An overview of dietary copper
Copper is an essential mineral that the body has to source from the food we eat. The body needs very little amounts of copper to function normally. You need only about 10mg of the mineral in a day. And this is the upper limit. Amounts above this can cause serious health issues. Despite this fact, the mineral plays important life-sustaining functions that the body cannot do without. It is needed for:
- Formation of red blood cells
- Maintenance of a healthy immune system
- Maintains the integrity of the connective tissues including collagen and bones
- Helps in mopping up excess free radicals
- Protects the DNA
- It supports iron metabolism
- It is needed for energy production
Metabolism of copper
This function depends on the amount of copper absorbed from the small gut. It can also be taken up from the stomach where the stomach acid promotes its solubility. This suggests that a healthy digestive system is important for the uptake of copper. One way of doing this is by ensuring that your gut has adequate digestive enzymes and by eliminating parasites in addition to a healthy diet and lifestyle.
Copper can cross the placenta and it is stored in the liver where it is bound to albumin. The rate of absorption is usually determined by the amount of copper available in the food taken. For example about 50% of an intake of 1mg of copper in the gut will be absorbed. However, only about 20% of a 5mg of copper in the gut will be absorbed.
Excretion is through the urine. A healthy kidney will lead to minimal copper loss in the urine but a diseased kidney can lead to high losses of the mineral. On the other hand, if there is high dietary copper, some of it will be excreted into the gut for possible resorption when necessary. This absorption and resorption mechanism helps to avoid deficiency or toxicity situations.
Overt copper deficiency is rare. When it occurs, it is usually due to an underlying disease or genetic condition rather than due to poor dietary intake. On the other hand, poor copper intake affects a sizable part of the U.S population. Up to about a quarter of the population is said to suffer varying degrees of deficiency. This can lead to signs and symptoms that include:
- Chronic fatigue
- Susceptibility to infections
- Bone fractures
- Skin patches (loss of pigments)
- Signs and symptoms of thyroid disorders
- Some types of cancer
- Reproductive health problems
- Bone disorders such as loss of bone density (osteoporosis)
- Rheumatoid arthritis
- Neurological disorders
- Heart symptoms
- Vascular disorders
Risk factors for copper deficiency
- Certain genetic disorders that lead to abnormal copper metabolism
- Premature babies who are fed on formula feeds
- The elderly who are likely to have problems with eating quantity and quality foods
- Patients who have had gastric bypass surgery,
- Patients with malabsorption disorders
- Pancreatic cancer
- Breastfeeding mothers
- A diet made of mainly refined foods
- Over-farmed soils
The relationship between copper, iron, and zinc
A balance between these three minerals is needed for the normal functions of each. High zinc intake antagonizes copper absorption. This is also the case with high levels of iron. Copper is needed for iron metabolism and that’s why anemia may be a pointer to copper deficiency.
When these minerals are part of a multi-mineral supplement, it is important that they be in the right ratios to avoid the undesirable situation where one antagonizes the other.
Sources of dietary copper
Copper can be sourced from animal or plant foods. Plant sources include:
- Cashew nuts
- Sesame seeds
- Whole grains
- Green leafy vegetables such as kales and broccoli
- Black pepper
- Dried fruits
Nutritional supplements are also a good source of copper. They help to fill the gap left by inadequate dietary intake or excessive loss due to disease. If used beyond what is recommended, supplements can easily lead to copper toxicity. However, a good supplement contains only small amounts of copper. For example, Basic, a multivitamin-multi-mineral supplement from Belisan contains only 0.25mg of copper. This is only 13% of the recommended daily intake. At that level, toxicity is almost impossible to occur under normal circumstances.
Health benefits of copper
Adequate level of copper in the body leads to many health benefits. These include:
- Strong bones
- Healthy sexual and reproductive health
- It is a powerful antioxidant that keep free radicals (reactive oxygen species) within normal levels
- Help to protect the integrity of the DNA
- Helps in the normal production of collagen
- Supports healthy skin and hair
- Protects brain cells
- Helps to maintain health hemoglobin levels
This depends on a number of factors. For normal intake, the total daily dosage is determined according to age as follows.
- Infants up to 6 months - 0.2mg
- Babies 6-12 months – 0.22mg
- Children 1-3 years – 0.34mg
- 4-8years – 0.4mg
- 9-13 years – 0.7mg
- 14—18 years – 0.89mg
- Over 19 years 0.9mg
Pregnant and breastfeeding mothers need 1.0mg and 1.3mg respectively.
Dietary copper is unlikely to show any interaction with other food nutrients or medications. When taken as a supplement however, chances of interactions can occur. This can happen with:
- Hormonal contraceptives
- Estrogen preparations
- Aspirin, ibrufen, and other nonsteroidal anti-inflammatory drugs (NSAIDs).
- Gout medications
- Some heart medications
- Some peptic ulcer drugs
If you are on any medications, it is advisable to talk to your doctor before you consider taking copper supplement. For a wholesome composite nutritional supplement containing copper, click here.
Institute of Medicine (US) Panel on Micronutrients. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington (DC): National Academies Press (US); 2001. 7, Copper. Available from: https://www.ncbi.nlm.nih.gov/books/NBK222312/
Megan Ware RDN LD. (2017, October 23). "Health benefits and risks of copper." Medical News Today. Retrieved from https://www.medicalnewstoday.com/articles/288165.php
Pizarro, F., Olivares, M., Uauy, R., Contreras, P., Rebelo, A., & Gidi, V. (1999). Acute gastrointestinal effects of graded levels of copper in drinking water. Environmental Health Perspectives, 107(2), 117–121.