Abstract: Copper is an essential mineral used in the body for the proper functioning of the immune system, the transport and utilization of iron, the development of the brain, glucose and cholesterol metabolism, creation of red and white blood cells, and bone health. Copper is associated with cardiovascular health, and copper levels are being investigated in connection to Alzheimer's disease. During pregnancy, the need for copper increases, however, the need is still small, and most individuals will obtain adequate copper from food. Seeds, grains, nuts, beans, and shellfish are excellent copper sources. Since it is fairly easy to get copper from food, copper supplementation is not generally recommended during pregnancy. Still, it should be utilized alongside zinc supplementation to ensure adequate intake. 

What is Copper? Why Do I Need It? 

Copper is an essential microelement found in all living organisms. It is involved in the function of several enzymes used in protein catalytic reactions that carry out biological functions critical to growth and development. Copper-containing enzymes play vital roles in many oxidative processes and in the production of most of the energy required for metabolism. These copper-reliant enzymes are essential in the body's defense against free radicals, in the synthesis of connective tissue, in the transport and utilization of iron, in the creation of norepinephrine, and in the regulation of brain development and functioning. Copper also plays a role in bone strength, impacting the onset of osteoporosis and other bone defects. It contributes to the maturation of red and white blood cells. And is involved in the metabolism of cholesterol and glucose. 

These copper-containing enzymes are called cuproenzymes. The most abundant one being ceruloplasmin, which plays a role in iron metabolism and carries more than 95% of total copper in healthy human plasma. 

Cardiovascular Risk Factors 

Copper deficiency leads to changes in blood lipid levels, a risk factor for atherosclerotic cardiovascular disease.  Since low copper levels decrease cardiac cuproenzymes' activity, an association exists between cardiac abnormalities and low copper levels. One study found that the highest tertile of copper intake (2.29 mg/day) corresponded with diastolic blood pressure, total cholesterol, and LDL cholesterol levels significantly lower than the lowest tertile of copper intake. However, a few small studies could not demonstrate that copper supplementation in healthy adults influences CVD risk factors. Daily supplementation with 2 mg of copper glycinate for eight weeks increased the activity of two cuproenzymes but did not affect five CVD-related plasma markers.

Alzheimer's Disease

Research in this area is still determining whether high or low serum or plasma copper levels are associated with Alzheimer's disease risk and whether supplements containing copper could affect disease risk. There have been several reports of low copper levels and low activity of copper-dependent enzymes in the brains of people with the disease. Thus, some experts believe that dietary copper deficiency plays a role in the etiology of Alzheimer's disease. In a complete reversal, excessive intake of copper and iron could also contribute to cognitive issues in some individuals, as high copper levels have been found in the brains of people with Alzheimer's disease. Some researchers argue that excess amounts of dietary copper are involved in the development of the disease. Recent findings reported that alteration of the homeostasis of biological metallic ions, including zinc, iron, aluminum, and copper plays a vital role in the pathogenesis of Alzheimer's disease. These findings show that plasma and free serum copper levels are known to elevate with aging in AD brains. Elevated free copper in the blood negatively correlates with cognition and predicts the rate of loss of cognition. Overall, further research should be done. 

Copper and Iron - What is the Relationship? 

Intestinal iron absorption, iron release from stores, and iron incorporation into hemoglobin are copper-dependent processes that require adequate copper intake. Copper assists in preventing anemia, which can be caused by defective iron mobilization resulting from reduced copper-dependent enzyme activity. This particular enzyme, ceruloplasmin, is fundamental to transforming Fe2+ (ferrous iron) into Fe3+ (ferric iron). This step is necessary for the incorporation of iron into circulating transferrin. Otherwise, iron remains trapped in a part of the immune system and is not available for erythropoiesis, red blood cell formation. 

Current research is beginning to understand the importance of copper and iron working together to promote normal fetal growth and development. 

Iron deficiency during pregnancy is common, and the negative impact of iron deficiency anemia is well documented. It also affects the metabolism of other metals and mediators of cell function, influencing the impact of a copper deficiency. Although less common, copper deficiency has deleterious effects and is particularly harmful during pregnancy, when the developing fetus is vulnerable to inappropriate micronutrient status. 

Why Is Copper Important During Pregnancy? 

Inappropriate nutrition is being targeted more and more as a significant contributor to a wide array of fertility and pregnancy issues. And copper is no exception. Copper deficiency can cause infertility, congenital abnormalities, stillbirths, and low birth weight. Copper also works hand in hand with iron, ensuring both micronutrients effectively operate in the body as the baby develops.

During pregnancy, the need for copper increases. Maternal serum copper and ceruloplasmin (copper enzyme) concentrations increase throughout pregnancy and suboptimal supply may have adverse effects on developing tissues and organ systems, including the lung, skin, bones, and immune system. However, the extent to which copper deficiency influences human prenatal development is still being researched and debated. 

Copper helps maintain healthy iron levels during pregnancy and beyond. Other minerals like copper must also be in good supply to avoid iron-deficient anemia during pregnancy. We do not need a lot of copper, but the need for it does increase during pregnancy. 

Am I Getting Copper From Food? 

Copper is an excellent mineral to get from food. Oysters and chocolate are the richest sources of copper in the diet. Yum! Yet, the most common dietary sources of the mineral are seeds, grains, nuts, beans, shellfish, wheat bran cereals, and whole-grain products. 

The copper content in drinking water can also be a viable source of copper. Soft, acidic water has a high copper concentration, especially if it is conducted through a copper pipeline. Estimating the range of copper in drinking water, an adult who ingests two liters of water daily will obtain approximately 13-50% of the adequate daily dietary intake of copper. 

