In 1982, the US Mint radically changed the makeup of the penny, from 95% copper all the way down to 2.5%. The reason? Copper had become so expensive that the metal in the coins was worth more than the face value, leading people to hoard them in the hopes of turning a profit.
Prices for copper rose in the 1970s largely due to the electronics revolution. Copper is a great conductor of electricity. So as the need for wiring and components increased, global demand did, too.
Copper’s properties also make it not just valuable but indispensable for human health. It doesn’t get the same press as other minerals, such as calcium and iron. But it serves many crucial functions in the body.
In this article, we’ll explore why copper is necessary for bodily functions ranging from immune support to antiaging properties to brain protection. We’ll discuss the potential risks of not getting enough copper, and whether that’s a concern (especially for plant-based eaters), as well as the very real dangers of getting too much copper.
What Is Copper?
Copper is an essential trace mineral found in every tissue of your body. Like other minerals, your body doesn’t make its own; you need to get it from food. But compared to many other essential minerals, you don’t need a lot for optimal functioning.
Copper is a very busy do-gooder in your body, lending a hand all over the place. It’s a cofactor (a nonprotein molecule that supports a biochemical reaction) for several enzymes known as cuproenzymes (“kupros” is Greek for copper, so named because the island of Cyprus was famous for its rich copper deposits). These enzymes are involved in the production of energy, neurological signaling, and the making of connective tissue.
Copper helps your body form collagen and assists in iron absorption. It also acts as an antioxidant. The main defense against oxidative stress actually involves copper-based compounds called superoxide dismutases (SODs for short). SODs help convert superoxide radicals into less harmful molecules like oxygen and hydrogen peroxide.
Copper is also involved in the formation of new blood vessels. Plus, it helps balance various neurohormones, regulates gene expression, supports brain development, influences skin pigmentation, and maintains the functioning of the immune system. That’s one busy mineral!
How the Right Amount of Copper Benefits Your Health
Copper is essential for many bodily processes but harmful in both deficiency and excess. (Or as Goldilocks might say, “Not too little and not too much, but just right.”) Maintaining appropriate copper levels is important for overall well-being. And it’s particularly important for the health and functioning of your brain, bones and joints, heart, arteries, skin, and immune system.
Let’s look at some of the ways that researchers study copper in regard to health.
Copper and Heart Health
Proteins containing copper are essential for protecting your cardiovascular system from stroke and the damage it can cause. When the body doesn’t manage copper levels properly, it can lead to heart problems, including enlargement, heart failure, coronary artery disease, and a type of heart disease related to diabetes.
But for most people, too much copper is a more likely problem than not getting enough. A 2015 study compared copper levels in 334 people, some of whom had healthy arterial function and some with varying degrees of atherosclerosis (arterial hardening and blockages). Researchers found higher blood levels of copper in the patients with atherosclerosis. And the more severe the condition, the higher the levels of copper.
Because of the study design, we can’t say whether the high copper levels caused the atherosclerosis or if it was the other way around. (Or, for that matter, if both stem from something else.)
Copper and Brain Health
The right amount of copper is also necessary for brain development and function. Diseases that affect brain copper levels, such as Menkes disease (not enough copper) and Wilson disease (too much copper), affect the functioning of neurotransmitters called catecholamines. They play a role in various brain functions, such as regulating mood, motivation, attention, and stress response. And they’re involved in transmitting signals between neurons and can affect cognition and behavior.
Elevated copper levels may also play a role in the development of Alzheimer’s disease. Studies have shown high levels of copper can affect the functioning of neurons in important areas of the brain, such as the hippocampus and cerebral cortex. This can lead to problems with memory, critical thinking, and motor skills.
Researchers have also discovered a connection between copper and the formation of amyloid beta plaques, which are a hallmark of Alzheimer’s disease. As copper levels increase, it can speed up the formation of these plaques, contributing to further damage in the brain.
Copper and Bone Health
Too much or too little copper is also a problem for your bones and joints. Copper compounds are important cofactors for an enzyme that makes bone matrix (basically, the stuff that makes up your bones). And nearly two-thirds of the copper in your body is stored in muscles and bones.
In 2014, researchers looked at 50 adults who had severe tooth wear (that means their teeth were worn down, not that their teeth wore high-necked cardigans and ankle-length skirts). They found lower copper levels in their tooth enamel, as well as lower bone mineral density in the spine, which is a predictor of osteoporosis.
A 2018 study measured copper levels in participants’ blood and also looked at several aspects of bone health, including bone mineral density and whether they had fractured any bones. Researchers found that people with lower levels of copper had lower bone mineral density in certain areas of the hip compared to those with slightly higher levels of copper.
