The steel cable of a colliery winding tower. Steel is an alloy of iron and other elements, primarily carbon, that is widely used in construction and other applications because of its high tensile strength and low cost. Steel's base metal is iron, which is able to take on two crystalline forms (allotropic forms), body centered cubic and face centered cubic (FCC), depending on its temperature.
: Appendix B: Vitamin and Mineral Deficiencies in the U.S. Some American adults get too little vitamin D, vitamin E, magnesium, calcium, vitamin A and vitamin C (Table B1). More than 40 percent of adults have dietary intakes of vitamin A, C, D and E, calcium and magnesium below the average requirement for their age and gender. Inadequate intake of vitamins and minerals is most common among 14-to-18-year-old teenagers. Adolescent girls have lower nutrient intake than boys (Berner 2014; Fulgoni 2011). But nutrient deficiencies are rare among younger American children; the exceptions are dietary vitamin D and E, for which intake is low for all Americans, and calcium.
According to a report in the Harvard Health Newsletter, vitamin B12 deficiency is the most common nutrient deficiency in the developing world and the United States [2] . Other studies estimate that nearly 50% of all older individuals are deficient in B12 [3] .Signs and symptoms of a B12 deficiency include the following: 1  Low Energy and Weakness. 2  Confusion or âfuzzinessâ. 3  Persistent sleep problems. 4  Digestive problems. 5  Hearing and vision loss. 6  Memory problems.7  Irritability and mood swings.ther studies estimate that nearly 50% of all older individuals are deficient in B12 [3] . Signs and symptoms of a B12 deficiency include the following: 1  Low Energy and Weakness. 2  Confusion or âfuzzinessâ. 3  Persistent sleep problems. 4  Digestive problems. 5  Hearing and vision loss. 6  Memory problems. 7  Irritability and mood swings.