Scientists are trying to make human breast milk in a lab. Some say it’s a fruitless exercise

Biotech companies are racing to be the first to fully replicate human breast milk – using genetically modified yeast – in the hopes of upending the multibillion-dollar infant formula market.

Australian biotech company All G says it will soon file a patent for what it claims is the closest infant formula to human breast milk ever invented, while on Tuesday the CSIRO also announced its spin-out, Brisbane-based Eclipse Health, had millions of dollars in funding to develop yeast-grown lactoferrin – an anti-inflammatory protein found in breast milk.

Chief scientific officer Jared Raynes (left), head of nutrition Shae Rickards and chief executive Jan Pacas at the All G lab in Sydney. Credit: Janie Barrett

“This is the closest infant formula has ever come to the real thing,” said Jan Pacas, chief executive of All G. “We’ve moved beyond imitation into true replication.”

If it makes it through the approval processes, All G could compete with formula products, most of which are derived from cow-based milk products.

The company said its formulation produced five major human breast milk proteins through a process called precision fermentation, which uses genetically modified yeast in a vat in a method similar to beer brewing. It expects the product to be available on shelves by 2028.

But some industry experts say true replication is nearly impossible to achieve within the bounds of current science.

Professor Kevin Nicholas, who has been researching breast milk composition for more than 50 years, said human breast milk had evolved over millions of years into a product perfect for babies and their nutrition.

“Three, four or five proteins don’t make milk. The reality is that there are hundreds of components … it’s very, very complex. It’s got a lot of different components in it. And a few proteins don’t constitute breast milk, or any kind of milk,” Nicholas said.

Like with all new health products, there would be numerous hurdles to overcome before the new breast milk substitute is available to consumers, he said.

Nathan Hawkins and Jess Swatosch in the All G lab. Credit: Janie Barrett

“You have to prove your product is safe and … that it does have advantages,” Nicholas said. “There are a number of regulatory bodies to pass through and a number of steps. And often an end point is clinical trials.”

Associate Professor Wendy Ingman, who researches breast health at the University of Adelaide, said All G’s new product was an example of positive changes within the industry over recent years.

“It’s a step towards improving infant formula,” Ingman said. “It’s a cleaner way to make the proteins because they’re able to manufacture them to be more like the human proteins in breast milk.”

But Ingman said human breast milk remained a food source that specifically served babies’ nutrition.

“Human breast milk has got thousands of proteins and different types of carbohydrates and fats in it. It’s a very complex fluid. And while this is improving infant formula, I don’t think it’s going to be on par with the real thing,” she said.

For Pacas, All G isn’t trying to replace human milk or claiming it can directly replicate it – rather, it’s aiming to provide a breast milk substitute that is more nutritionally beneficial than current formulas.

“We’re focused on producing the protein mix,” said Jared Raynes, chief science officer at All G. “That’s only one portion, but an extremely important portion, of the formula.”

Pacas said All G’s new product shared between 70 and 80 per cent of natural breast milk’s composition when combined with essential human fats and carbohydrates.

“We’re not saying we’re identical to breast milk … [but] it’s still totally transformational to what you have out there today because [babies] are drinking basically cow milk, not human,” Pacas said.

Dominique Adamidis with children Charlie, 3, and Sal, 3 months. Credit: Wayne Taylor

“Breast milk is absolutely the best. But there are situations when you simply cannot [breastfeed]. You need to go to work, or babies are born prematurely and you don’t have breast milk at all.”

Melbourne mother Dominique Adamidis preferred breastfeeding for both of her children.

“I wanted to try and not use formula because there are benefits of breast milk that don’t exist in formula … so breast milk was always going to be my first choice,” she said.

But Adamidis is glad substitutes are an option for those who are unable to breastfeed. She said improving the nutritional value of formulas would be greatly beneficial for such parents.

“Obviously, there’s a myriad of reasons that … people won’t be able to breastfeed, and formula is fantastic [in those instances].

“I think there should be no shame around formula feeding, and there should be no concern that your baby’s nutritional needs are being met when you’re using formula.”

Nicholas said the industry should prioritise encouraging women to donate breast milk.

“We have to rely on formula and fortifiers that are largely produced from cow milk … and there’s no doubt that it’s not as efficacious as breast milk.

“We’ve got to do a lot of work globally with milk banks to get more donated human milk onto the wards and into hospitals and to babies that actually need it.”

Adamidis donated breast milk when she had an oversupply while her first child was young.

“It’s a great thing if that’s what people want to do … I had excess [milk], my baby stopped taking a bottle, so I had no real use for it myself,” she said. “It didn’t feel like I was going out of my way to do something special.”

Enjoyed Examine, our free weekly newsletter covering science with a sceptical, evidence-based eye? Sign up to get the whole newsletter in your inbox.