A new composition of nanosized bagasse fibers has been made by a method which reduces the sugarcane bagasse fibers to nano-sized particles while retaining the natural components of the bagasse. The resulting bagasse particles were shown to be effective as a nutritional supplement in a mouse model to aid in glucose control and body weight. Using the bagasse nanofibers, the addition of 5 to 10% fiber did not change the color or texture of food products. Moreover, the bagasse powder has a natural color and absorbs color evenly so that it could be used as a natural foundation material for cosmetic products.