If your tour includes a meal organised by the guide do make sure you mention if you have dietary requirements and be specific about them before you settle on an itinerary and book. The guide will take these into consideration when booking or recommending restaurants.
|Valencay cheese, one of the famous Loire Valley goats cheese.|
In rural France particularly, restaurants often do not offer extensive a la carte menus, but daily changing seasonal limited choice set menus. Don't wait until you are seated in the restaurant to tell your guide that you are vegan, coeliac or lactose intolerant. That will be too late and the restaurant, no matter how sympathetic, may not be able to meet your dietary requirements in a way that you find satisfactory.
The ingredients in the kitchen on a daily basis will be limited and seasonal. Restaurants operate in this way because it is illegal, uneconomical, and disrespectful to waste food in France. Most French diners in traditional French restaurants have grown up trusting the chefs in these places to produce a delicious meal. Almost everyone will choose the dish of the day. No one will request anything not on the menu, or that a dish is changed to suit them, unless they have diagnosed food allergies.