergic rhinitis later in life.
In light of these associations, it was theorized that delaying the introduction of solids might reduce the risk of problems down the road; however, the evidence is to the contrary. It seems that waiting beyond six months is also associated with an increased risk of asthma, allergy and eczema.
The prevailing theory now suggests that exposure of the baby’s immune system to the foreign substances during the sweet spot between four and six months may allow a certain “immune tolerance.”
But advice isn’t limited to when to introduce solids. There’s a slew of strong opinions about the type and order of foods a baby can eat — rice cereal, then green veggies, then yellow veggies, then fruits and so on. These algorithms may make things easier to follow and remember, but they are based on anecdote and opinion more than any demonstrated evidence.
Although the traditional order of introduction may not make much difference, there may actually be something to the types of foods that are introduced during the crucial window. One study associates a higher sensitization to inhaled allergens when potatoes and fish are delayed and to other food allergens when eggs, oats and wheat are delayed beyond six months. Multiple studies find an increased sensitivity to gluten later in life when exposure to wheat occurs outside the four-to-six-month window. Another departure from conventional beliefs relates to introduction of meats. It is now believed that meats are possibly the best food to introduce after grains, due to their excellent caloric density, and content of iron and zinc. So throw that prime rib in the blender — seriously.
It is important to note that while all of these bits of new evidence are compelling, as usual, more evidence is needed. Although some of the studies measure clinical symptoms diagnosed by a medical professional, many of these studies look at sensitization by searching for antibodies found in the blood. However, the presence of those antibodies doesn’t always correlate to clinically significant symptoms. Another source of potential bias that is not clear is related to something called reverse causality. This involves an outcome influencing an exposure. For example, the parent of a baby who was showing evidence of eczema at two months of age might be concerned and delay exposure to solids, leading to the misinterpretation that the delay is what caused the eczema, rather than the eczema causing the delay. There are plenty of little details to work out before we’re absolutely sure.
For now, here are the main rules when it comes to introduction of solids:
No honey before 12 months. Botulism spores are able to cross the gut barrier before that age, and botulism is bad for babies.
No cow’s milk from a jug before 12 months. The unmodified proteins are too rough on the gut, and microscopic bleeding can lead to anemia. This goes for goat’s milk as well, which also lacks folate.
Your baby needs to have the oral motor skills and strength sufficient to actually eat from a spoon — this is often around four months for most babies.
Always be careful about choking hazards. Your baby may not get hives from a pickle, but they sure could choke on one — choking is something to be paranoid about.
Exposure to foods after four months may not cause allergies, but it may reveal them. Watch your timing and give every food two to three tries before introducing the next new food.
There really is no big hurry to cram three big meals a day in your baby — feeding is more about social, motor and maybe immunity at this age. The bulk of nutrition for your four-to-nine-month-old still will come f rom what they drink. In this regard, breast milk really is the ideal drink, if there is enough of it, and you supplement with vitamin D. Fortunately for those unable to breast feed, or needing to supplement, formulas are better than ever and an excellent source of nutrition.
If there is any family history of food sensitivities, check with your allergist or pediatrician before introduction of the problematic food. In fact, even if you don’t have a family history of food sensitivities, be sure to discuss the introduction of solids with your baby’s care provider. Opinions on this topic vary, and are always changing.
Matt Thompson is a pediatrician with Spokane’s Kids Clinic.