They also found that those with very high levels of copper in their blood had a higher risk of experiencing fractures compared to those with slightly lower levels. So again, copper adheres to the Goldilocks principle.
Copper and Skin Health
It’s time to introduce you to a very special substance in your blood: glycyl-L-histidyl-L-lysine. That’s a mouthful, so we’ll follow the scientists in calling it GHK.
GHK levels are highest when you’re young, around 20 years old, but decrease as you get older. By the time you’re 60 years old, the levels drop significantly.
GHK has a special attraction to copper, and when they come together, they form something called GHK-Cu. GHK-Cu can help rejuvenate your skin by promoting the growth of new skin cells and speeding up the healing process. It has powerful antioxidant properties, which means it helps protect your skin from the sun and other oxidative damage. And it can also reduce inflammation in the skin, which can help prevent and smooth out wrinkles.
Did you know your skin can absorb copper? Studies show that there’s a low risk of adverse reactions from skin absorption of copper. And several placebo-controlled clinical trials have shown that sleeping on pillowcases impregnated with copper oxide can actually reduce the depth of facial wrinkles and improve overall skin health.
A 2020 study took small skin grafts and exposed them to these fabrics. The researchers found that they continuously released copper ions that were absorbed through the skin, which increased the production of some skin proteins, stabilized the dermal layer, and reduced aging and damage.
Copper and the Immune System
Copper is also required for the formation and activity of neutrophils, a type of white blood cell that’s a key component of the immune system. Their main role is to defend the body against infections caused by bacteria and fungi.
But there’s a downside to copper’s ability to support immunity: There’s an association between excess copper levels and increased immunity of cancerous tumors to treatment. So how difficult is it to get the right amount of copper for good health?
How Much Copper Do You Need?
Since copper is a trace nutrient, only a small amount is necessary daily. And only a small amount is stored in the body. Whereas iron or calcium requirements are in milligrams per day (mg/day), copper needs are in micrograms per day (mcg/day). A microgram is one-millionth of a gram, which is a very, very tiny amount indeed.
The following are the United State’s RDAs (Recommended Daily Allowances) for copper at different stages of life.
So those are the recommended minimum levels. What about maximums? Officially, the upper limit of copper for adults is 10,000 mcg per day. But it may also be the case that the official maximum levels should be lower. As many scientists are fond of saying, “More research is needed.”
Dietary Copper Sources
Copper is in a variety of foods. And the foods highest in copper are animal-derived products such as organ meats, oysters and other seafood, poultry, and red meat. Meat products are the only foods that will put you anywhere near the upper limit of 10,000 mcg per day. For example, three ounces of pan-seared beef liver has over 12,000 mcg of copper.
But you don’t have to eat animal products to meet your RDA of copper. Many plant-based foods are good sources of copper, too.
Here are some of the top plant-based sources of copper:
If clinical copper deficiency is present, symptoms can include anemia (not enough red blood cells and/or not enough hemoglobin in the blood), bone and connective tissue abnormalities, and neurological problems.
But since so many foods contain copper, deficiency is generally less about intake and more frequently due to intestinal problems (such as Celiac disease) or genetic conditions. Maintaining adequate copper levels in the body is mostly dependent on absorption from the intestines. As a result, copper deficiency is relatively uncommon among the general population.
Your body also has the ability to modulate its copper absorption rate based on availability. It generally increases the absorption rate if your diet contains less copper.
However, copper levels are not typically assessed in routine testing as there isn’t a reliable biomarker for copper status. Blood levels of copper and ceruloplasmin (CP) concentrations are sometimes used in people with a known deficiency (such as with Menkes disease). But factors such as infection, pregnancy, and even some cancers can affect the accuracy of these levels.
Zinc Supplementation and Copper
However, there’s a cause of copper deficiency that is in your control and has been seen more frequently since the start of the COVID-19 pandemic: zinc supplementation. Zinc was one of many dietary supplements recommended during the height of the pandemic as a means to bolster immune defense.
While zinc can help prevent and fight infections, there is the issue of too much of a good thing. Excessive zinc intake (more than 50 mg a day) has been shown to interfere with the body’s absorption of available copper. As a result, copper levels in the body can drop to dangerous levels and cause symptoms of deficiency.
High doses of vitamin C (over 1,500 mg a day) or supplemental iron may also induce copper deficiency by competing with copper for absorption in the intestine. This is one reason to be cautious about taking large amounts of supplements on an ongoing basis.
There are also a few ways to have dangerously high levels of copper in your body. That condition is most frequently associated with Wilson disease, a rare inborn error of metabolism that starts by overloading the liver with copper, and then moves on to the brain and other tissues.
