Protein bars are an easy and portable protein source. Pop one in your purse or carry-on and you are sure of something healthy and on plan to power your day. I always have a protein bar on me. You never know when your appointment will run late or plane will be delayed when traveling. I have checked-in to a hotel later than anticipated only to find my choices for dinner were a late night room service menu of overpriced deep fried foods or a vending machine filled with 400-calorie who knows how old pastries.