What is nickel?
Nickel is an element present in organisms in an amount equal to about 1 mg total, mostly distributed between the bones, pancreas and saliva. The minerals from which most nickel is extracted are iron/nickel sulfides such as pentlandite It is used for increasing iron absorption, preventing iron-poor blood (anaemia) and treating weak bones. Humans may be exposed to nickel by breathing air, drinking water, eating food or smoking cigarettes. Skin contact with contaminated soil or water may also result in nickel exposure. While nickel is an essential element and performs a vital function in metabolism, too much intake can prove dangerous to human health.
What is the function of nickel?
Nickel acts as a cofactor for several enzymes. Research conducted in humans and animals indicates a role in the metabolism of certain hormones, as well as glucose and lipids. Also, it seems that nickel is involved in maintain the integrity of cell membranes and the stability of DNA and RNA.
Which foods are rich in nickel?
Nickel is present in grains, seeds, buckwheat and seafood. Cabbage, tomatoes, beans and other legumes can be a source of this element as well. In general, it is worth noting that the amount of nickel naturally present in foods of plant origin depends greatly on the ground on which they were grown. Chocolate is included among the one of the main sources of nickel. Higher amounts are found in hydrogenated vegetable fats, as nickel is used for their production.
What is the recommended daily requirement of nickel?
The human body requires about 100 micrograms of nickel per day.
What are the consequences of nickel deficiency?
Generally, the demand for nickel is completely satisfied by supply. There are, however, a few conditions (such as excessive sweating, intestinal malabsorption, stress or diseases such as cirrhosis and chronic renal failure) that may lead to deficiencies. These deficiencies in turn can cause liver failure, growth problems and reproductive problems, discoloration of the skin and worsening of pre-existing anaemia.
What are the consequences of excessive nickel intake?
Excess of nickel that accumulates in the liver, kidneys, bones and the aorta can lead to poisoning. Possible symptoms may include nausea and vomiting, headache, dizziness, difficulty breathing, coughing, chest pain, and skin rash. A relatively high intake of nickel has also been associated with an increased risk of certain cancers, such as lung, nose, larynx and prostate cancer, as well as heart attack, stroke, asthma, chronic bronchitis, and respiratory failure. Exposure to nickel and its compounds may result in what is known as “nickel itch”. It is generally the first symptom, which can be persist and worsen, causing skin ulcerations if not properly treated.
