This immunity supporting smoothie features lemon juice (for vitamin C), sunflower seeds (for vitamin E), and yogurt (for gut-healthy probiotics). Smoothies are delicious and easy, and perfect for on-the-go breakfasts because they are quick to make and easily portable. Generally, frozen or fresh fruit and veggies, pureed with a liquid and often yogurt for protein. They are also great ways to use up any leftover fruits or veggies you have on hand. Feel free to swap ingredients for what you might have in your fridge or freezer.