News

Botulism and bacterial toxins: The latest in infant formula recalls

Recalls of ByHeart and Nestlé infant formula products over concerns of botulism and bacterial toxins have put food safety back in the spotlight.

While the two recalls stem from different causes, both underline the risks associated with microbial contamination in powdered products and the role of preventative controls across sourcing, processing, and distribution.

ByHealth: Botulism in infant formula may be rare, but it poses a serious risk

In November 2025, ByHeart voluntarily recalled all infant formula products across the US within its Whole Nutrition range, after public health authorities linked a multi-state infant botulism outbreak to the product, according to the US Centers for Disease Control and Prevention (CDC).

The CDC said exposure to ByHeart’s Whole Nutrition powdered infant formula was associated with 51 suspected or confirmed cases of infant botulism across 19 states. All infants were hospitalised and treated, and as of January 2026, no deaths have been reported.

What is infant botulism?

Infant botulism is a neurological condition caused by the ingestion of Clostridium botulinum spores. Because the infant gut is still developing, spores can germinate and produce botulinum toxin in vivo, meaning the toxin is generated inside the body, rather than pre-formed in food. Symptoms may take days or weeks after ingestion to appear and range from constipation and poor feeding to muscle weakness and respiratory distress.

Unlike many foodborne illnesses, infant botulism is not typically linked to improper preparation or handling by caregivers. Instead, it is associated with resilient bacterial spores that can survive throughout the supply chain, from ingredient handling to packaging.

ByHeart’s investigation continues while production pauses

In a statement shared with Ingredients Network, a spokesperson for ByHeart said: “The root cause investigation remains ongoing and includes a rigorous audit of every step of our supply chain.”

The spokesperson said the company continued to share findings with the Food and Drug Administration (FDA) and was “working closely with regulators to identify the source of contamination”.

ByHeart has paused production and is undertaking additional testing “across ingredients, manufacturing processes, and handling procedures to support our root cause investigation”, the spokesperson added.

Regulatory scrutiny has extended beyond the manufacturer. In December, the FDA issued warning letters to four major US retailers for failing to remove the recalled products from their store shelves.

Nestlé recall linked to third-party-supplied arachidonic acid oil

Separately, on January 6, 2026, Nestlé initiated a voluntary recall of certain infant and follow-on formula batches across 49 countries, due to the detection of Bacillus cereus or its heat-stable toxin, cereulide.

Nestlé traced the contamination back to arachidonic acid oil, a long-chain polyunsaturated fatty acid, supplied to the company by a third-party ingredient manufacturer. The oil is commonly added to infant formulas to mimic breast milk's arachidonic acid, which supports cognitive function, visual acuity, and immune system development in non-breastfed babies.

Bacillus cereus is a spore-forming bacterium commonly found in the environment and is a known risk in relation to the production of dried foods. Heat treatment can inactivate the bacterium; however, cereulide is resistant to heat and many processing steps, making prevention at the ingredient level essential.

Symptom onset depends on whether the illness is caused by the bacterium (6 to 24 hours) or the toxin (30 minutes to 6 hours). Symptoms include vomiting, diarrhoea, and abdominal discomfort.

No illnesses confirmed in connection to Nestlé recall

A spokesperson for Nestlé said the company had tested all arachidonic acid oil and corresponding oil mixes used in the production of potentially impacted infant nutrition products and that no illnesses had been confirmed in connection with the products involved to date.

The spokesperson said that Nestlé has been in contact with UK authorities and, as a precautionary measure, was recalling specific batches of its SMA-branded infant formula and follow-on formula.

Broader scrutiny of infant nutrition safety

The ByHeart and Nestlé recalls are occurring amid growing scrutiny of infant nutrition safety and regulatory oversight.

In March 2025, US consumer advocacy group Consumer Reports tested 41 types of powdered formula for contaminants, including arsenic and lead, finding that around half of the tested samples contained potentially harmful levels of at least one substance.

Following the ByHeart recall, an open letter on behalf of the Safe Food Coalition was sent to the FDA, the Centers for Disease Control and Prevention (CDC) acting director Jim O’Neill, and the US health secretary Robert F. Kennedy, Jr., calling for stronger federal action and urging regulators to tighten infant formula oversight.

Beyond safety concerns, the recalls have had financial implications. Nestlé shares fell by more than 4%, and analysts told the Financial Times that the recall could cost an estimated €1.29 billion.