Tag Archives: Solids

Introducing Solids and Baby Sleep: Yep, Early Solids Improve Baby Sleep After All

Don’t give your baby solids until 6 months of age. This is the unambiguous advice of the world’s most highly regard medical organizations, including the American Academy of Pediatrics, the UK’s National Health Service, and the World Health Organization.

Ignore the “mistaken” belief that introducing solids earlier will help your baby sleep better. Early solids could have the opposite effect, worsening your baby’s sleep, according to popular parenting sites like Kelly Mom and the Baby Sleep Site.

Or so we have been told.

It turns out that the claim that solids don’t help baby sleep was based upon the shoddiest of studies–small, non-randomized, poorly controlled–like this one, which simply looked at whether babies were eating solids and how well they slept.

(To be clear–I am not trying to knock this research as research. Small exploratory studies can be very useful for hypothesis generation and deciding on which large studies to run, but the stuff of sound public health pronouncements they are not.)

Now, we finally have much better data, from a randomized trial of over a thousand babies. And surprise, surprise, your mum (or in my case, my mother in law) was right all along: Introducing solids early, at around 3 to 4 months, does improve babies’ sleep. Not just then, but for their entire first year.

The Details

The new study is a secondary analysis of the UK-based Enquiring About Tolerance (EAT) randomized clinical trial, a trial whose main goal was to assess whether early solids lowered the risk of food allergy.

In the trial, researchers randomly assigned 1,303 exclusively breastfed infants to either begin solids at three months (the experimental group) or at around 6 months of age (the control group).

Parents in the experimental group began feeding their babies solids at around 3 months of age, with specific instructions to expose them to six common food allergens (eggs, peanuts, white fish, cow’s milk, wheat, and sesame seeds).

The randomization was highly successful. Nearly all babies in the early introduction group began taking in solids by 4 months of age, whereas almost none of the control babies started solids until after 5 months of age. Notably, nearly all these babies continued to be breastfed, almost none received formula.

Although the EAT trial’s original purpose was to determine if early solids would help prevent food allergies, the study also carefully assessed the babies sleep. Each month, parents reported how long their babies slept at night, how often they awoke at night, and if they felt their babies had mild or severe sleep problems. They also described where their baby slept and how they put their babies to sleep.

Thus, this study represents the largest, carefully constructed randomized trial of how solids affect infant sleep ever performed.

So what did they find?

Babies who received solids early, starting around 3 to 4 months, slept better than controls. They slept a tiny bit longer each night during their first year of life (an average of 6-7 minutes overall, with the biggest difference–17 minutes longer each night–seen at 6 months of age). They were also about 10% less likely to wake up at night. So good, but not really much to write home about.

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Where early solids packed the biggest punch, however, was in preventing sleep problems. While only a small percentage of babies had sleep problems (fewer than 5% overall), control babies were much more likely to be problematic sleepers.

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As shown in the graph below, severe sleep peaked at around 9 months, and then dropped off sharply at a year (good news for many a bleary-eyed sleep beleaguered parent).

Most strikingly, parents of early introduction babies were far less likely to say their babies had mild or severe sleep problems throughout their first year of life–long after the controls were also taking in solids. It appears that early solids helped babies consolidate their nighttime sleep earlier, and this benefit persists throughout infancy.

This latter point was surprising to me, but appears well supported. In fact, the more solids experimental babies ate earlier, the better they slept. (This was a follow-on analysis, and not randomized, but it does lend further support to their main findings.)

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The Bottom Line

So, does this study mean we should all give our babies solids early to help them–and us, let’s not forget us!–sleep better?

By itself, probably not. The effects on sleep are pretty small, overall, (6-7 minutes extra sleep a night; about one less night awakening a week). And before we run completely in the opposite direction and overinterpret these findings, I would really love to see at least one other randomized trial examine the same question.

And we need to note that the babies who slept best in this study (as we already know) were not co-sleeping, slept in their own rooms, and went to sleep by themselves, without parental assistance. These practices had a much bigger impact than solids on baby sleep and remain the foundation for helping your baby sleep well.

That said, let’s step back a second and consider the larger context. Many studies now suggest early solids lower the risk of allergies. This is why many medical organizations that focus specifically on allergies recommend starting solids earlier (4-6 months) than their umbrella counterparts (6 months)–creating schizophrenic, headache-inducing advice for well-meaning parents.

For me personally, speaking as a parent, I would look at these findings and choose to start giving my baby solids at around 4 months of age.

