I've been a vegetarian since 1984. Mainly for philosophical reasons, but also for health reasons. I don't think it's natural for humans to eat lots of meat. However, I especially don't think that eating animals that have been fed lots of junk and raised in emotionally challenging circumstances is healthy.
We recently had our dietary lives turned upside down because of our daughter's sensitivities. So, no gluten, no dairy, no cane sugar (though beet sugar would be fine,) and no tomatoes.
And I LOVE this diet. It is so much healthier than what we ate before. Although I'd always tried to avoid stock foods with sugar in them, I would buy some things like Chex cereal. Now I can't do that. Also, I don't buy processed gluten free foods. They are low fiber, tasted bad, and are expensive. Instead I've done lots of searching for alternative. I now cook with a lot of coconut milk (great for creamy soups and ice cream.) I make tortillas out of mung beans, we eat more beans and nuts. I cook with Trader Joe's rice milk or Rice Dream rather than cow's milk. (I try to avoid soy and most dairy-free milks have carageenan, which I've read is an intestinal irritant--something she doesn't need.)
Basically, what has happened is we have been forced to find a wider variety of healthier foods. My husband and I used to joke that all we ate was macaroni and cheese. EVERYTHING we ate seemed to have wheat and cheese in it. Now we must be original--sauteed green beans with almonds and shitake mushrooms over brown rice. Cream of broccoli soup made with potatoes, broccoli, and coconut milk.
So, since you don't have mandatory dietary restrictions, slowly start looking around for vegetarian, gluten free, dairy-free recipes that you find yummy. Start slowly so you don't get burned out and see what yummy foods you come across. The point isn't necessarily to exclude all meat, gluten, milk, and sugar from your diet, but rather to open yourself up to new, healthier foods.
Also, check out www.elanaspantry.com. She cooks mainly with almond flour. She uses a lot of agave syrup but I generally replace with honey instead. So, when I make bread, I know my kids are eating almonds. Same with cupcakes and cookies. Plus her stuff is so tasty.
So find healthy foods that you like to eat.