Three years ago, after giving birth to her daughter, Nancy Noe had to accept the disappointing fact that she wasn’t producing enough breast milk to feed her baby. After trying everything—like frequent pumping and help from a lactation consultant—she did what she considered the next best thing: she went in search of the most organic baby formula she could find. “Reading the ingredients on the commercial formulas hardly made me feel any better,” Noe said recently. “I had no idea what any of this stuff was. I wanted another option.”

First, she considered using donated breast milk from a milk bank near her home in Manhattan Beach, California, but that didn’t appeal to her. She couldn’t be sure the donors ate a healthy diet, and some of the banks pasteurized the milk—a process she believed to kill the healthy microbes.

Then that she came across a recipe for a make-at-home formula created by the Weston A. Price Foundation (WAPF), whose stated mission is to restore nutrient-dense foods to the American diet. The formula is made using raw, or unpasteurized, cow’s milk and 13 additional ingredients—like homemade whey, lactose, gelatin, and healthy oils—designed to mimic the fat and nutrients in human breast milk.

Nancy was nervous to feed raw milk to her 7-week-old baby, and it initially didn’t go well. Her daughter experienced cheese-like vomiting, strange colored stool, and a lot of upset. “At first I thought, ‘What am I doing?’ ” Noe said. “But after two weeks, she began to thrive. She grew well, slept well, and loved her bottle. She’s now a very healthy 3-year-old.”

But the idea of a do-it-yourself formula—especially one made with raw milk— unsurprisingly has very vocal opponents. Unpasteurized milk can carry life-threatening bacteria like listeria, E. coli, and salmonella, which is why its sale is illegal in 10 states and heavily regulated in many others. According to the Centers for Disease Control and Prevention, 148 outbreaks due to consumption of raw milk or raw milk products were reported between 1998 and 2011, resulting in 2,384 illnesses, 284 hospitalizations and two deaths.

“The idea that you would feed raw milk to an infant is completely insane,” says Katherine Lilleskov, a Brooklyn-based lactation consultant and RN. “With their weakened immune systems, infants are particularly vulnerable to harmful bacteria. It’s our job to keep our babies away from that stuff, not willingly feed it to them.

Noe, however, is just one of the many voices extolling the virtues of the controversial homemade formula through a WAPF list serve. Here, new parents come to ask advice on dealing with common reactions to the formula (frequent, rubbery vomit), discuss tweaks to the formula for fussy or finicky babies (less nutritional yeast; remove the cod liver oil), and offer general support to each other.

The WAPF formula was first developed nearly 20 years ago by Sally Fallon Morell, the foundation’s founding president, and nutritionist Mary Enig, early advocates for whole foods. Since then, Fallon estimates, nearly 20,000 families have used her recipe to feed their babies, and the number of parents experimenting with the formula doesn’t seem to show signs of abating. Fallon argues that the formula provides immune-stimulating, health-promoting, and antimicrobial components very similar to human breast milk, and hears often from parents happy to have found an alternative to commercial formula.

“Why do we think the logical substitute for breast milk is something processed in a factory?” Fallon said. “The logical substitute is raw milk from another species—namely, healthy, grass-fed cows.” The raw milk, she says, bestows many health benefits like resistance to disease and good growth and development, and can even positively impact behavior. (For children who can’t tolerate cow’s milk, the foundation also provides a recipe made with raw goat’s milk, and one with liver broth.)

Don’t expect your pediatrician to support the idea. In December 2013, the American Academy of Pediatrics issued a statement advising parents against feeding raw milk to infants and children. Similar warnings have been issued by the CDC and FDA.

Among other things, medical professionals also worry about the possible harmful effects of improperly mixing the ingredients. Instructions on the WAPF website recommend making the formula fresh every day—a process that takes about 20 minutes. “That’s a lot of opportunities for exhausted parents to make a mistake,” said Dr. Sarah Keim, a scientist at Nationwide Children’s Hospital in Columbus, OH and lead researcher on these recent and disturbing studies of online breast milk sales. “You’re dealing with precise measurements, and heating some of the ingredients. A mistake could screw up the proportions, and alter the nutrient composition in a way that’s dangerous for a baby.”

Many parents who choose this option are well-aware that it isn’t supported by the medical community. Fallon admits to advising parents not to tell their pediatrician they’re using the formula. “They’re going to tell you it’s a terrible idea,” she said. “So my advice: don’t tell them. Put it in a Similac bottle if you have to.”

Given the potential dangers inherent in this choice why, then, are parents opting for it? They say the benefits they’ve observed in their children—and the desire to feed their baby a formula derived of whole, rather than processed, foods—outweigh any perceived risks.

Joe and Traci Auerbach of Columbus, Ohio have been feeding their daughter Cora the goat’s milk formula for more than a year. “You have to be careful about this, just as you’re careful about everything you do with parenting,” Joe said. “When I first started making it, I was terrified of getting something wrong. And then I got the hang of it.” And concerns that raw milk can be dangerous? “Be smart about it. Know your source,” he said, echoing a sentiment expressed by many advocates of raw milk. For him, this meant visiting a local farm to inspect the goats, ensuring that the milk was being produced under safe and sanitary conditions.

“Yes, seeing where the milk is made might help,” said Lilleskov. “But that certainly doesn’t negate the risks. And the thing with this is that it’s going to go well until it doesn’t. And if it doesn’t, it could be catastrophic.”

Aimee Molloy is a Brooklyn-based writer and the author of However Long the Night.

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