Our family menu plans look like a juggling routine that seems to work out somehow. Here are the diets we're working:
Allergenic: Araminta, Tarquin, and Lucinda all have an unidentified Hyper IgE Syndrome. This means, among other things, that they are classically allergic to most foods. Tarquin is our little guy, 5 1/2. He was allowed to try his first food at age 5 and now has 3 safe foods: rice, turkey, and potatoes. The little girls have more safe foods but it still isn't a diet that anyone in a first world country would really recognize.
Paleo: Sophia and I each have health issues that have taken us off grain/gluten/starch. Fortunately for us, the "Paleo" or "Primal" diet fits what we need to do anyway quite well. We are able to have dairy, and Sophia can also tolerate sugar. I am sugar free (including only judicious, targeted use of fruit). Later addition: The Patriarch has gone Paleo as well due to an experience with some nasty kidney stones. He also avoids oxalates.
Jamaican: My husband grew up in Jamaica, and most often cooks for himself. He doesn't eat beef or pork, and while he'll try a dessert to be polite, he isn't much for sweets.
Nut free: You'll see substitutes for nuts quite often on this blog. Clara is allergic to peanuts and tree nuts, all but pecans and cashews, so those are the two forms of nuts we use here. We also discovered early in the timeframe of this blog that she reacts to the smallest amount of sesame oil with her throat starting to close up, so not going there anymore.