Avoiding Surcharges. Because airlines charge a peak travel day surcharge on the most popular days of travel -- Sunday, Monday and Friday -- you can get the best discounts on those off-peak days. However, during the summer, peak and off-peak travel days do not really exist.
Proteins are essential nutrients for the human body. They are one of the building blocks of body tissue, and can also serve as a fuel source. As a fuel, proteins contain 4 kcal per gram, just like carbohydrates and unlike lipids, which contain 9 kcal per gram.
Updated December 07, 2016. Protein is one of the basic building blocks of the human body, making up about 16 percent of our total body weight. Muscle, hair, skin, and connective tissue are mainly made up of protein. Additionally, protein plays a major role in all of the cells and most of the fluids in our bodies.