The condition arising due to the lack of one or more of the nutrients that are required in the diet to maintain health. Malnutrition can result from a reduced intake of nutrients (undernourishment), an inability to use absorbed nutrients, failure to meet a required increase in nutrient intake, or nutrient losses. There are three stages in the process of malnutrition: first, the carbohydrate stores in the body are depleted; secondly, the fat reserves are metabolized (see fatty-acid oxidation); and finally, proteins are broken down to provide energy. Death may result after protein levels have been reduced to half their normal value. Kwashiorkor is a type of malnutrition that develops when the diet lacks proteins and hence essential amino acids. Malnutrition due to reduced absorption of nutrients in the intestine can develop with a cereal-based diet, due to sensitivity of the intestinal lining to gluten, a protein found in cereals. See also mineral deficiency.