(Introducing peanuts early lowers the risk of peanut allergies. Although the EAT trial did not actually show significantly lower risk of food allergies, there was a trend in that direction.)

As I have written about earlier, the recommendation to breastfeed exclusively for 6 months really only makes sense for women living in developing countries, where access to clean water and safe food sources can be limited. There are no demonstrated benefits for women living in developed countries like the US and the UK. It’s past time for medical organizations to reconsider this misguided blanket advice.


How much iron does my baby need?

Too little iron in infancy can cause irreversible cognitive deficits. And iron deficiency can have no symptoms. It’s scary.

Yet the advice parents get on meeting your baby’s iron needs is complex, conflicting, and incredibly confusing.

Continue reading How much iron does my baby need?

The NEJM Peanut Study: Is It Better to Introduce Allergenic Foods Early?

By now, you’ve probably heard about the recent study, which showed that early consumption of peanuts lowers the risk of peanut allergy by as much as 86%.

 The study, led by Gideon Lack of King’s College, London, and published in the New England Journal of Medicine in February, is the first randomized clinical trial conducted on preventing peanut allergy in children. Widely hailed as a game changer, the study’s findings are already affecting the advice given to parents.

Just last week my friend’s pediatrician counseled her to “stir a little peanut butter” into her 6-month-old’s rice cereal. She barely managed to avoid gaping at him in astonishment. Just two years earlier, with her first child, he had told her to avoid introducing peanuts for the first year.

After decades of conflicting advice and vague admonitions, parents may wonder whether such a dramatic change is actually warranted. Is the evidence any better now than it was ten years ago? And if the guidelines were so mistaken before, why have confidence in them now?

And, perhaps the biggest outstanding question of all: what, if anything, does this study mean for when to introduce other highly allergenic foods, like fish, tree nuts, or eggs?

Continue reading The NEJM Peanut Study: Is It Better to Introduce Allergenic Foods Early?

Introducing Solids: Is It Best to Wait Until 6 Months?

In 2005, the American Academy of Pediatrics (AAP) changed their recommendations from gradually introducing solids between 4 and 6 months of age to exclusively breastfeeding for “about the first 6 months of life. For the first 6 months “your baby”, they assert, “needs no additional foods (except Vitamin D) or fluids unless medically indicated.”

My daughter at 9 months, eating peas and Cheerios

You might think that these recommendations were updated because of a new evidence showing substantial benefits for the baby of delaying the introduction of solids.

But, nope, this is not the case. Instead, these changes were motivated by studies showing an absence of harm to the baby and some minor potential benefits for the mother.

The World Health Organization was the first major medical organizations to recommend exclusive breastfeeding for 6 months, for reasons they outline in a 2002 research review (updated in 2007):

  1. No evidence exclusive breastfeeding for 6 months results in poor growth
  2. No apparent increase in the risk of allergies*
  3. A longer period of lactation-induced infertility, about an extra month on average
  4. Greater postpartum weight loss between 4-6 months, about a pound on average
  5. Lower risk of illness for the first six months, and possibly throughout the first year

* (Since this review was published, new evidence suggests delaying solids until 6 months may increase the risk of food allergies. More on this complex topic below.)

When weighing the pros and cons of exclusive breastfeeding for 6 months, the social and environmental context matters. The WHO crafted its guidelines to maximize health outcomes in both developing and developed nations. But benefits that have a large public health impact in the developing world, where access to basic medical care, birth control, clean water, and nutritious food is limited and inconsistent, can have little or no impact in the developed world.

Benefits of Exclusive Breastfeeding for Six Months

For mothers living in the developed world, the benefits of exclusive breastfeeding for 6 months are small, arguably negligible.

We have been blessed with access to birth control, so lactation-induced infertility is not a critical means of pregnancy prevention and birth spacing.

And, when it comes to weight loss, although almost every mother I know would gladly shed an extra pound or 2 of baby weight, the benefit is really small, just an extra a pound on average. Surely there are other activities that do not require 8-hours a day, round-the-clock efforts that would be just as effective forms of weight loss.

Certainly neither of these two benefits warrant the stress placed on introducing solids “at the right time.”

Of the reasons given by the WHO, the only truly persuasive one is a reduced risk of illness for the baby during its first 6 to 12 months of life. Here again, though, there are important differences between the developing and the developed world.