People can also get acute copper poisoning from drinking beverages stored in copper-containing containers, as well as from contaminated water supplies. The US Environmental Protection Agency has set upper limits on copper in drinking water at 1.3 milligrams per liter, while the World Health Organization is okay with the slightly more lenient 2 milligrams per liter.
Copper can enter your drinking water through corroded copper pipes, so if you live in an old house or have well water, you may want to get your water tested.
Excessive amounts of copper can cause abdominal pain, nausea, vomiting, and diarrhea in the short term. Long-term copper overexposure can cause liver damage and kidney failure.
You can also get copper poisoning by cooking food, especially acidic food like tomato sauce, in uncoated copper cookware. (Many chefs love this cookware because copper is an excellent conductor of heat.) The good news is, most copper cookware is lined with a nonreactive metal, such as nickel, tin, or stainless steel. As long as you take care of the lining by cleaning it with nonabrasive materials, and stop using it if the lining starts to crack or flake, copper cookware can be perfectly safe.
Toxicity from Copper Supplementation
Another cause of copper toxicity is taking copper-containing supplements. Some of the most commonly found multivitamins contain copper. And some even contain over double the RDA for copper. But copper supplementation is not generally recommended.
Health care professionals like Dr. Neal Barnard actually advise against the inclusion of both iron and copper in multivitamins. Too much of either can negatively impact brain health, possibly even contributing to the development of neurological disorders like Alzheimer’s and Parkinson’s. One 2022 study based on the Atherosclerosis Risk in Communities (ARIC) cohort found that “Copper intake from supplements was associated with greater 20-year decline in global cognition overall.”
However, the amount of copper in multivitamins and other supplements isn’t the only reason there’s a risk of toxicity. It’s also because the average copper intake among US adults already exceeds the recommended amounts. With so many foods providing an abundance of copper, especially animal products that are commonly consumed as part of the modern industrialized diet, there’s no need for added copper supplementation.
In fact, getting copper from animal products may be just as bad or even worse than getting it from supplements. That same 2022 study found that dietary copper, especially when consumed with saturated fat, increased the risk of incident dementia. And since plant-based foods have lower copper bioavailability and saturated fat, there’s no known neurodegenerative effects (and less risk of copper toxicity).
Copper-Rich (But Not Copper-Excessive) Plant-Based Recipes
Goldilocks would be happy with these tasty (and simple to prepare) plant-based recipes. From savory breakfast wraps to naturally sweet chocolate chip muffins, meeting your copper needs (without risking exceeding them) on a plant-based diet can be easy (and delicious)!
Tofu Scramble Breakfast Wrap is a delicious morning meal that not only satisfies your taste buds but also prioritizes your nutritional well-being. You’ll get your daily copper needs met from the tofu, spinach, and avocado in this wrap. Plus, you also get the added benefits of fiber, plant-based protein, healthy fats, and plenty of other essential nutrients. This wrap is a hearty and savory way to start your day the plant-based way!
Green Goodness Sandwich practically overflows with fresh, colorful, and nutrient-rich veggies. The green veggies — leafy greens, cruciferous vegetables, and avocados — are all great sources of plant-based copper. And this sandwich is also piled high with other colors (which means lots of phytochemicals!) — from red tomatoes to purple onion to orange turmeric to white seeds. This nourishing meal is bursting with so much wholesome goodness, you may want to add it to your regular recipe rotation.
Dark chocolate and millet are the copper-rich, plant-based stars of these Banana Chocolate Chip Millet Muffins. Whether you enjoy the muffins as a wholesome breakfast or an afternoon pick-me-up, you can take pleasure in knowing that you’re getting the nutrients your body needs. Indulge in the delightful flavor and nutritional benefits of Banana Chocolate Chip Millet Muffins — because a little copper can go a long way toward a healthier you!
Getting the Right Amount of Copper is Key
Although it doesn’t get the same attention as many other nutrients, copper is essential to health and vitality. It works as an antioxidant — combatting oxidative stress throughout your body. And it has research-backed benefits for your heart, brain, bones, skin, and immune system.
But too much copper can be a problem, and this may be more of a concern for people who eat large amounts of animal products that are especially high in it, take supplements with copper, or whose drinking water is contaminated with copper from pipes. The good news is that it seems most people who eat a plant-based diet will do just fine with their copper consumption. And that should please Goldilocks very much.
Tell us in the comments:
Penny for your thoughts! What did you find surprising about copper and nutrition in this article?
What’s your favorite copper-containing plant-based food?
Which recipe will you try next?
Featured Image: iStock.com/ratmaner