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Copper is an important trace element that performs various functions in your body. It helps in iron absorption in the gut, synthesis of neurotransmitters and connective tissue and energy production in the body. Copper also helps in the proper functioning of the immune system, formation of new blood vessels and brain development. (Neurotransmitters are chemicals that the cells of our nervous system use to convey messages to each other and to the body.)

The human body cannot store large amounts of copper—an adult human has 50 mg to 100 mg of copper in their body, mostly in their muscles and bones. The rest of the copper is constantly excreted out through faeces and urine.

To maintain the levels of this mineral in your body, it has to be taken from food or in the form of supplements. However, excess copper can also be harmful to the body as it can increase your risk of liver damage. It can also cause gastrointestinal issues such as diarrhoea.

Here is all you need to know about copper, including the recommended daily requirement, the benefits, uses and side effects of copper and a list of foods from which you can obtain your daily dose of this mineral.

  1. RDA of copper: How much copper to take per day
  2. Copper rich foods
  3. Copper benefits and uses
  4. Deficiency of copper: why does it occur
  5. Copper side effects

The recommended daily allowance (RDA) of a nutrient is the amount you need to take daily to stay healthy. These requirements generally vary by age and gender, though for copper the requirements are the same in both genders in various age groups. 

The following is the RDA of copper for healthy people, according to the National Institutes of Health (NIH), US:

Age Recommended daily allowance
Babies up to 6 months 200 µg (microgram)
7 months to 1 year 200 µg
1 to 3 years 340 µg
4 to 8 years 440 µg
9 to 13 years 700 µg
14 to 18 years 890 µg
Adults above the age of 18 900 µg

Pregnant women should have at least 1000 µg (1 mg) of copper per day and breastfeeding women should take 1300 µg (1.3 mg) of copper every day.

A microgram is one-thousandth of a milligram.

According to the Office of Dietary Supplements, NIH, the average human diet can give you 1100-1400 µg of copper per day as this mineral is present in a wide range of animal and plant products.

The following are some foods that you can obtain copper from:

Copper is also present in tap water, especially in places with copper pipes. However, the amount of copper in water generally varies depending on the source of the water.

Copper supplements are rarely needed unless your doctor advises you to take them. Copper supplements are available along with multivitamin and multimineral tablets. These supplements contain various forms of copper, including copper sulphate, copper oxide, copper gluconate in different concentrations, ranging from a few micrograms to about 15 mg.

Copper is a cofactor of various energy-producing enzymes in the body. (A cofactor is something that needs to be present for a chemical reaction to take place.)

It plays an important role in iron metabolism and various other metabolic processes in the body. Here are some of the effects of copper on health:

Copper helps in energy production

Copper is a part of an enzyme called cytochrome C oxidase which is responsible for producing energy in the body.

Cytochrome oxidase is a part of the electron transport chain in the mitochondria membrane—every cell in the body has a powerhouse called mitochondria where glucose and oxygen are converted into energy in the form of ATP.

This enzyme helps generate electrical gradients across the membrane of the mitochondria, which, in turn, produces ATP, the energy currency of the cell.

Copper modulates the immune system

Our body needs copper for both the development and maintenance of the immune system. Though the exact mode of action of copper remains unknown, studies show that a deficiency of copper affects both our innate immunity (the one we are born with) and our acquired immunity (the one we develop after exposure to pathogens).  

A deficiency of copper can lead to a condition called neutropenia, which refers to the reduction in the number of neutrophils, a type of white blood cells. Copper deficiency has also been shown to reduce the function of neutrophils. Similar effects have been noted on macrophages in copper-deficient animals. Macrophages are immune system cells that engulf pathogens and destroy them.

Animal studies show that copper deficiency increases the risk of infection and mortality and mitigating the deficiency improves immune function. 

The effects of copper deficiency on macrophages and other immune system cells have also been shown in malnourished infants and copper-deficient adults in small-scale studies. (Read more: How to improve immunity)

Finally, copper is shown to play a role in the inflammation process. The levels of copper are seen to increase in the body during active inflammation. Inflammatory cytokines are suggested to be copper-dependent. (Read more: Cytokine storm)

Copper has antibacterial effects

Apart from helping the immune system to fight harmful microbes, copper also plays a direct role in fighting pathogenic (harmful) bacteria that enter the body. 

It is suggested that the phagocytic cells use the antibacterial effects of copper to kill harmful bacteria. Our body uses the copper ions in cells as antioxidants to neutralise the free radicals formed during an infection. These radicals, if left as is, may damage body tissues. At the same time, copper depletes the antioxidants in the bacteria, which leads to bacterial death.

Additionally, copper also affects certain iron-dependent metabolic pathways in bacteria, which stop bacterial growth and kill them.

