Nestlé has defended its decision to change the recipe for its popular SMA infant formula after worried parents complained on social media that their babies had become sick.
The company reformulated its SMA milk range as SMA Pro in January but has come under fire after a 20-year-old mother from Cumbria launched a campaign calling for the product to be banned.
The SMA formula was relaunched as SMA Pro in January with a slightly reduced pack size, and now includes "non-digestible fibres" and omega-3 derived from fish oil.
Nestlé said the changes brought the product in line with other brands.
Catt Taylor, who set up a petition that has received over 12,000 signatures since it was launched last Wednesday, said the ingredients of the formula were changed "without any warning".
Her 10-month-old child Alayah "quickly started to become ill" after being fed it, she said, and became hospitalised with sickness, diarrhoea, and a high temperature.
"She had a swelled tummy and wasn't eating" the petition says. Taylor told BuzzFeed News: "She was just vomiting constantly."
The petition has sparked a debate on parenting forums including Netmums with some defending the formula and others using the petition, and Twitter, to express similar concerns, with some arguing Nestlé should have made the recipe change clearer on pack.
Nestlé confirmed that it had received calls from a number of parents wanting to discuss their children having had "softer" stools since starting the new formula, but told BuzzFeed News "all of the evidence shows it is a safe product".
Taylor told BuzzFeed News doctors were unable to say what was wrong with Alayah, initially believing it could be a virus or gastroenteritis, though tests came back negative.
Taylor said doctors had asked her whether she'd changed Alayah's formula in a bid to find out whether she could be reacting badly to a change in diet. Taylor, who hadn't noticed the recipe change and had always fed her the SMA brand, said no.
It was only last week that she noticed the change of ingredients on the back of the tin.
Taylor said her GP said Alayah appeared to have been experiencing a bad reaction to the formula, with sickness and diarrhoea causing dehydration, and advised to stop feeding it to her.
She said a health visitor had also told her that another parent had reported similar problems with the formula acting "like a laxative".
"When I found out I felt absolutely awful," Taylor said. "I'm heartbroken. Because she was not eating, I was giving her more."
When she stopped feeding Alayah the product she saw a change overnight, she said.
Other parents have been commenting on the petition page and social media about the product.
Nestlé said its product now contains ingredients called galacto- and fructo-oligosaccharides that "will help to produce a softer stool and which may help babies to pass stools more easily".
Aside from those, a spokesman said, "there have been no other new ingredients that were not there previously" – although the company's website appears to show that the omega-3 and -6 is now derived from fish oil in some varieties of SMA Pro, meaning they are no longer vegetarian.
The website recommends "you should keep your baby on the formula for at least 5 days to give them time to settle".
The galacto- and fructo-oligosaccharides, which have been used by other formula companies across Europe "for several years", met strict legislation regarding safety and composition and are also present in other brands, the spokesman said.
Customer care representatives have also established that despite changes in bowel movements, none of the cases brought up by concerned parents thus far have actually been diarrhoea, he said. Also, no healthcare professional had "raised any serious concerns" about the safety of the product.
"It is worth noting that even when we change our packaging only," he said, "we get calls from parents who believe that our 'new' formula has made their baby ill, when the formula itself is unchanged. In light of this, the amount of calls we got was around what we would expect.
"At SMA Nutrition, quality and safety are our highest priorities. ... There are tens of thousands of UK babies thriving on SMA Pro formulas, and we would like to reassure parents and carers of babies over the safety."
He said: "It is important to know that the new range has undergone several years of clinical testing before it went on sale. All of these studies showed that babies tolerate the new formula very well.
"We recognise that although the vast majority of babies will transition to a new formula very well, some may take some time to settle. This is perfectly normal."
Many babies display gastrointestinal symptoms such as constipation, diarrhoea, and vomiting during their first few months anyway, the spokesman said.
Nestlé was "very concerned to read Ms Taylor's claims" and has contacted her to establish the details of the complaint, the spokesman said. Taylor, however, told BuzzFeed News she was unwilling to allow the company to "scrutinise" her daughter's health.
Aisling Pigott, a spokeswoman for the British Dietetic Association, said it was "absolutely" possible for babies to react unfavourably to diet changes but an allergic reaction was unlikely because the differences between the makeup of brands was minimal.
"I do strongly believe that 'mothers know best' and if this mother feels this is the case for her child, then her wishes need to be respected," Pigott said. "It is, however, difficult to pin down these things at that age."
Pigott said she wanted parents to feel reassured that formula companies made best use of the evidence available to them but said that if a child was not tolerating feeding, parents should seek support from health professionals.
Nestlé told BuzzFeed News: "The safety of our products is non-negotiable and all of the evidence shows that SMA Pro is a safe product."
The UK's Food Standards Authority said it had received no complaints about the product. Consumers with concerns were advised to call its careline on 0800 081 8180.