20 Foods High in Copper: Best Sources for Energy, Iron Metabolism, and Antioxidant Defense

Copper is a trace mineral that quietly drives some of the most essential reactions in human biochemistry. It serves as a cofactor for more than a dozen critical enzymes, including cytochrome c oxidase, the final enzyme in the mitochondrial energy chain that produces ATP; ceruloplasmin, the protein that mobilizes iron from storage and enables red blood cell formation; superoxide dismutase, one of the body’s primary antioxidant enzymes; and dopamine beta-hydroxylase, which converts dopamine to norepinephrine and directly affects mood, energy, and focus. Copper is also required for collagen cross-linking through lysyl oxidase, making it essential for the structural integrity of skin, tendons, blood vessels, and bones. The National Institutes of Health identifies copper as essential for iron absorption and utilization, nervous system development, immune function, and the formation of connective tissue and myelin sheaths around nerve fibers.

The recommended dietary allowance for copper is 900 mcg (0.9 mg) per day for adults, rising to 1,000 mcg during pregnancy and 1,300 mcg while breastfeeding. Copper deficiency, while uncommon in healthy adults, causes anemia that resembles iron deficiency, bone abnormalities, impaired immune function, and neurological problems. Harvard T.H. Chan School of Public Health notes that shellfish, organ meats, nuts, seeds, and legumes are the richest dietary copper sources, and that the interaction between copper and zinc is one of the most important dietary mineral relationships: excessive zinc supplementation suppresses copper absorption by competing for the same intestinal transport proteins.

The 20 foods below are the richest whole-food copper sources available.

20 Foods With the Highest Copper Content

1. Beef Liver: The Most Copper-Dense Food Available

A 3-ounce serving of cooked beef liver provides approximately 14 mg of copper, more than fifteen times the daily requirement in a single serving. The liver is the primary storage organ for copper in the body, concentrating it to extraordinary levels that reflect the organ’s role in copper metabolism and distribution throughout the body. Beef liver also provides exceptional amounts of vitamin B12, iron, folate, vitamin A, and zinc alongside its extraordinary copper content.

The NIH Office of Dietary Supplements lists beef liver at the top of the copper food source list by a wide margin, noting that organ meats provide copper at concentrations that no other food category approaches. The tolerable upper intake level for copper is 10 mg per day, which a full serving of beef liver exceeds, making moderation essential.

Best eaten: Sauteed quickly with onions and balsamic vinegar; limit strictly to once weekly due to very high vitamin A and copper content.

Per 3 oz cooked. Limit strictly to once weekly.

2. Oysters: The Most Copper-Dense Shellfish

A 3-ounce serving of cooked oysters provides approximately 4.8 mg of copper, more than five times the daily requirement alongside extraordinary zinc, selenium, B12, and iron. Oysters are filter feeders that concentrate trace minerals from seawater at exceptional levels, giving them one of the most mineral-dense nutritional profiles of any food per calorie.

Harvard T.H. Chan School of Public Health identifies shellfish, particularly oysters, as the most copper-dense practical everyday food outside of organ meats, noting that their copper and zinc together support the antioxidant enzyme superoxide dismutase that requires both minerals as cofactors.

Best eaten: Steamed or broiled; raw oysters carry foodborne illness risk for immunocompromised individuals and pregnant women.

Per 3 oz cooked.

3. Spirulina: A Concentrated Copper Supplement Food

One tablespoon of dried spirulina provides approximately 0.4 mg of copper alongside protein, iron, B vitamins, and antioxidant phycocyanin. While spirulina is consumed in small amounts as a supplement rather than a primary food, its copper concentration per gram is among the highest of any plant-based source. Regular daily use as a smoothie addition provides a consistent copper contribution.

Best eaten: Blended into smoothies, stirred into water or juice, or added to energy balls; start with small amounts as the strong flavor can be overwhelming in large quantities.

Per 1 tbsp (7 g) dried.

