Copper is an essential trace mineral in the body, and is more abundant in humans than all but two other trace minerals (iron and zinc). Its primary role is to help enzymes function properly, which means it’s involved in a range of the body’s processes, namely:
Elimination of free radicals
Development of bone and connective tissue
Production of melanin, a skin and hair pigment
Still, the amount of copper that the body needs is small — less than the amount in a penny — and studies are finding that too much copper can lead to a number of health problems.
Copper and Alzheimer’s Disease
Most recently, a study in the journal Archives of Neurology found that elderly people who had diets high in copper, along with saturated and trans fats, had faster mental decline, which could be associated with Alzheimer’s disease.
In the study, among those who ate at least 1.6 milligrams of copper a day (the recommended daily amount is 0.9 milligrams), along with foods high in saturated and trans fat, many progressed their rate of mental decline the equivalent of 19 years.
Why would copper be related to Alzheimer’s? It’s thought that too much of the mineral may hinder the body’s ability to get rid of proteins that form plaques, which are found in the brains of people with Alzheimer’s disease.
Copper Toxicity: Health Effects
Copper has been found in higher levels in the bloodstream of people with Alzheimer’s disease, but too much copper can cause other health problems as well.
If you take in too much copper, you may have abdominal pain, cramps, nausea, diarrhea, vomiting and liver damage. Meanwhile, elevated copper levels, in particular when zinc levels are also low, have been linked to a number of conditions, including:
Fatigue and headaches
Muscle and joint pain
Autism and childhood hyperactivity
Copper toxicity is of particular concern to pregnant women, as copper levels nearly double in women during this time. It can take three months after delivery for copper levels to return to normal, and the excess copper during this time has been linked to postpartum depression in some women.
How are We Exposed to Copper?
We get copper from our diets in foods like liver, mushrooms, spinach, greens and other vegetables, nuts, shellfish, legumes, some fruits, potatoes and chocolate.
However, it’s not likely that you’ll overdose on copper from dietary sources alone. In fact, most Americans consume less than the recommended amounts of copper in their diets. In the Alzheimer’s study above, many of the participants with high copper levels got them from taking multivitamins that contained copper.
You can also be exposed to copper from drinking water that travels through copper pipes, and even cooking with copper cookware can increase the copper levels in foods.
How Much Copper Should You Get?
Copper is an important mineral, and not getting enough of it can lead to a number of health problems as well (iron-deficiency anemia, osteoporosis, elevated LDL cholesterol and low HDL cholesterol, to name a few). However, copper deficiency is relatively rare in the United States.
The U.S. daily recommended intake of copper is 0.9 milligrams, which should be easily attainable by eating a healthy diet with a variety of fruits, vegetables, nuts and legumes. For instance, 5 ounces of raw crimini mushrooms will give you over 35 percent of your daily value of copper, 1 cup of boiled spinach will give you over 15 percent, and 1/4 cup of raw cashew nuts will give you 38 percent.
If you are concerned about getting too much copper, the primary routes to reduce exposure would be to:
Not take a multi-vitamin that contains extra copper
Find out if your drinking water travels through copper pipes, and consider alternative water sources if it does
Not use copper cookware
Avoid foods extremely high in copper, such as organ meats (four ounces of liver will give you over 450 percent of the recommended daily amount of copper)
Archives of Neurology August 2006;63(8):1085-8
MSNBC August 14, 2006
The World’s Healthiest Foods: Copper