When RSVPing to a party, mention your dietary restrictions and allergies: “Thanks for the invitation. I must tell you that I am vegan and gluten-free. I am also allergic to peanuts.” Be as specific as possible; mention if you can consume milk products and eggs. Elaborate if you can’t eat anything particular: butter, marshmallows, honey, gelatin, chicken stock, or lard in desserts.
Offer to provide for yourself and help out: “May I bring my five-bean and avocado salad with baked nachos? That should also cover the appetizer course for you!” If you’re comfortable with meat substitutes, offer to bring the meat-alternative dish that’s most suitable for the occasion: “May I bring a Tofurky dish? I’ve heard it mimics the taste and texture of a Thanksgiving meal.”
If the party is in your honor and the host insists upon cooking for you, suggest an easy dish they could prepare for you. Don’t make the host search for a dish that best suits your preferences.
Understand that your hosts can’t cater to every guest’s preferences. Don’t be offended if your host forgets about your dietary restrictions. Appreciate that they’ll be spending a lot of time preparing for and cleaning up after the party. If your host hasn’t made any accommodations to cover your dietary needs, just eat salad, quick-and-easy canned soup, or whatever is practical for the host to organize quickly for you. Don’t grumble.