4. Shiitake Mushrooms (Cooked): An Outstanding Plant Copper Source

One cup of cooked shiitake mushrooms provides approximately 1.3 mg of copper, nearly the full daily requirement in a single vegetable serving. Shiitake mushrooms are the most copper-dense commonly available mushroom variety and one of the best plant-based copper sources overall, delivering their mineral content alongside lentinan, a beta-glucan polysaccharide with immune-modulating properties.

The NIH Office of Dietary Supplements identifies shiitake mushrooms among the top plant food copper sources, making them particularly valuable for vegetarians and vegans who cannot rely on organ meats and shellfish for their copper intake.

Best eaten: Sauteed with garlic and olive oil, added to stir-fries and soups, or roasted as a meaty addition to grain bowls; dried shiitake reconstituted in water provides comparable copper to fresh cooked.

Per 1 cup cooked.

5. Cashews: The Most Copper-Dense Common Nut

One ounce of raw cashews provides approximately 0.6 mg of copper, two-thirds of the daily requirement in a single small handful. Among common tree nuts, cashews are the most copper-rich per ounce, making them one of the most practical everyday copper sources for people who eat nuts as a regular snack.

Cashews’ copper works alongside their zinc content in activating superoxide dismutase, the antioxidant enzyme that neutralizes superoxide radicals in cells. Their copper also supports ceruloplasmin production in the liver, enabling efficient iron transport through the bloodstream.

Best eaten: As a daily snack, in cashew butter on whole-grain toast, or blended into dairy-free sauces; choose unsalted raw or lightly roasted varieties.

Per 1 oz (28 g) raw.

6. Sunflower Seeds: A Vitamin E and Copper-Rich Seed

One ounce of dry-roasted sunflower seeds provides approximately 0.5 mg of copper alongside vitamin E, magnesium, and selenium. Sunflower seeds are one of the more copper-dense common seeds and deliver their copper alongside the vitamin E that works in complementary antioxidant pathways to the copper-dependent superoxide dismutase.

Best eaten: As a snack, sprinkled on salads and grain bowls, stirred into oatmeal, or blended into sunflower seed butter; choose unsalted dry-roasted varieties.

Per 1 oz dry-roasted, unsalted.

7. Lentils: A Practical Plant Copper Source

One cup of cooked lentils provides approximately 0.5 mg of copper alongside 18 grams of protein, folate, iron, and magnesium. Lentils are one of the better plant-based copper sources among legumes and are the most practical because they cook quickly without soaking and integrate naturally into soups, stews, and curries.

Best eaten: In soups, dals, and curries alongside tomatoes; red lentils dissolve into creamy soups while green and brown lentils hold their shape for salads and grain bowls.

Per 1 cup cooked.

8. Almonds: A Heart-Healthy Nut With Solid Copper Content

One ounce of almonds provides approximately 0.3 mg of copper alongside magnesium, vitamin E, and calcium. While almonds contain less copper per ounce than cashews, their widespread daily consumption as the most popular tree nut in the United States makes them a consistent background copper contributor for many households.

Best eaten: As a daily snack, sliced over oatmeal and yogurt, or as almond butter on whole-grain toast; choose unsalted roasted or raw varieties.

Per 1 oz (28 g).

9. Dark Chocolate (70-85% Cacao): A Copper-Rich Indulgence

One ounce of dark chocolate with 70 to 85 percent cacao provides approximately 0.5 mg of copper alongside flavanols, iron, and magnesium. Dark chocolate is one of the more copper-dense foods in the standard pantry and one of the few genuinely pleasurable copper sources, making it a nutritionally justifiable daily treat beyond its antioxidant flavanol benefits.

The Mayo Clinic identifies dark chocolate as a meaningful dietary copper source, noting that the higher the cacao percentage, the more copper per serving as dilution from sugar and milk solids is minimized.

Best eaten: One to two squares daily; choose bars with at least 70 percent cacao content and cacao or cocoa listed first.

Per 1 oz, 70-85% cacao.

10. Sesame Seeds (and Tahini): A Copper-Dense Seed

One ounce of sesame seeds provides approximately 1.2 mg of copper, more than the full daily requirement in a single ounce. Tahini, the paste made from ground sesame seeds, provides approximately 0.6 mg of copper per two-tablespoon serving, making it one of the most practical concentrated copper sources in everyday cooking as a dressing base, dip, and sauce ingredient.

