© 2014 Roy Benaroch, MD
Miranda wrote in with a topic suggestion—she wanted to know about homemade infant formula. She had noticed a lot of people suggesting it. What’s the deal?
Speaking about nutrition and human babies, it makes sense to start with this: human breast milk, from mom, is the best food for babies. But even that is an over-simplification. It turns out that in the modern world, human breast milk is often deficient in vitamin D, and maybe iron, too. I know I’m going to get some heat over this, but it’s true: even human breast milk isn’t “perfect.” It’s close, but if we’re going to be honest, even straight-up mom’s milk isn’t “ideal” for babies.
So what’s the best alternative? The contestants: human breast milk, which we’ll just call “human milk.” Commercial infant formula, which we’ll call “science milk.” This is the stuff that’s been studied for years, and is lab-designed to give babies the exact nutrition they need to thrive. Then there’s home-mixed infant formula, which we’ll call “homemade milk”, usually prepared based on an internet recipe. What kind of “grade” should we give our three competitors, based on an objective assessment of their composition?
The number one “ingredient”, so to speak, is water. Clean, pure, safe water. Human milk, fresh from the breast, is free of harmful contaminants and infectious germs. Science milk is made under sterile conditions, and the liquid versions are pasteurized—as long as they’re stored correctly, there’s essentially no risk of infections spreading. Homemade milk? Who knows. I doubt anyone at home is sterilizing all of their surfaces to the extent done in a commercial lab. And some of the homemade milk recipes call for unpasteurized, “raw” milk—which can be loaded with animal colon bacteria as has been linked to all sorts of colorful infections. Winners: human milk and science milk (tie); loser: homemade milk.
Then there’s protein. There’s too much protein of the wrong kind in most mammal milks (including cow and goat), so science milk relies on modified mammal milk or soy to get the right amounts of the right kind of proteins. The wrong proteins can cause intestinal and kidney damage. One homemade milk recipe I found used blenderized livers as a protein source, which is even more dangerous. Human milk, protein-wise, is perfect. Winner: human milk, with science milk a close second. Loser: homemade milk.
The carbohydrate in all mammal’s milks is mostly lactose. Goats, humans, cows—our milk is all lactose-based. Science formulas sometimes substitute other carbs, largely to take advantage of the fear of lactose intolerance (which doesn’t occur in human newborns.) There’s no known downside to this, though it’s kind of silly. Winner: tie! Lipids (fats) are pretty much the same across the board, or near-enough so.
Sodium: ordinary milk from other mammals (goats and cows and presumably kangaroos, though I honestly don’t know about them) has far, far too much sodium. To properly reduce this, homemade formulas have to dilute that out somehow. Winners: human and science formulas.
Other micronutrients: there are a lot of these, of course—iodine and vitamin C and vitamin D and iron. And these really are important. Iron deficiency in infancy can contribute to permanent cognitive problems. You really do want to make sure that Junior is getting all of these vitamins and minerals in the exact proportions needed. The micronutrient content of human milk has been extensively studied, and science formula does a great job in either copying that, or even improving on that (re: iron and vitamin D.) Winner, science formula, by a nose; human milk is a very close second. Homemade formula are based on dozens or maybe hundreds of recipes, and no one has systematically figured out which if any actually deliver the micronutrients that are needed.
Here’s a funny, true story from my residency: an 8 month old baby was admitted to the pediatric intensive care unit, near death. (Wait, it gets funnier.) He was very, very anemic—I remember noticing when drawing blood from his nearly lifeless body that the blood itself was kind of watery and runny. He also had neurologic problems and his vital organs had shut down. It turns out that his father was traveling hours a day, back and forth, to a farm to pick up fresh goat’s milk to feed him (because his parents had heard that goat’s milk was healthy!) Since goat’s milk is entirely deficient in one of the B vitamins (folate), the child’s blood marrow pretty much shut down. And there were a whole bunch of other health consequences related to other nutrient deficiencies and protein overload. After a few weeks in the ICU the baby survived. Isn’t that a funny story? No, of course it isn’t. It isn’t funny at all.
Ease of use and preparation: human milk wins, here, of course—though it has to be said, not always. Some women really do have a hard time nursing. It’s not always the easiest choice. Fortunately, we have another reasonably easy alternative: science milk. Mix the powder with water in the right proportion, and you’ve got pretty much exactly what your baby needs. The worst choice, here, would be homemade milk: it’s complicated and fiddly, has a lot of ingredients to get wrong, and it still may not even provide the nutrition your baby needs.
Homemade infant formula is a terrible idea. There is no way for parents to make something as pure and complete as either human milk or commercial infant formula (science milk.) There’s no evidence whatsoever that it even might be safer or better in any tangible way. This is one case where homemade is not the way to go. If you’re not breastfeeding, you should use commercial infant formula. Do not trust your baby’s health on your chemistry skills and recipes from the internet.