The absorption of copper is typically high compared to that of other trace minerals. The amount of copper in the diet strongly influences bioavailability, ranging from 75% of dietary copper when the diet contains only 0.4 mg/day to 12% when the diet contains 7.5 mg/day. Specific prebiotics, naturally present or added to food, such as pectin and inulin, positively affect copper absorption. 

A breakdown of the copper content in various foods is shown below: 

• Oysters (3 ounces) 4,850 mcg
• Baking Chocolate, unsweetened (1 ounce) 938 mcg
• Potatoes (1 medium) 675 mcg
• Mushrooms ½ cup 650 mcg
• Cashew nuts (1 ounce) 629 mcg
• Crab, Dungeness (3 ounces) 624 mcg

Although not high in copper, U.S. adults consume bread, potatoes, and tomatoes in sufficiently large amounts, substantially contributing to copper intake. Copper and magnesium are highly correlated in US diets, and food groups high in folate tend to be high in copper.

Who Is At Risk For a Deficiency? 

Overt copper deficiency in humans is rare, without an associated disease; however, some at-risk individuals will struggle with copper intake during pregnancy. Also, signs of moderate copper deficiency are thought to be more common. Inadequate dietary intake of the element may be the rarest cause for deficiency; however, conditional copper deficiencies can arise from genetic factors, nutritional interactions, drugs or other chemicals, and disease states. Consumption of high concentrations of zinc in the diet and relatively low amounts of zinc supplementation can induce a secondary copper deficiency since these two elements have very similar chemical properties. The Institute of Medicine has recommended that copper supplements be provided alongside zinc supplements during pregnancy. 

As a result of intestinal malabsorption due to intestinal lining alterations, those with Celiac disease are at an increased risk of copper deficiency. In a study of 200 adults and children with celiac disease, 15% had a copper deficiency. 

Dietary factors, including iron, vitamin C, and zinc, exert adverse effects on the bioavailability of copper. Lead poisoning, hemochromatosis, and excessive ingestion of soft drinks produce more subtle results. 

What About Toxicity? 

Chronic exposure to high levels of copper can lead to liver damage and gastrointestinal symptoms (abdominal pain, cramps, nausea, diarrhea, and vomiting). Due to precise internal homeostatic control of copper, copper toxicity is rare in humans. 

Free copper in cells and the body is extremely low; copper almost always exists in biological systems bound to proteins. However, there may be instances where the ingestion of high copper levels overrides innate checkpoints designed to regulate overall body copper levels. 

A couple of Tolerable Upper Limits have been defined to prevent copper toxicity. 

1. An upper tolerable intake level of 10 mg (10,000 mcg)/day has been established. 
2. A recommended upper limit for copper in public water systems is set at 1.3 mg/L.

Water containing high levels of copper due to stagnant water in copper-containing pipes and fixtures and copper alloys in water distribution systems can result in copper toxicity. 

Do I Need A Copper Supplement? Which Form Is Best? 

Dietary sources of copper are superior to supplemental sources of copper. Particularly if you are not taking a zinc supplement or do not have another deficiency risk factor, you should be able to get plenty of copper from food. An official recommendation of the Institute of Medicine back in 1990 declared that prenatal copper supplementation is not recommended. However, if a zinc supplement is administered, the Institute of Medicine recommends taking a 2 mg copper supplement.  

Despite the increased need, supplementation is generally not recommended during pregnancy. However, it may depend on individual circumstances. Copper is available in dietary supplements containing only copper, in supplements containing copper in combination with other ingredients, and in many multivitamin/multimineral products. These supplements have many forms of copper, including cupric oxide, cupric sulfate, copper amino acid chelates, and copper gluconate. To date, no formal studies have been performed comparing the bioavailability of the various copper forms. 

How Much Copper Do I Need? 

The RDA for pregnancy is 1300 mcg (1.3 mg) compared to 900 mcg (0.9 mg) in a nonpregnant state. 

How Do I Know If I Am Getting Enough Copper? 

Copper status is not routinely assessed in clinical practice - and no biomarkers that accurately and reliably determine copper status have been identified. Measurements of serum copper and ceruloplasmin concentrations in relation to "normal ranges" are currently used to evaluate copper status. Ceruloplasmin carries the majority of copper in the blood, so the amount of circulating ceruloplasmin reflects alterations in blood copper to some extent.  

However, plasma CP and copper levels can be influenced by other factors, such as estrogen status, pregnancy, infection, inflammation, and some cancers. These markers are not sensitive to marginal copper deficiencies but decrease in severe to moderate copper deficiency. 

Serum concentrations of copper and ceruloplasmin change in relation to age and sex as well. It is well known that adult women have higher concentrations of serum copper than men. These markers can be slightly higher in the morning compared to other times of the day and will increase in response to inflammation, infection, and anticonvulsant or estrogen therapy. Circulating copper may be unexpectedly high during inflammation and may not reflect the actions of copper-dependent enzymes in cells. 

Prenatal Vitamin Brands: What's the Copper Amount and Type in Popular Prenatal Brands?

Prenatal Analysis:

To properly analyze these prenatals from a copper perspective, it is also important to look at their zinc content. Parsley Health Prenatal, FullWell Prenatal, Seeking Health, Designs For Health, and Perelel contain at least 13 mg of zinc, and thus, it is astute that these prenatals also contain at least 0.75 mg of copper. Modern Fertility and NatureMade contain 11 mg of zinc but do not include copper in their formulations. Ritual prenatal avoids zinc and copper supplementation entirely. Overall, copper supplementation is not necessary if proper amounts are obtained from food; however, if utilizing zinc supplementation, including copper is ideal. Most of the brands seem consistent in using the copper bisglycinate chelate form. 

Resources:

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