Best eaten: Sesame seeds sprinkled on stir-fries and grain bowls; tahini stirred into salad dressings, hummus, and sauces; toasted sesame seeds briefly before use enhances their flavor while preserving most copper content.

Per 1 oz whole sesame seeds.

11. Walnuts: A Polyphenol-Rich Nut With Meaningful Copper

One ounce of walnuts provides approximately 0.5 mg of copper alongside ALA omega-3 fatty acids and polyphenols. Walnuts combine copper with their well-documented brain health and cardiovascular benefits, making their daily consumption nutritionally productive across multiple micronutrient categories simultaneously.

Best eaten: As a daily snack, chopped over oatmeal and salads, or incorporated into trail mix; store in the refrigerator to preserve their delicate polyunsaturated fats.

Per 1 oz (28 g).

12. Chickpeas: A Versatile Legume With Copper

One cup of cooked chickpeas provides approximately 0.6 mg of copper alongside 15 grams of protein, iron, folate, and magnesium. Chickpeas are one of the more copper-dense common legumes and are widely consumed in hummus, curries, and grain bowls, making them a practical everyday copper contributor.

Best eaten: In curries, grain bowls, and salads; roasted with spices as a crunchy snack; blended into hummus with tahini, which compounds the copper content from both chickpeas and sesame in the same dish.

Per 1 cup cooked.

13. Avocado: A Copper-Containing Healthy Fat Fruit

One medium avocado provides approximately 0.4 mg of copper alongside monounsaturated fats, folate, potassium, and vitamins C and K. Avocado’s copper content is often overlooked because it is primarily discussed for its healthy fat and potassium content, but its copper contribution is meaningful and comes packaged with the fat that improves absorption of fat-soluble nutrients from other foods eaten in the same meal.

Best eaten: Sliced on whole-grain toast, mashed into guacamole, added to salads and grain bowls, or blended into smoothies.

Per 1 medium avocado (150 g).

14. Squid (Cooked): A Seafood With High Copper Content

A 3-ounce serving of cooked squid provides approximately 2.1 mg of copper, more than double the daily requirement, alongside selenium, B12, and complete protein. Squid concentrates trace minerals from its marine environment similarly to other shellfish, giving it a mineral density that significantly exceeds most fin fish.

Best eaten: Lightly sauteed in olive oil and garlic, grilled briefly as calamari, or added to seafood stews and pasta dishes; avoid extended high-heat cooking that toughens the texture dramatically.

Per 3 oz cooked.

15. Lobster: A Premium Shellfish With Strong Copper

A 3-ounce serving of cooked lobster provides approximately 1.6 mg of copper, nearly double the daily requirement, alongside selenium, zinc, and B12. Like other shellfish, lobster concentrates trace minerals from seawater at levels that far exceed those in most land-based foods.

Best eaten: Steamed or broiled with a small amount of butter; pairs naturally with lemon and fresh herbs; its high copper content makes even occasional consumption a meaningful mineral contribution.

Per 3 oz cooked.

16. Black Beans: A Kitchen Staple With Meaningful Copper

One cup of cooked black beans provides approximately 0.4 mg of copper alongside 15 grams of protein, iron, folate, and fiber. Black beans are widely consumed in North American and Latin American cooking, making them a consistent background copper contributor for households that eat them regularly.

Best eaten: In rice and bean bowls, tacos, soups, and burritos; canned black beans are convenient; rinse before use to reduce excess starch.

Per 1 cup cooked.

17. Tofu (Firm): A Plant Protein With Copper

A half-cup of firm tofu provides approximately 0.3 mg of copper alongside complete plant protein, calcium, magnesium, and iron. Tofu’s copper content makes it a multi-mineral plant protein that contributes to copper intake alongside its more widely recognized calcium and protein benefits.

Best eaten: Pan-seared, baked, or crumbled into stir-fries and grain bowls; calcium-set varieties provide additional calcium alongside their copper contribution.

Per 1/2 cup firm tofu.

