Lithium

Lithium is a silvery-white light metal that belongs to the alkali metals. It has the atomic number 3 in the periodic table of elements and the chemical symbol Li. The name is derived from the Greek word for stone = lithos. It has a density of 0.53 g/cm3 and therefore floats on water. However, it reacts with water to form lithium hydroxide and hydrogen. It was discovered by the Swedish chemist Johan August Arfvedson (1792-1841) in 1817. It is not found in elementary form on earth and is the 27th most common element in the earth's shell. It occurs in around 150 compounds, of which spodumene (LiAl(SiO3)2, for example, is one of the most productive lithium compounds. In technology, it is mainly used as an alloy, e.g. together with lead for hardened bearings or together with magnesium in space technology. It is also used as lithium fluoride for the coating of optical lenses and for the production of UV-permeable glass. It now plays an important role as an anode material in very long-lasting batteries, e.g. in medicine as pacemaker batteries. As lithium stearate, it is used in the mineral oil industry as a thickening agent in oils for the production of lubricating greases. In pyrotechnics, it is used to produce crimson glow effects.

Functions in the body

Lithium has probably been used to treat mental illnesses since ancient times. Since the middle of the 20th century, it has been used primarily in the treatment of affective disorders (mania) and to prevent relapses in manic-depressive psychoses. From its effect, it is concluded that lithium functions in the central nervous system. Lithium probably plays a role in the transmission of the signal within the nerve cells after synaptic transmission. However, the exact mechanism of action of lithium is not fully understood. Lithium is also stored in the lymph nodes and in the skeleton, although its function is not known in detail here either.

Lithium-containing foods

Only traces of lithium are found in food. Significant amounts are found in some mineral waters and in drinking water. Other relatively good sources of lithium are meat, fish, eggs and dairy products, as well as some vegetables and cereals. For example, 100 g of meat contains around 100 µg of lithium.

Deficiency symptoms

It has not yet been satisfactorily clarified what effects an insufficient supply of lithium has. As lithium is used to treat mental illnesses, it is reasonable to assume that a deficiency could lead to psychological changes, e.g. aggressive behavior. However, there is not yet sufficient evidence for this.

Overdose and poisoning

An overdose, even with malnutrition, is not to be expected. A daily lithium intake of up to 10 mg is generally considered safe. However, very high doses of lithium are used to treat mental illnesses, which can sometimes lead to severe symptoms of poisoning if misused. Lithium poisoning can lead to nausea, vomiting, visual disturbances and apathy. Furthermore, kidney damage, cramps and even coma can occur. Treatment for acute poisoning consists of gastric lavage, increasing urine excretion with medication (forced diuresis) and, if necessary, hemodialysis, i.e. blood washing. An ECG (electrocardiogram) should also be carried out to check heart function.

Daily requirement

Depending on the author, the information on the daily requirement of lithium varies between 3 and 10 mg. There may be an additional requirement for mentally unstable people or mentally ill people, alcoholics and possibly immunocompromised people. This lithium requirement is only just covered by a normal diet.