How Much Does Diet Matter When You’re Breastfeeding?

There are many diet demands placed on nursing mothers. Here’s what the evidence says.

Say you’ve lived through the nine months — really 10 — of pregnancy food restrictions. The baby is finally here. And, lucky you, breastfeeding seems to be working. Now you’re dying for a rare steak and a glass of pinot noir.

“Just remember,” trills the internet. “The baby eats what you eat!”

Soon after birth, mothers are forced back into a world of restrictions. Breastfeeding moms are told to forgo or limit alcohol, and consider timing their caffeine consumption to avoid coffee too close to nursing.

Then there are general diet rules: Breastfeeding moms should eat whole grains and good fats.. The site What to Expect suggests mothers should be cautious about eating non-organic foods and high-fat meat due to pesticides. Dr. Sears encourages mothers to eat fish for optimal brain development: “Four ounces of fish a day keeps central nervous system degeneration at bay.”

In the emotionally charged world of infant feeding, mothers often hear that “breast is best.” Over and over again. And with all this focus on the benefits of breast milk, it’s hard not to wonder if there are more gradations: Is some breast milk better than others? It would be a shame to put all that time and energy into nursing only to find out that the key to really reaping the benefits is to drink organic kale and chia seed smoothies every morning.

But is that right? Does the breastfeeding diet actually matter? Will your child do better in school — or avoid something scary like “central nervous system degeneration” — if you eat differently while nursing?

Short answer: No.

Longer answer: What you eat does affect your milk in the sense that, for example, if you eat more fat your milk will have a higher fat content. But there is no evidence that any of these differences have any long term consequences for your child. You might be surprised to learn that even the distinction between breast milk and formula is much, much smaller than often claimed. Small differences in the nutrient content of breast milk would, by extension, matter even less.