“That’s why there is such a cautious approach to food, particularly in the days leading up to major engagements. Anything that carries even a relatively small chance of causing food poisoning, stomach issues or digestive discomfort is carefully assessed and, in many cases, avoided altogether. The thinking is simple – why take an unnecessary risk when there are so many responsibilities depending on you being fit and well?
“It’s not about being overly restrictive or living under constant rules. It’s about minimizing avoidable problems. Catherine has obligations that require her to be meeting people, speaking publicly and traveling extensively, so maintaining her health is viewed as an important part of the role.”
The insider added: “Most people can take a sick day if they’re feeling unwell. For a senior member of the Royal Family, it’s far more complicated than that. There are security arrangements, diplomatic considerations, media commitments and thousands of people who may have spent months preparing for a visit. That’s why precautionary measures, even seemingly small ones involving food and drink, are taken very seriously behind the scenes.”
Garlic and raw onions are also said to be largely absent from Catherine’s diet when she is undertaking public engagements.
The restriction stems from concerns over lingering breath odors during meetings and official receptions.
Queen Camilla, 78, acknowledged the practice during an appearance on MasterChef Australia when she said: “Garlic is a no-no…You always have to lay off the garlic.”
Catherine is also prevented from eating foie gras at royal residences following a long-standing policy introduced by King Charles, 77.
The luxury dish, made from the liver of force-fed ducks or geese, was effectively removed from royal menus because of concerns about animal welfare.
Spicy food occupies a more complicated place in Catherine’s diet.
While heavily spiced meals are often avoided during official tours because they can trigger digestive discomfort, the princess has previously revealed she enjoys heat when cooking at home.
Speaking in 2019, she said: “It’s so hard cooking curry with the family… the children have a portion with no spice, (William’s) is medium. And I quite like it hot. Charlotte is pretty good with heat.”

