The EU Food Information for Consumers Regulation requires 14 allergens including nuts, gluten and mustard to be either listed on menus or have their presence communicated by staff.
The law was initially met with criticism from the catering industry, with over 100 top chefs and restaurateurs including Wahaca co-founder Thomasina Miers and Albert Roux singing a letter slamming the law as a 'bureacratic nightmare' that reduced 'creativity and innovation' in cooking.
A 2015 study by the Food Allergy Training Consultancy found that over a third of people with allergies thought menu information was 'confusing' and just 10% felt confident eating out.
But the new research indicates a shift in attitudes, with 70% of diners saying they now feel more confident about asking staff for information.
Customers said that the laws had led to them eating out more frequently and that they were more likely to return to and recommend restaurants with staff that were knowledgeable about allergies and intolerances.
Over 2m people in the UK have a food allergy, and an estimated 600,000 have coeliac disease.
The research found that post-legislation 63% felt they could talk to a chef about their allergen needs, and 44% were more ‘adventurous’ about eating out.
An increasing number of high street restaurants including Browns and PizzaExpress now offer gluten-free menus.
“Some, often smaller, food businesses haven't got on top of providing allergen information yet,” said Heather Hancock, chairman of the Food Standards Agency, which commissioned the report.
“I hope this research helps them see the importance of meeting their obligations and the benefits it delivers.”