A 12-year-old’s death from a Twix milkshake has highlighted an insidious way even so-called “safe foods” can prove deadly to people with severe nut allergies.
The victim, Mia Shay St Hilaire, had reportedly ordered the sweet beverage at the Pop Inn in London while visiting with her aunt and sister.
While the shake didn’t have any tree nuts — the source of her life-threatening allergy — she subsequently “developed rapidly progressing anaphylaxis” and ended up collapsing at her aunt’s home. Despite being rushed to the hospital, the youngster tragically passed away shortly after arriving, the coroner’s office said.
How did this supposedly benign beverage cost St Hilaire her life? According to CCTV reports, the restaurant’s owner Baris Yucel had used the same blender to whip up a hazelnut-harboring Kinder Bueno milkshake and didn’t wash it before prepping the preteen’s order — an issue known as allergen cross-contact.
“No family should ever have to lose a child in these circumstances,” the girl’s parents said in a statement, adding that they wanted to use their daughter’s tragedy to help “save lives in the future.”
Invisible epidemic?
While her death might seem like a freak occurrence, cross-contact is more common than one might think.
According to a 2024 study, cross-contact accounted for 29% of the unintentional food allergen exposures reported by participants in a Food Allergy Research & Education (FARE) registry, 77% of whom reported at least one accidental exposure.
“There’s a lot of fear around food allergies and things like this are the reason why,” Dr. Ruchi Gupta, founding director of the Center for Food Allergy & Asthma Research (CFAAR), told the Post. “When you know that you can have an accidental exposure like this and then have a death happen is just horrible.”
This is problematic given that each year in the US, 3.4 million patients (the population of Oklahoma) visit the emergency room due to a food allergy reaction, according to Food Allergy Research and Education.
Meanwhile, one in 13 children suffer from food allergies in the US, and 42% of them have had a severe reaction to food.
Why so insidious
Cross-contact is particularly insidious as the victim can be meticulous about what they can consume and still suffer a deadly allergic reaction.
When it comes to tree nuts, even microscopic doses can cause major problems. In a 2013 study, researchers found that just 0.29 milligrams of hazelnut protein — around a third the mass of a grain of salt — could trigger an allergic reaction in 5% of children.
In 2024, Boston bombshell Caroline Cray Quinn claimed that just smooching someone who’d been exposed to her many allergens, including tree nuts, could prove fatal for her — the literal kiss of death.
“Everyone has different thresholds for how much they can handle of their allergen,” said Gupta, who is also a Professor of Pediatrics and Medicine at Northwestern University Feinberg School of Medicine. “And it’s really important to know if your threshold is very low because you have to be even more hypervigilant.
Restaurant responsibility
According to FARE. restaurants are second to homes when it comes to causing food allergy reactions — a trend experts blame on their lack of preparedness.
In 2024, researchers in Spain and Chile conducted an international review of 23 studies examining restaurant workers’ food allergy knowledge and safety practices, finding notable deficits in both despite employee willingness to help affected diners.
“And then they have a whole precautionary list of what to do if you say yes [to the allergy question],” said Dr. Gupta, whose college-age daughter suffers from food allergies. “And that’s great, but obviously it’s not happening all the time.”
“Restaurants need to have a protocol and training for food allergies.”
What can restaurants do
Thankfully, the allergy expert said that restaurants can reduce the chances of a patron experiencing adverse reactions through a variety of measures. Number one? Asking if there are any food allergies and then following the proper protocol.
“So many times I’ve been with my daughter at one of these places,” said Dr. Gupta. “And they’re like, ‘just a second’ and they go and they grab their procedure manual and tell you if [the allergen’s’] in it, if it may contain it, and then they have a procedure of how to prepare that food for that individual.”
Other procedures, per Gutpa, include cleaning scoopers and other utensils between use, labeling foods that contain any of the most common allergens, and hopefully, in the future, stocking norepinephrine on site.
Meanwhile, an investigation into preventative measures by the US Food & Drug Administration (FDA) found that thorough cleanings involving a wash-rinse-sanitize-air dry method was effective at eradicating allergens and curbing contamination.
Pre-scraping food from surfaces before cleaning helped facilitate allergen removal as well.
Meanwhile, wet cloths/wipes and alcohol wipes proved far more effective than dry wipes at cleaning allergen while storing cloths in sanitizer helped mitigate the transfer of problem ingredients between surfaces.
Finally, per the FDA study, allergens were more difficult to remove from textured plastic than stainless steel or wood surfaces.
Individual protections
Individuals must also do their part to mitigate the chances of a dangerous incident while dining out.
This means making “sure you see your allergist” and learning about potential triggers and the threshold that can cause them, according to Dr. Gupta.
Number two is ensuring that the employees are abreast of allergy protocol and don’t reuse contaminated cookware.
“Make sure you ask, ‘I do have this allergy, do you mind using a different scooper or do you mind using a different pan?’” advised Gupta.
Finally, it’s paramount that people carry their epi pen or other norepinephrine dispenser on hand.
“Carry your epinephrine and don’t be afraid to use it,” she said. “The second you start feeling those symptoms come on, epinephrine, just have it on hand and use it immediately.”
Regulations
Unfortunately, US food allergy safety regulations vary by state and city, while the UK has more standardized regulations mandating that food businesses declare any regulated allergens, including tree nuts.
Following St Hilaire’s death in August 2023, the Pop Inn was forced to pay £18,000 (about $24,000) in fines while Yucel admitted to food safety violations ranging from not making allergen advice available or visible to customers to failing to manage contamination during food production
As punishment, the disgraced owner was required to serve 100 hours of community service and no longer owns or operates the cafe.
Thankfully, Gupta claims that “there are a lot of US policies in place or under review” to make restaurants and other venues safer for allergy sufferers.
In September, the FDA released an updated 2026 edition of the Food Code, clarifying guidance on allergen cross-contact and adding a new framework for managing major food allergens.
However, the code serves as guidelines for state and local regulators rather than a binding law.
Nonetheless, Dr. Gupta believes we’re making strides.
“20 years ago we didn’t have a lot of awareness,” she said. “People didn’t know about it and understand it and it’s getting better and better, but it just shows me there’s still a lot more to do.”
