Even though the 20 Years Younger plan recommends eating about 1,700 calories a day, it's important to remember that healthy eating isn't just about counting calories. Janis says certain superfoods can be a fountain of youth and significantly improve your health.

"[For the plan] we chose specific foods—almonds, eggplant, high-fiber grains—that lower the cholesterol," Janis says.

She also has an easy trick for packing more nutritional punch into every meal: Make your plate colorful. According to Janis, the more color on your plate, the higher the nutritional value. "You're getting a wealth of phytonutrients that way." 

Watch this class on healthy cooking!