How your breastfeeding diet affects your baby

I was lucky that my son was a dream baby to breastfeed, with a great latch and voracious appetite from the get-go. But there were times when he spat up a lot more than what I thought was normal. My aunt suggested eliminating onions from my diet, as her kids were sensitive to them as babies; when I did, his spitting up stopped immediately.

I thought I’d found an obvious resolution. But according to the latest research on the connection between a breastfeeding mom’s diet and her baby’s fussiness or discomfort, it may have been a fluke. While in the past it was widely believed that your diet could cause your baby to throw up, have coloured stool or develop colic, today’s experts think a correlation is actually quite unusual.

Jack Newman, a renowned Canadian breastfeeding author and expert who has helped about 40,000 mothers and babies at his clinics over the years, says that an exclusively breastfed baby reacting to something in the mother’s diet is too often diagnosed when it isn’t the problem. “The notion that it is extremely frequent is all over the Internet and discussed in doctors’ offices, but babies cry for many reasons—far more commonly because of breastfeeding technique than sensitivities to what a mother eats,” he explains. “If your baby is fussy, your first step is to see someone who is experienced with helping mothers breastfeed and who observes the baby at the breast.”

If it’s been determined that the baby has a good latch and is breastfeeding well, and the problem continues, it’s time to look for other culprits.

There are instances, though not as common as once thought, when nursing babies do react to something mom has eaten and she may need to eliminate it. “I’ve known many moms who saw a connection,” said Kristen Yarker, a registered dietitian in Victoria. “The specific foods are unique to each baby, but as an example, some suggest that removing dairy from a mom’s diet can provide relief for a small portion of babies who have colic.” Having said that, Yarker explains that lactose intolerance is extremely rare for babies. “Breastmilk is naturally very high in lactose—it is one of its major energy sources, regardless of whether or not a mother drinks dairy,” Yarker explains. “Lactose intolerance usually develops after the age when, evolutionarily, human beings wean from breast milk.”

So if you’ve ruled out everything else that may be causing your baby to be fussy or spit up, it can be worth a try to eliminate and then reintroduce a food to see if it has any effect. Here’s how: Keep a food journal and take note of any patterns between what you’re eating and your baby’s reaction, which could show up immediately or between 48 to 72 hours after exposure. If you suspect a food, remove it from your diet completely for a good two weeks. If there’s no change, go back to eating that food again. If you see an improvement during the time you eliminated the food, do a little test by trying that food again and seeing if your baby’s symptoms return. If they do, you have a solution: Stop eating the offender.

“If it was a significant part of your diet, be sure to find alternatives to provide the nutrients you’re missing,” says Yarker. For example, if you cut out dairy, look to things like almonds, calcium-set tofu and green leafy vegetables like kale to ensure you’re getting enough calcium. (Always check with your doctor before eliminating or adding new foods.)

So could the onions I was eating really have been bothering my little one’s tummy? Science may say no, but my gut says yes—and so did my son’s. As parents, sometimes that’s all we have to go on.

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