Read more: Bacterial infection symptoms

Copper helps in iron metabolism

Copper has an important role in iron metabolism. Copper affects iron metabolism at almost every level, starting with the absorption of iron from the gut, movement of iron from cells, synthesis of heme from iron and reuse of iron in reticuloendothelial cells.

Reticuloendothelial cells mainly include monocytes and macrophages—two types of white blood cells that are crucial for our immune system. These cells store all the extra iron in the body. They also play a role in breaking down red blood cells (RBCs) and recycling the iron present in them. 

Low copper levels may cause the body to absorb less iron, which can lead to anaemia. So when your iron levels go down, your body sends copper to various areas of your body to increase their iron levels.

Copper containing enzymes convert iron from its ferrous to ferric state so that it can be transferred to various areas of the body through the transferrin protein.

Copper is involved in the synthesis of heme through cytochrome oxidase. Heme is an iron-containing compound present in RBCs that binds to and carries oxygen and carbon dioxide. (Read more: What is haemoglobin?)

It is not just copper deficiency but also copper excess that affects iron metabolism. Excess copper can reduce iron reutilisation from reticuloendothelial cells.

Copper effects brain health

Various enzymes that are needed for brain function are dependent on copper. Copper is needed for the formation and maintenance of the myelin sheath in nerve cells. This sheath covers brain cells and helps in the quick transfer of signals through the brain. Copper is also needed for the synthesis of various neurotransmitters, chemical messengers in the brain.

Studies show that imbalance in copper levels may play a role in the pathogenesis of Alzheimer's disease. Alzheimer’s patients have a higher level of free copper in their serum as compared to healthy individuals. Copper is thought to play a role in the formation of brain plaques (a characteristic of Alzheimer’s) and increase oxidative stress in the brain leading to brain damage.

An excess of copper is also associated with prion diseases, as cellular prion protein is dependent on copper. Cellular prion protein (PRPC) plays an important role in reducing oxidative stress and transmembrane signalling between neurons. When PRPC converts into its PRPSC form, it leads to neurodegenerative prion diseases.

Additionally, Wilson’s disease and aceruloplasminemia (a genetic disorder marked by the absence of copper from blood and accumulation of iron in the brain) are associated with cognitive impairment and dystonia (repeated and involuntary contraction of muscles) like that in Parkinson’s disease. Copper is also associated with the pathophysiology of Parkinson’s, though the evidence is not clear.

Hence, copper balance is said to be highly important to maintain good brain health.

Copper effects bone health

Copper is involved in the development and maintenance of bones. Copper deficiency is associated with decreased bone mineral density and increased risk of bone fractures

Copper deficiency is the cause of osteoporosis in people with Menkes disease. Menkes disease is a genetic disorder which occurs due to mutation in a gene—ATP7A—which is involved in the regulation of copper levels in the body. Low copper levels in those with Menkes leads to other problems such as kinky hair and nervous system dysfunction.

A study done in 11 healthy men showed that intake of about 0.7 mg of copper per day was found to improve bone resorption within six weeks.

In a randomized double-blind study, postmenopausal women were found to have less bone loss when given copper, zinc, and manganese supplements. 

According to a study published in the journal Osteoporosis International, copper deficiency also causes wearing down of teeth enamel in adults. Though the exact mode of action is still unknown.

Now you know about some of the effects of copper deficiency and excess in the body. This section includes some of the causes of copper deficiency.

Copper deficiency may be acquired or it may be inherited. Inherited copper deficiency is called Menkes disease. It is an X linked genetic disorder that shows up in about one in 100,000 to 250,000 male births. Most of the children born with this deficiency die by the age of 10 years. Some symptoms of Menkes disease include:

Acquired copper deficiency occurs due to one of the following: 

  • Excessive intake of zinc
  • Malnutrition, especially less intake of protein in infants (Read more: Best foods for 7- to 9-month-old baby)
  • Conditions like Celiac disease that affect the absorption of nutrients in the gut
  • Those who have had a gastric bypass may develop copper deficiency
  • Those who are on parenteral nutrition (intravenous or IV feeding) and are not taking enough copper

Despite its many health benefits, copper can be harmful if taken in excess. Here are some of the harmful effects that excessive copper can exert on your body:

Since the human body expels most of the extra copper, healthy people rarely get toxicity from this mineral. However, those with Wilson’s disease, a hereditary disorder characterised by the build-up of copper in the body, are at risk of copper toxicity. Also, infants and newborns are at a higher risk of developing copper toxicity since their body absorbs a lot of nutrients from the intestines. 