18. Potatoes (With Skin): An Overlooked Copper Vegetable

One medium baked potato with skin provides approximately 0.4 mg of copper alongside potassium, vitamin C, and B6. Potatoes with skin are one of the more copper-dense common vegetables and one of the most widely consumed foods globally, making them an important background copper contributor at the population level despite being infrequently recognized as a mineral food.

Best eaten: Baked whole with skin on to preserve copper and other minerals; the skin contains a disproportionate share of the potato’s copper content so peeling removes most of the mineral value.

Per 1 medium baked with skin (173 g).

19. Pumpkin Seeds: A Mineral-Dense Copper Seed

One ounce of roasted pumpkin seeds provides approximately 0.4 mg of copper alongside magnesium, zinc, iron, and phosphorus. Pumpkin seeds appear throughout this nutrient series as a top-performing seed across multiple minerals, and their copper contribution adds to their already impressive mineral profile.

Best eaten: As a snack, sprinkled on salads and soups, or stirred into oatmeal; choose unsalted roasted varieties.

Per 1 oz roasted, unsalted.

20. Salmon (Wild-Caught): A Fatty Fish With Meaningful Copper

A 3-ounce serving of cooked wild-caught salmon provides approximately 0.3 mg of copper alongside omega-3 fatty acids, vitamin D, B12, and selenium. While salmon is not primarily known as a copper food, its regular consumption two to three times per week contributes a consistent background addition to total copper intake alongside its more celebrated cardiovascular and brain health benefits.

Best eaten: Baked, grilled, or pan-seared; wild-caught varieties provide more consistent mineral content than farmed salmon.

Per 3 oz cooked wild-caught sockeye.

Summary: Top 20 Copper Foods at a Glance

Tips for Getting the Most Copper From Food

Eat a variety of nuts and seeds daily. Cashews, sesame seeds, sunflower seeds, walnuts, and pumpkin seeds are the most practical everyday copper sources for most people. A mixed daily handful covering two to three nut and seed varieties provides a meaningful copper foundation without relying on organ meats or shellfish.

Do not over-supplement zinc. High-dose zinc supplements, particularly those above 40 mg per day taken long-term, competitively inhibit copper absorption and can cause copper deficiency even with adequate dietary copper intake. If you supplement zinc, keep doses within recommended ranges and space zinc supplements away from copper-rich meals.

Include shiitake mushrooms regularly for plant-based copper. Among vegetables, shiitake mushrooms are the most copper-dense by a wide margin. Including them two to three times per week in stir-fries, soups, and grain dishes provides the best plant-based copper strategy for vegetarians and vegans.

Liver once a week covers copper requirements for the entire week. A single 3-ounce serving of beef or chicken liver provides 10 to 15 times the daily copper requirement. For people who eat organ meats occasionally, one weekly liver meal provides far more copper than needed, reducing the importance of other copper sources during that week.

Copper and iron work together. Ceruloplasmin, the copper-dependent protein, is required to mobilize stored iron from the liver and transfer it to transferrin for red blood cell production. People with anemia that does not respond to iron supplementation should have copper status evaluated, as undiagnosed copper deficiency can cause iron-unresponsive anemia through ceruloplasmin insufficiency.

The Bottom Line

Copper is a trace mineral most people meet adequately through a varied diet that includes nuts, seeds, legumes, and occasional shellfish or organ meats, yet its roles in energy production, iron metabolism, antioxidant defense, and collagen synthesis make it foundational to cellular health. Oysters, beef liver, and shiitake mushrooms are the standout sources, while cashews, sesame seeds, dark chocolate, and lentils provide the most practical everyday contributions. The most important copper habit to be aware of is the zinc interaction: excessive zinc supplementation is the most common dietary cause of copper deficiency in otherwise healthy adults, and balancing these two minerals is more important than maximizing copper intake from any single food.

Nutrition data sourced from the USDA FoodData Central database. Individual values may vary based on food preparation, origin, and growing conditions. This article is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare provider before taking copper supplements, as excess copper is toxic and the gap between adequate and harmful intake is relatively narrow.