Once introduced with the foods that contain it, the copper is absorbed in the small intestine and from here, thanks to the bond with the albumin, it is conveyed to the liver. The hepatocytes in turn synthesize a complex consisting of copper and its transporter (celuroplasmin), which is then secreted to be distributed to the various tissues. Any excesses are eliminated mainly by the biliary route and minimally excreted in the urine.
Thanks to its ability to pass from the reduced (Cu +) to the oxidized (Cu2 +) form, copper enters numerous metabolic pathways that require redox intervention. Its action is important for the mineralization of the skeleton and for the formation of new red blood cells and connective tissue. Copper also participates in the respiratory chain, in the synthesis of melanin and in protective systems against oxidative stress and the excess of biogenic amines.
The copper requirement for the adult Italian population was set at 1.2 mg per day; only for nurses this quota rises to 1.5 mg / day. The foods richest in copper are: some offal and fishery products - such as molluscs and crustaceans - but also cocoa, oilseeds or dried fruit, cereal germ and bran.
Since these foods are quite common in the human diet, there is no real danger of running into syndromes associated with copper deficiency. However, some cases have occurred in infants subjected to severe states of malnutrition, in premature infants kept on a milk diet and in patients fed for a long time exclusively by parenteral route. The associated symptoms include bone mineralization problems up to osteoporosis, anemia, skin and hair depigmentation, increased susceptibility to infections, vascular and skin fragility.
In some cases a dose of "only" 30 g of copper sulphate proved lethal; in any case, the assumption of these quantities, by mistake or for suicidal purposes, has a powerful emetic effect that favors a rapid elimination of excesses through vomiting. Symptoms associated with severe systemic intoxication include coma, oliguria, hepatic necrosis, collapse and The American institutes (Food and Nutrition Board 2001) have set the toxicity threshold at 10 mg / day; cases of intoxication due to diet alone are however extremely rare.
For more information see the article: Copper.
- shellfish - especially crabs and lobsters
- shellfish - especially oysters
Other food sources that contain copper are:
- sweet fruits - such as lemons and grapes, especially raisins or raisins, but also coconut, papaya and apples
- tubers - especially potatoes
- other legumes - such as peas
- mushrooms
- brewer's yeast
- meats - especially lamb, duck, pork and beef
- dark green leafy vegetables - for example, black cabbage.
Even if they are not particularly rich, if consumed in significant quantities, tea, polished rice and chicken meat also favor the achievement of the needs.
To avoid copper deficiency it is generally sufficient to respect a balanced diet, or at least to vary the range of foods without excluding any of the VII fundamental groups. With a normocaloric diet, even in developing countries - based mainly on millet, tubers or rice, associated with legumes or small quantities of fish or meat, certain fruits and vegetables, and some vegetable oils - it is very likely that the intake copper is adequate. The copper intake seems adequate even in countries where the diet consists mainly of red meat.
As a natural element in the earth's crust, copper is present in most of the world's surface and groundwater, although the actual concentration varies greatly depending on the geographic area.
In many regions of the world, copper pipes carrying drinking water are a real source of food copper. Copper pipes can release a small amount of metal, particularly in the first two years of service. "Inside the copper pipes, a protective surface is usually formed which delays corrosion.
Drinking water can contribute 20-25% to the daily copper intake.
copperCopper supplements can prevent copper deficiency, but should only be taken under the supervision of a doctor. In fact, the different forms of copper integration have equally different absorption rates. For example, copper absorption from cupric oxide supplements is lower than that from gluconate, sulfate or copper carbonate products.
For healthy adults eating a balanced diet including a wide range of foods, supplementation is generally not recommended. However, under medical observation, copper supplementation may be necessary for premature infants, for those with low weight at the time. birth, for children fed with unbalanced formulas during the first year of life and for malnourished children in general.
More generally, doctors may consider copper supplement in the following cases:
- diseases that reduce digestion - for example children with frequent diarrhea or infections, alcoholics etc.
- insufficient diet - for example the elderly, sick with eating disorders or following extraordinary restrictions
- taking drugs that block the metabolic use of copper in the body
- anemia treated with iron supplements
- taking zinc supplements
- osteoporosis.
Many vitamin supplements contain copper in inorganic form, such as cupric oxide. These supplements can cause excess free copper in the brain because, in inorganic form, it can cross the blood-brain barrier directly into nerve tissue.
Normally, on the other hand, the organic copper in food is first absorbed, then processed by the liver and finally conveyed into the blood by means of transport proteins, phases that allow you to keep circulating free copper levels under control and prevent what happens with inorganic copper.
; Roy, A; Yonone-Lioy, MJ; Opiekun, RE; Lioy, PJ. "Environmental copper: its dynamics and human exposure issues". Journal of Toxicology and Environmental Health. Part B, Critical Reviews. 4: 341–94
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