A food handler's clothing exists for one purpose: to stop the person's body, hair and everyday clothes from ever coming into contact with the food being prepared. Working through the outfit from head to toe shows how each item serves that purpose.
Head: A cap, hairnet or similar covering keeps loose strands of hair from falling into food, since hair is one of the most common sources of physical contamination in a kitchen.
Body: A clean uniform or apron worn over regular clothes acts as a barrier, catching spills, grease and dirt that would otherwise transfer from the handler's own clothing onto the food or work surfaces. It is changed as soon as it becomes soiled.
Hands: Disposable gloves are worn whenever the food will be eaten without further cooking, protecting the food from anything on the handler's hands, and they are always used along with, not instead of, regular handwashing.
Feet: Closed, non-slip shoes protect the handler from spills and hot liquids while also preventing slips on wet kitchen floors, keeping both the person and the food preparation process safe.
Therefore, a food handler should wear a clean uniform or apron, a head covering, gloves when handling ready-to-eat food, and closed non-slip footwear, each item working together to keep the food free from contamination.