Food is any substance consumed to provide nutritional support for the body. It is usually of plant or animal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals. The substance is ingested by an organism and assimilated by the organism's cells in an effort to produce energy, maintain life, or stimulate growth.
Historically, people secured food through two methods: hunting and gathering, and agriculture. Today, most of the food energy consumed by the world population is supplied by the food industry.
A food allergy is an adverse immune response to a food protein. They are distinct from other adverse responses to food, such as food intolerance, pharmacological reactions, and toxin-mediated reactions.
The protein in the food is the most common allergic component. These kinds of allergies occur when the body's immune system mistakenly identifies a protein as harmful. Some proteins or fragments of proteins are resistant to digestion and those that are not broken down in the digestive process are tagged by the Immunoglobulin E (IgE). These tags fool the immune system into thinking that the protein is an invader. The immune system, thinking the organism (the individual) is under attack, sends white blood cells to attack, and that triggers an allergic reaction. These reactions can range from mild to severe. Allergic responses include dermatitis, gastrointestinal and respiratory distress, including such life-threatening anaphylactic responses as biphasic anaphylaxis and vasodilation; these require immediate emergency intervention. Individuals with protein allergies commonly avoid contact with the problematic protein. Some medications may prevent, minimize or treat protein allergy reactions. There is no cure.
Gluten sensitivity (also gluten intolerance) is a spectrum of disorders including celiac disease in which gluten has an adverse effect on the body. Symptoms include bloating, abdominal discomfort or pain, diarrhea, muscular disturbances and bone or joint pain. It can also cause other unexpected symptoms such as headaches and vertigo, among many others.
Gluten gives elasticity to dough helping it to rise and to keep its shape. It is found in many staple foods in the Western diet. It is a protein composite found in wheat and other grains, including barley and rye and processed foods thereof. Gluten is composed of a gliadin fraction (alcohol soluble) and a glutenin fraction (only soluble in dilute acids or alkali). Gluten is not naturally occurring in corn, rice, or oats.