Magnesium sources in diet
The free element (metal) can be produced artificially, and is highly reactive (though in the atmosphere, it is soon coated in a thin layer of oxide that partly inhibits reactivity — see passivation ). Table of Contents Introduction Recommended Intakes Sources of Magnesium Magnesium Intakes and Status Magnesium Deficiency Groups at Risk of Magnesium Inadequacy Magnesium and Health Health Risks from Excessive Magnesium Interactions with Medications Magnesium and Healthful Diets References Disclaimer. Historically, magnesium was one of the main aerospace construction metals and was used for German military aircraft as early as World War I and extensively for German aircraft in World War II. Magnesium has three stable isotopes: 24 Mg, 25 Mg and 26 Mg. Tolerable Upper Intake Level (UL): maximum daily intake unlikely to cause adverse health effects. Magnesium is highly flammable, especially when powdered or shaved into thin strips, though it is difficult to ignite in mass or bulk. Magnesium powder is used in fireworks and marine flares where a brilliant white light is required. When such stars explode as supernovas, much of the magnesium is expelled into the interstellar medium where it may recycle into new star systems. When submerged in water, hydrogen bubbles form slowly on the surface of the metal—though, if powdered, it reacts much more rapidly. DRI is the general term for a set of reference values used to plan and assess nutrient intakes of healthy people. In the United States, magnesium is obtained principally with the Dow process, by electrolysis of fused magnesium chloride from brine and sea water. As of 2013, magnesium alloy consumption was less than one million tons per year, compared with 50 million tons of aluminum alloys. It is usually used to assess the adequacy of nutrient intakes in population groups but not individuals. Magnesium is required for energy production, oxidative phosphorylation, and glycolysis. Sufficient manganese overcomes the corrosive effects of iron. In 1618, a farmer at Epsom in England attempted to give his cows water from a well there. Magnesium reacts with water at room temperature, though it reacts much more slowly than calcium, a similar group 2 metal. Breakfast cereals, fortified with 10% of the DV for magnesium. Selected food sources of magnesium are listed in Table 2. Magnesium, an abundant mineral in the body, is naturally present in many foods, added to other food products, available as a dietary supplement, and present in some medicines (such as antacids and laxatives). Magnesium is less dense than aluminium, and the alloy is prized for its combination of lightness and strength. Although magnesium is found in more than 60 minerals, only dolomite, magnesite, brucite, carnallite, talc, and olivine are of commercial importance. Adequate Intake (AI): established when evidence is insufficient to develop an RDA and is set at a level assumed to ensure nutritional adequacy. When burning in air, magnesium produces a brilliant-white light that includes strong ultraviolet wavelengths. The United States has traditionally been the major world supplier of this metal, supplying 45% of world production even as recently as 1995. It tarnishes slightly when exposed to air, although, unlike the other alkaline earth metals, an oxygen-free environment is unnecessary for storage because magnesium is protected by a thin layer of oxide that is fairly impermeable and difficult to remove. To extract the magnesium, calcium hydroxide is added to seawater to form magnesium hydroxide precipitate. It is a shiny gray solid which bears a close physical resemblance to the other five elements in the second column (Group 2, or alkaline earth metals ) of the periodic table: all Group 2 elements have the same electron configuration in the outer electron shell and a similar crystal structure. Magnesium ( Mg ) is not to be confused with manganese ( Mn ). This anomalous abundance is attributed to the decay of its parent 26 Al in the inclusions, and researchers conclude that such meteorites were formed in the solar nebula before the 26 Al had decayed. The metal is now obtained mainly by electrolysis of magnesium salts obtained from brine, and is used primarily as a component in aluminium -magnesium alloys, sometimes called magnalium or magnelium. An unusual application of magnesium as an illumination source while wakeskating in 1931. A new process, solid oxide membrane technology, involves the electrolytic reduction of MgO. The metal itself was first produced by Sir Humphry Davy in England in 1808. Magnesium is also added to some breakfast cereals and other fortified foods. Food and Drug Administration (FDA) to help consumers compare the nutrient contents of products within the context of a total diet. Computer Access to Research on Dietary Supplements (CARDS) Database.
A layer of graphite borders the liquid metal anode, and at this interface carbon and oxygen react to form carbon monoxide. The isomer 26 Mg has found application in isotopic geology, similar to that of aluminium. S. It contributes to the structural development of bone and is required for the synthesis of DNA, RNA, and the antioxidant glutathione. In general, foods containing dietary fiber provide magnesium. The isotope 28 Mg is radioactive and in the 1950s to 1970s was produced by several nuclear power plants for use in scientific experiments. Magnesium also reacts exothermically with most acids such as hydrochloric acid (HCl), producing the metal chloride and hydrogen gas, similar to the HCl reaction with aluminium, zinc, and many other metals. Estimated Average Requirement (EAR): average daily level of intake estimated to meet the requirements of 50% of healthy individuals. The free metal burns with a characteristic brilliant-white light. These values, which vary by age and sex, include. The salt is then electrolyzed in the molten state. All are present in significant amounts (see table of isotopes above). 26 Mg is a radiogenic daughter product of 26 Al, which has a half-life of 717,000 years. Magnesium is used in super-strong, lightweight materials and alloys. Excessive quantities of stable 26 Mg have been observed in the Ca-Al-rich inclusions of some carbonaceous chondrite meteorites. This isotope has a relatively short half-life (21 hours) and its use was limited by shipping times. Hundreds of enzymes require magnesium ions to function. Elemental magnesium is a gray-white lightweight metal, two-thirds the density of aluminium. The hydroxide is then converted to a partial hydrate of magnesium chloride by treating the hydroxide with hydrochloric acid and heating of the product. The presence of iron, nickel, copper, and cobalt strongly activates corrosion. Magnesium is the third-most-commonly-used structural metal, following iron and aluminium. Magnesium is widely distributed in plant and animal foods and in beverages. These are among the oldest objects in the solar system and contain preserved information about its early history. DVs were developed by the U. This presented a serious problem for the earliest models of the Boeing B-29 heavy bomber when an in-flight engine fire ignited the engine crankcase. In the commercial aerospace industry, magnesium was generally restricted to engine-related components, due fire and corrosion hazards. Magnesium hydroxide ( brucite ) is insoluble in water and can be filtered out and reacted with hydrochloric acid to produced concentrated magnesium chloride. This prevents the formation of free hydrogen gas, an essential factor of corrosive chemical processes. Less than 1% of total magnesium is in blood serum, and these levels are kept under tight control. Wright Aeronautical used a magnesium crankcase in the WWII-era Wright Duplex Cyclone aviation engine. This property was used in incendiary weapons during the firebombing of cities in World War II, where the only practical civil defense was to smother a burning flare under dry sand to exclude atmosphere from the combustion. Magnesium forms a variety of compounds important to industry and biology, including magnesium carbonate, magnesium chloride, magnesium citrate, magnesium hydroxide (milk of magnesia), magnesium oxide, magnesium sulfate, and magnesium sulfate heptahydrate ( Epsom salts ). China is the dominant supplier of magnesium, with approximately 80% of the world market share. Beef, ground, 90% lean, pan broiled, 3 ounces. Magnesium may also be used as an igniter for thermite, a mixture of aluminium and iron oxide powder that ignites only at a very high temperature.
