If you take zinc supplements, you need to pay extra attention to copper. Balanced copper intake supports immunity, helping to prevent infection; too little or too much copper leads to inflammation. Research also reveals that coronavirus can’t survive long on copper surfaces. Find out all the reasons why copper is worth talking about amid the COVID-19 pandemic.
This article is for informational purposes only. The current coronavirus outbreak is an ongoing event and certain details may change as new information comes to light. No effective or FDA-approved products are currently available for the treatment of the new coronavirus (also known as SARS-CoV-2 or 2019-nCoV), although research is still ongoing. For now, the best preventive measures you can take against COVID-19 are standard precautions, including social distancing, hand washing, and avoiding touching your face.
Is Copper Important Amid the COVID-19 Pandemic?
Copper (Cu) is an essential trace mineral. Among other roles, copper supports a healthy immune response and antioxidant defense [1, 2, 3].
Most people get enough copper and don’t need to supplement. However, copper has to be balanced with zinc in the body [4, 5].
Since some people are turning to zinc as an immune booster amid the COVID-19 pandemic, copper deserves special attention. If you are taking a zinc supplement, you need to make sure you are also getting enough copper to avoid deficiency.
Copper is not just a dietary nutrient, it’s also traditionally melted into alloys to make kitchenware, furniture, and even coins. Research shows that the new coronavirus dies faster on copper surfaces compared to materials like wood and plastic [6].
Copper, Immunity & Inflammation
Supports Immune Health
Copper deficiency weakens the immune response. People with weakened immune systems are at an increased risk of infectious diseases, and coronavirus is no exception [7].
People with copper deficiency are more likely to have low neutrophils (neutropenia), white blood cells that help kill invading microbes [8, 9].
On the other hand, copper deficiency can over-activate neutrophils and cause them to build up in the liver, which contributes to inflammation [10, 11, 12, 13].
Additionally, copper deficiency can disrupt immune cells called macrophages, additionally increasing susceptibility to bacterial infections [14, 15].
Mixed Effects on Inflammation
Inflammatory mediators called cytokines are a double-edged sword in COVID-19 [16].
By boosting the immune system, cytokines might reduce susceptibility to infection or help fight the virus off in the early stages.
However, coronavirus can hijack the immune system, sending it into overdrive. In severe COVID-19, mass-produced cytokines wreak widespread inflammation and serious organ damage [17, 16, 18].
Overall, copper is anti-inflammatory when in balance. Both copper deficiency and excess can lead to inflammation [19].
Ceruloplasmin is a protein that carries copper in the blood. It might alter the effects of copper supplementation on immunity and inflammation [20, 21].
In a study of 33 volunteers, copper supplements increased IL-2 in people with normal-low ceruloplasmin. IL-2 is an immune-stimulating compound that belongs to the cytokine family; it helps balance the immune system, increasing immune defense while preventing autoimmunity [20, 21].
Importantly, copper supplements don’t seem to affect TNF-alpha, a different purely inflammatory cytokine [20].
Too much copper can have the opposite effect. High copper levels may increase the production of free radicals, which results in tissue damage and inflammation [22, 23].
The impact of copper supplements on inflammation in COVID-19 has yet to be explored.
During cholera epidemics in the 19th century, scientists observed that workers exposed to copper salts did not develop cholera [24].
Later on, many studies explored the potent antimicrobial properties of copper. Nowadays, copper is used as a “biocide” in agriculture, wood preservation, paints, and in hospitals [25, 26, 27, 28].
According to one cell-based study, ionic copper may weakly block papain-like protease-2, a protein that SARS-CoV requires to multiply. Ionic zinc can also block this protein, but at much lower levels than copper [29].
The Severe Acute Respiratory Syndrome coronavirus (SARS‐CoV) was first identified in 2003. It is different from the new coronavirus that is behind the current pandemic [7].
It’s theoretically possible that copper may target the same proteins in the new coronavirus, but this has yet to be tested.
Copper might also turn out to be a great material for hospital equipment and surfaces. On surfaces made from alloys of copper, silver, and aluminum, SARS-CoV survives for less than five minutes. In comparison, most coronaviruses survive for 4-9 days on other surfaces like glass, plastic, Teflon, wood, and stainless steel [30, 31].
How does the new coronavirus hold up?
A recent study suggests that SARS-CoV-2 (the new coronavirus) is more resilient, but it’s not resistant to copper. The virus was detectable for up to 4 hours on copper surfaces, which is pretty good compared to other materials. For example, the new coronavirus was detected for up to 24 hours on cardboard and up to 2 to 3 days on plastic and stainless steel [6].
Another coronavirus strain that rarely causes serious infections (human coronavirus 229E) is much more sensitive: it dies in under 30 minutes on materials that contain at least 70% copper. Increasing copper concentrations seem to kill it even faster. Scientists suspect that copper triggers extreme oxidative stress in the virus, causing it to die off [32].
