A grieving family’s call for a law compelling restaurants to put full allergen information on menus has been coolly received by the body representing the industry because of the extra costs involved at a time when many businesses are struggling.

Owen Carey died from anaphylactic shock after eating a burger that had been marinaded in buttermilk. On Friday a coroner ruled he was misled into believing the burger was safe for him to eat because he had warned staff he was allergic to dairy products.

His family have called for a change in the law so all menu items are labelled with potential allergens – similar to “Natasha’s law” which obliges food businesses to include full labelling on pre-packaged food. It was introduced after 15-year-old Natasha Ednan-Laperouse died from eating a Pret-a-Manger baguette that contained sesame seeds.

But Kate Nicholls, the chief executive of UKHospitality, said a law change could have a serious impact on the viability of some of the 100,000 restaurants her organisation represents. “Hospitality and particularly high street restaurants are under intense cost pressures and are struggling,” she said. We’ve had a number of high-profile casualties on the high street. Those businesses operate on tight net profit margins. And there’s no doubt some would not be able to cope with any significant change in their cost structure.”

Restaurants are already required by law to provide allergen information on request, Nicholls said, adding that the best way to prevent further tragedies would be better staff training. She fears menus could become overloaded with information and restaurants that changed menus daily, particularly small independent restaurants, would find it hard to comply.

“Ingredient declarations on the menu isn’t necessarily straightforward, and won’t necessarily protect all of our customers,” Nicholls said.

“We’re keen to keep our customers safe, and do the right thing and that comes down to two-way communication. So much of this can be affected by the way in which a product is cooked or prepared, not just about the raw ingredients.”

Carey’s family believe that relying on serving staff to communicate is not enough. Allergy sufferers say they are sometimes not believed by people, including chefs, that eating the wrong food could be life-threatening. Carey did tell serving staff about his allergies, Southwark coroners’ court heard. The A-level student, from Crowborough, East Sussex, had been celebrating his 18th birthday with his girlfriend on a day out in London. The inquest heard that his chicken burger had been marinated in buttermilk, but the menu reassured him that it was safe to eat. Carey’s sister, Emma Kocher, said outside court: “It is simply not good enough to have a policy which relies on verbal communication between the customer and their server, which often takes place in a busy, noisy restaurant where the turnover of staff is high and many of their customers are very young.”

Nicholls acknowledged that arguments against putting full allergen information on menus were similar to those the food industry had made against Natasha’s law, which ministers introduced earlier this month. From October 2021, sandwich shops and cafes will need to carry a full list of ingredients on pre-packed food.

“It’s going to be incredibly challenging for small coffee shops and sandwich shops,” Nicholls said, adding that ministers had looked at extending the new legislation to cover restaurants and decided not to.

Natasha Ednan-Laperouse’s death, after eating a baguette containing sesame seeds, led to the creation of ‘Natasha’s law’ which will require all pre-packed food to be fully labelled with allergens by 2021. Photograph: Family Handout/PA

Although deaths from anaphylactic shock caused by food have made headlines in recent years, there are no exact figures on how many people die each year, said Grace Brocklehurst of the Anaphylaxis Campaign, which lobbied for Natasha’s law and supported Carey’s family at the inquest.

“We don’t know how many people are allergic. Deaths are stable, we think it’s around 10 to 20 a year, but we don’t know because some allergy deaths are recorded as asthma induced anaphylaxis,” Brocklehurst said, backing calls for a national register of anaphylactic deaths. Brocklehurst added that the government needs to reduce waiting times for people to see allergen consultants. “It’s a postcode lottery. If you’re in the south of England you’ll likely be seen sooner than in the north and we don’t believe that’s right.”

The Anaphylactic Campaign’s helpline had been called recently by a man in his 50s who had suffered a bee sting.

“He doesn’t have an appointment until June of next year to see a specialist. That’s an awful long time to wait for a referral. He doesn’t know [if he’s stung again] that he’s just going to get a very itchy arm or if he’s going to suffer anaphylactic shock. And he doesn’t have access to adrenaline which is the safest drug available. And that’s an awful thing for someone to go through.”