In the developing world, exclusive breastfeeding for 6 months is literally life saving. Within the 42 nations with the highest child mortality rates, widespread adoption of exclusive breastfeeding for 6 months would prevent an estimated 13% of the deaths of children under the age of 5. This is a larger percentage than would be saved with improved access to antimalarial medication or antibiotics.

Within the developed world, the picture is more nuanced. Here, completely weaning from breast milk before 6 months, or introducing solids before 4 months, or introducing formula before 6 months substantially increases the risk ear infections, diarrhea, pneumonia, and bronchitis.

But gradually introducing solids between 4 to 6 months while continuing to breastfeed does not. Studies that compare the outcomes of infants who were exclusively breastfed until 6 months (EBF or exclusively breastfed) with those who were exclusively breastfed for at least 4 months and then partially breastfed thereafter (MBF or mostly breastfed) find that 6 months of exclusive breastfeeding neither harms nor benefits growth and development.

The only apparent benefit of delaying until 6 months was a 25-50% lower risk of diarrhea in the first year of life. The effects on ear infections, pneumonia, and bronchitis were unclear: A couple of observational studies found a lower risk, but the majority of studies, including the only two randomized controlled trials, found no effect. And longitudinal study conducted in Belarus found no differences in weight, height, BMI, asthma, allergies, or other illnesses by age 6.

“Exclusive breastfeeding for six months does not seem to confer any long-term (at least to early school age) protection against obesity or allergic disease, nor any benefits in cognitive ability or behaviour, compared with exclusive breastfeeding for three to four months with continued partial breastfeeding to six months.”  – Kramer & Kakuma, 2012

Costs of Exclusive Breastfeeding

Lower Iron Status. EBF infants tend to have lower iron levels than mixed fed or formula-fed infants. Two randomized controlled trials, one conducted in Honduras and the other in Iceland, found significantly higher iron levels among MBF than EBF infants. Reassuringly, at 6 months of age, iron levels in both groups remained within the normal range, and the EBF infants were not more likely to be iron deficient or to develop anemia.

Still, iron needs rise sharply in the second half of the first year when newborn iron stores have been depleted, and lower iron status in the first six months could place EBF babies at higher risk of iron deficiency as they age. This is why the CDC considers “breastfed babies who after age 6 months are not being given plain, iron-fortified cereals or another good source of iron from other foods” to be at high risk for iron deficiency and anemia.

Increased Risk of Food Allergies. On this point, the advice given to parents has seesawed from it is best to delay solid foods, especially highly allergenic ones, to it is best to introduce these foods early, between 4 to 6 months. This is because the evidence behind the advice is of poor quality and inconsistent. A handful of observational studies find that early introduction increases the risk of allergies. A comparable number find that late introduction increases the risk. And not all of the studies find when solids are introduced matters at all.

Some researchers to speculate that there is something of a sweet spot in infancy, between 4-6 months of age, when introducing solids lowers the risk of allergies. This protective effect may be strongest for peanuts and cooked whole eggs. But until proper clinical trials have been done, it seems wise not to make too much of these findings. (UPDATE: A randomized controlled trial has now shown that introducing peanuts before 1 year of age lowers the risk of a peanut allergy substantially. More on this study here.)

The AAP no longer recommends waiting to introduce solids until 6 months or later to reduce the risk of allergies, and instead advises waiting until at least 4 months. And of course, this statement on solids and food allergies conflicts with guidance the AAP gives elsewhere to exclusively breastfeed for 6 months.


Like so many parenting decisions, the actual evidence suggests that we can all relax a bit. For those of us lucky enough to live in the developed world, introducing a small amount of solids between 4 to 6 months is unlikely to harm our babies, and equally unlikely to benefit them.

That said, when giving your baby solids before 6 months, it makes sense to provide small amounts. The immune benefits of breast milk are dose-dependent: the more milk the baby takes in, the greater the protection from illness. This is why solids during the first year should not be used to replace but to supplement breastfeeding. And when introducing solids, especially to exclusively breastfed babies, it makes sense to emphasize iron rich foods like broccoli, meat, eggs, fish, and fortified cereals.

Here is most sensible statement I found on the 6-month rule, from a review article in The BMJ, the flagship journal of the British Medical Association:

“From a biological perspective, the point when breast milk ceases to be an adequate sole source of nutrition would not be expected to be fixed, but to vary according to the infant’s size, activity, growth rate, and sex, and the quality and volume of the breast milk supply.”  – Fewtrell, Booth, & Lucas, 2010

When did you first introduce solids? Did the risk of allergies or infections play a role in your decision?