Micronutrient deficiency
Micronutrient deficiency or dietary deficiency is not enough of one or more of the micronutrients required for optimal plant or animal health. In humans and other animals they include both vitamin deficiencies and mineral deficiencies, whereas in plants the term refers to deficiencies of essential trace minerals. Humans. Micronutrient deficiencies affect more than two billion people of all ages in both developing and industrialized countries. Micronutrient deficiency adversely affects the physiology and immunology of an individual, causing long term health consequences. They are the cause of some diseases, exacerbate others and are recognized as having an important impact  on worldwide health. Important micronutrients include iodine, iron, zinc, calcium, selenium, fluorine, and vitamins A, B, B, B, B, B, B and C. The population mostly affected by micronutrient deficiency are infants, children and adolescents, women of childbearing age, pregnant women and the elderly. Micronutrient deficiencies are associated with 10% of all children's deaths, and are therefore of special concern to those involved with child welfare. Early childhood micronutrient deficiency leads to stunted growth and impaired cognitive development. Deficiencies of essential vitamins or minerals such as Vitamin A, iron, and zinc may be caused by long-term shortages of  nutritious food or by infections such as intestinal worms. They may also be caused or exacerbated when illnesses (such as diarrhoea or malaria) cause rapid loss of nutrients through feces or vomit. There are several interventions to improve the micronutrient status including fortification of foods, supplementation and treatment of underlying infections. Implementation of appropriate micronutrient interventions has several benefits, including improved cognitive development, increased child survival, and reduced prevalence of low birth weight. Plants. In plants a micronutrient deficiency (or trace mineral deficiency) is a physiological plant disorder which occurs when a micronutrient is deficient in the soil in which  a plant grows. Micronutrients are distinguished from macronutrients (nitrogen, phosphorus, sulfur, potassium, calcium and magnesium) by the relatively low quantities needed by the plant. A number of elements are known to be needed in these small amounts for proper plant growth and development. Nutrient deficiencies in these areas can adversely affect plant growth and development. Some of the best known trace mineral deficiencies include: zinc deficiency, boron deficiency, iron deficiency, and manganese deficiency.