Here is the upper limit of copper intake for every age, as per the NIH:

Age Upper limit
Up to 6 months Not known/established
7 months to 1 year Not known/established
1 to 3 years 1000 µg
4 to 8 years 3000 µg
9 years to teenage 5000 µg
14 to 18 years 8000 µg
Adults above the age of 18 10000 µg

The daily upper limit of copper intake in pregnant women is set at 8000 µg (8mg) and in lactating women, it is 10000 µg.

References

  1. MedlinePlus Medical Encyclopedia [Internet]. US National Library of Medicine. Bethesda. Maryland. USA; Copper in diet
  2. National Institute of Health. Office of Dietary Supplements [internet]: Bethesda (MA), US. US Department of Health and Human Services Copper
  3. University of Illinois [Internet].University of Illinois at Urbana-Champaign. Illinois. US; Cytochrome oxidase
  4. Stabel Judith Reffett, Spears Jerry W. Effect of Copper on Immune Function and Disease Resistance, In: Kies C. Copper Bioavailability and Metabolism. Springer, Boston, MA. Springer-Verlag US 1989. pp: 243-252.
  5. Djoko Karrera Y., Ong Cheryl-lynn Y., Walker Mark J., McEwan Alastair G. The Role of Copper and Zinc Toxicity in Innate Immune Defense against Bacterial Pathogens. J Biol Chem. 2015 Jul 31; 290(31): 18954–18961. PMID: 26055706.
  6. Linus Pauling Institute. Micro nutrient Information Center: Oregon State University, Corvallis, Oregon; Copper
  7. Hordyjewska Anna, Popiołek Łukasz, Kocot Joanna. The many “faces” of copper in medicine and treatment. Biometals. 2014; 27(4): 611–621. PMID: 24748564.
  8. Chan Wai-Yee, Owen M. Rennert. The Role of Copper in Iron Metabolism. Annals of clinical and laboratory science. 1980; 10(4): 338-344.
  9. Knutson M, Wessling-Resnick M. Iron metabolism in the reticuloendothelial system. Crit Rev Biochem Mol Biol. 2003;38(1):61-88. PMID: 12641343.
  10. Doguer Caglar, Ha Jung‐Heun, Collins James F. Intersection of Iron and Copper Metabolism in the Mammalian Intestine and Liver. Comprehensive Physiology. 2018; 8(4).
  11. Esterbauer H, Wäg G, Puhl H. Lipid peroxidation and its role in atherosclerosis. Br Med Bull. 1993;49(3):566-576.PMID: 8221023.
  12. Mylonas C, Kouretas D. Lipid peroxidation and tissue damage. In Vivo. 1999;13(3):295-309. PMID: 10459507.
  13. American Heart Association [internet]. Dallas. Texas. U.S.A.; Atherosclerosis
  14. Bagheri Babak, Akbari Negin, Tabiban Sasan, Habibi Valiallah, Mokhberi Vahid. Serum level of copper in patients with coronary artery disease. Niger Med J. 2015 Jan-Feb; 56(1): 39–42. PMID: 25657492.
  15. Westergard Laura, Christensen Heather M., Harris David A. The Cellular Prion Protein (PrPC): Its Physiological Function and Role in Disease. Biochim Biophys Acta. 2007 Jun; 1772(6): 629–644. PMID: 17451912.
  16. Montes Sergio, et al. Copper and Copper Proteins in Parkinson’s Disease. Oxidative medicine and cellular longevity. 2014; 2014(147251).
  17. Qu Xinhua, et al. Serum copper levels are associated with bone mineral density and total fracture. J Orthop Translat. 2018 Jul; 14: 34–44. PMID: 30035031.
  18. Genetics Home Reference [internet]. National Institute of Health: US National Library of Medicine. US Department of Health and Human Services; Menkes syndrome
  19. Della Pepa Giuseppe, Brandi Maria Luisa. Microelements for bone boost: the last but not the least. Clin Cases Miner Bone Metab. 2016 Sep-Dec; 13(3): 181–185. PMID: 28228778.
  20. Sierpinska T., Konstantynowicz J., Orywal K., Golebiewska M., Szmitkowski M. Copper deficit as a potential pathogenic factor of reduced bone mineral density and severe tooth wear. Osteoporos Int. 2014; 25(2): 447–454. PMID: 23797848.
  21. Merck Manual Professional Version [Internet]. Kenilworth (NJ): Merck & Co. Inc.; c2019. Copper Deficiency
  22. Hicks Faith, Mirchandani Divya, Blanchard Samra Jr., Malkani Anjali. Acquired Copper Deficiency: Prolonged Jejunal Nutrition Support in a Child. The American Journal of Gastroenterology. 2016; 111(pS971).
  23. University of Rochester Medical Center [Internet]. Rochester (NY): University of Rochester Medical Center; Copper
  24. Collins James F. Copper. Adv Nutr. 2011 Nov; 2(6): 520–522. PMID: 22332094.
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