What's the secret to hosting a memorable dinner party? For 29-year-old Sarah Waybright, it's a trifecta of good company, good food and good wine — plus a menu that won't leave guests feeling sick, stuffed or guilt-ridden.

"When you think about 'treating' yourself, it's about instant gratification," says Waybright, a registered dietitian and the woman behind WhyFoodWorks, a healthful dinner-party service based in Washington. "You go to a wedding, a birthday party or dinner at someone's house and everything looks delicious, then you overeat and feel (terrible) at the end of the night. But you don't have to binge to celebrate."

Through WhyFoodWorks events — which feel like a cooking show in your kitchen — Waybright aims to teach people how to balance flavor with nutrition and social interaction with personal well-being. Wine pairings and dessert, such as a slice of grain-free Coconut "Cheesefake," keep the educational meals lively and festive.