Brass is another promising material. It is an alloy of zinc and copper that seems to be effective even though it’s lower in copper. Researchers point out that zinc alone hardly had any effect, suggesting that it only boosts the effects of copper when coronavirus comes into contact with it on inanimate surfaces [32].
Copper-based materials are no new technology. People around the world have long used copper vessels for cooking and water storage. Copperware has fallen out of favor in modern times, but it might see a huge revival as new coronavirus research comes out.
However, findings about copper alloys can’t be applied to copper supplements and the human body. The amount and type of copper needed to kill coronavirus in the mouth, throat, and lungs are unknown. It may well be above the safe levels humans can tolerate.
Chronic diseases — particularly heart disease, lung diseases, and diabetes — are big risk factors for COVID-19 complications and death [17].
Here’s an overview of how copper may affect some of these systems in the body:
Heart Health
COVID-19 can cause severe heart damage in hospitalized patients. Meanwhile, high blood pressure and heart disease are among the biggest risk factors for COVID-19 complications and death [33, 34].
The impact of copper on these complications is unknown. However, we do know that copper is essential for the strength and integrity of the heart and blood vessels. Low copper has been linked with high blood pressure [35].
Copper supplementation improves heart function and helps reverse heart enlargement caused by copper deficiency, according to studies [36, 37, 38, 39, 40, 41].
In 16 healthy young women, copper supplementation reduced one marker associated with clogged blood vessels or atherosclerosis (plasminogen activator inhibitor-1) by 30% [42, 43].
In rats, copper decreased blood levels of total cholesterol, triglycerides, and “bad” LDL-cholesterol while slightly increasing “good” HDL-cholesterol. A clinical study confirmed these findings in 73 patients, of which 28 were copper-deficient [44, 45].
Are You At Risk Of Deficiency?
Most people get enough copper from diet, supplements, and water. Copper deficiency is rare and usually only occurs in seriously ill people receiving intravenous (parenteral) nutrition that lacks copper [46, 47].
Other groups at risk of copper deficiency include:
- Newborns (preterm, recovering from malnutrition, fed only cow’s milk formula, with prolonged diarrhea, with cholestasis) [48, 49, 50, 51]
- People who use zinc supplements or zinc-enriched dental creams [13, 52]
- Pregnant and breastfeeding women [53]
- People with gut disorders that impair nutrient absorption, including Crohn’s disease, celiac disease, and short bowel syndrome [54, 55, 56]
- Cystic fibrosis patients [57]
- People with high blood pressure [35]
Doctors give copper by mouth or through an IV to treat copper deficiency [46, 47].
Dosage & Precautions
Dosage
The Recommended Dietary Allowance (RDA) for copper is [58]:
- Children: 0.3 – 0.9 mg/day (depending on age)
- Adults: 0.9 mg/day
- Pregnancy and breastfeeding: 1 – 1.3 mg/day
The average adult in the United States gets about 1.0 to 1.6 mg/day.
The Tolerable Upper Intake Level is 10 mg/day. This is the highest daily intake that is likely to pose no health risk for most people [58].
Interaction with Zinc
Zinc supplements can reduce copper levels. That’s because zinc increases metallothioneins, proteins that bind copper and prevent its absorption.
Copper deficiency has been reported in people taking higher doses of zinc-only supplements or using zinc-based dental creams in excess [59, 60, 52].
To reduce the risk of copper deficiency, most zinc-copper supplements provide 1 mg of copper for every 10-20 mg of zinc.
If you take a zinc supplement that does not contain any copper, you should ensure to get adequate amounts of copper every day. For example, if you take 15 mg of zinc per day, you should aim for about 1.5 mg of copper.
Food Sources
Copper-rich foods include [61, 62, 63]:
- Liver (especially calf, lamb, beef)
- Seafood (oysters, squid, lobster, crab)
- Fruit and vegetables (dark leafy vegetables, potatoes, mushrooms, avocados, dried fruit)
- Seeds (sesame, sunflower, pumpkin)
- Nuts (cashew, hazelnuts, Brazil nuts, walnuts)
- Beans (chickpeas, soybeans, adzuki)
- Dark chocolate and cocoa
Oysters are also high in zinc, making them a good source of both nutrients.
Precautions & Side Effects
Supplements that contain adequate daily doses of copper are likely safe for healthy people, including children and pregnant women. Make sure not to exceed the safe upper limit of 10 mg/day [64].
Copper supplements should be avoided in people with the following genetic disorders affecting copper metabolism:
Ingesting more than 1 g of copper can cause toxicity; this is a rough threshold that depends on individual factors [68].
Takeaway
Balanced amounts of copper support immune health. Copper deficiency can lead to inflammation and poor immune function, which can make COVID-19 more serious.
Luckily, most people get enough of this mineral from food and water. People who take zinc supplements, suffer from gut disorders, or have life-threatening diseases may require copper supplements.
High levels of copper, which are dangerous for humans, might directly kill coronavirus. High-copper materials hold promise for killing and reducing the spread of coronavirus. Surfaces made from copper alloys like brass seem to kill coronavirus in up to 4 hours, but more research is needed.
