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| Good Health with Copper |
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  Why
is copper important for good health?
Good health requires a diet adequate in protein, carbohydrates, fats,
vitamins, and minerals. Essential trace minerals, including copper,
are needed only in very small amounts (which is why they are called
'micronutrients').
Copper is necessary for the growth, development, and maintenance of
bone, connective tissue, brain, heart, and many other body organs.
It is involved in the formation of red blood cells, the absorption
and utilization of iron, and the synthesis and release of life-sustaining
proteins and enzymes. These enzymes in turn produce cellular energy
and regulate nerve transmission, blood clotting, and oxygen transport.
Copper stimulates the immune system to fight infections, repair injured
tissues, and promote healing. Copper also helps to neutralize "free-radicals"
which can cause severe damage to cells.
What are good dietary sources of copper?
Copper and other essential trace minerals cannot be formed by the
human body. These minerals must be ingested in the diet. The best
dietary sources of copper include seafood (especially shellfish),
organ meats (such as liver), whole grains, nuts, raisins, legumes
(beans and lentils), and chocolate. Other food sources that contain
copper include cereals, potatoes, peas, red meat, mushrooms, some
dark green leafy vegetables (such as kale), and some fruits (such
as coconuts, papaya, and apples). Tea, rice, and chicken are relatively
low in copper but provide a reasonable amount of copper to the body
because they are consumed in significant amounts.
Although the primary food sources for dietary copper vary regionally,
geographically, and culturally, a balanced diet appears to provide
an adequate intake of copper for most people.
In both developed and developing countries, adults, young children,
and adolescents who consume diets of grain, millet, tuber, or rice
along with legumes (beans) or small amounts of fish or meat, some
fruits and vegetables, and some vegetable oil are likely to obtain
adequate copper if their total food consumption is adequate in calories.
In developed countries where consumption of red meat is high, copper
intake is also likely to be adequate.
Does the body absorb copper easily from all foods?
No. The amount of copper available for absorption depends on the chemical
form of copper in the food, the composition of the total diet, and
the health and nutritional well-being of the individual.
Individuals with chronic digestive problems may be unable to absorb
sufficient amounts of copper, even though the foods they eat are copper-rich.
Some forms of copper are not soluble in stomach acids and cannot be
absorbed from the stomach or small intestine. Also, some foods may
contain indigestible fiber which binds with copper and prevents it
from being absorbed. High intakes of Vitamin C, zinc, and iron can
also decrease copper absorption.
Can you have too little or too much copper?
Yes. If not enough copper is ingested, copper stores in the liver
will be emptied and deficiency leading to disease or tissue injury
(and in extreme cases, death) can result. If too much copper is ingested,
the excess can become toxic, which can also lead to tissue injury
and disease. Between these two extremes, however, the human body is
remarkably capable of balancing a wide range of copper intakes for
the needs of healthy individuals.
While both a deficiency and an excess of copper is very rare, the
World Health Organization is more concerned with copper deficiency.
Recently, concerns have been raised about marginal copper deficiency
(i.e., deficiency that is not severe enough to cause medically-detectable
diseases or tissue injuries but may impair good health in subtle ways,
such as lowered resistance to infection, reproductive problems, general
fatigue or weakness, impaired brain function). More scientific research
is needed to evaluate the nature and extent of these concerns.
How much copper do adults need?
Various national and international organizations concerned with nutrition
and health have standards for copper intake at levels judged to be
adequate for maintaining good health. These standards, or dietary
reference values, are periodically changed and updated as new scientific
data become available. The standards sometimes differ among regions
and organizations. For example, the recommended intake of copper for
healthy adult men and women in North America is 0.9 mg/day. The World
Health Organization recommends a minimal acceptable intake of approximately
1.3 mg/day. These values are considered to be adequate and safe for
most of the general population. Health benefits above the recommended
adequate intake of 0.9 - 1.3 mg/day have not been established.
In North America, a maximum tolerable intake has been established
at 10 mg/day. This is the highest level of copper intake that is not
likely to pose a health risk to most adults in the general population.
It does not mean that 10 mg/day is recommended as a daily intake level.
How much copper do children and adolescents need?
No scientific information is available regarding dietary copper requirements
for children or adolescents. In North America, safe and acceptable
daily intakes have been estimated from adult data. The World Health
Organization, however, has not developed minimum daily intakes for
these age groups.
North American guidelines might underestimate copper needs for these
age groups, but are not likely to overestimate them. Adequate copper
intakes are estimated at 0.3 mg/day for children of 1-3 years; 0.4
mg/day for 4-8 years; 0.7 mg/day for 9-13 years; and 0.9 mg/day for
14-18 years. North American tolerable intakes for these age groups
(i.e., intakes not likely to pose a health risk for most children
in the general population, but for which no additional health benefits
are known) are: 1 mg/day for children of 1-3 years; 3 mg/day for 4-8
years; 5 mg/day for 9-13 years; and 8 mg/day for 14-18 years.
Do pregnant women and mothers who breastfeed need more copper?
Yes. Copper sufficiency in the fetus and in infants is essential for
normal growth and development. Nature has devised a way for the fetus
to get copper from the mother via the placenta and for infants to
get copper via breast milk.
For these reasons, pregnancy and nursing increase the body's need
for copper. The recommended oral intake in pregnant and nursing women
is slightly higher than for non-pregnant, non-nursing healthy women
(approximately 1 mg/day for pregnant women and 1.3 mg/day for nursing
mothers aged 14-50 years).
Can infants become deficient in copper?
Yes. Full-term and premature infants are more sensitive to copper
deficiency than adults. A copper deficiency can create numerous health
problems, including impaired brain development. Since the fetus accumulates
copper during the last 3 months of pregnancy, infants that are born
prematurely have not had sufficient time to store adequate reserves
of copper in their livers and therefore require more copper at birth
than full-term infants.
For full-term infants, the North American recommended safe and adequate
intake is approximately 0.2 mg/day; for premature babies, it is considerably
higher-1 mg/day. The World Health Organization has recommended similar
minimum adequate intakes and advises that premature infants be given
formula supplemented with extra copper to prevent the development
of copper deficiency.
The best source of copper and other essential micronutrients during
the first year of life is human milk. If a full-term infant is not
nursed, fortified baby formula is highly recommended. Cow's milk,
however, contains very low amounts of bioavailable copper and should
be supplemented with copper during the first year of life.
Are copper supplements necessary?
Copper supplements are generally not recommended for healthy adults
who consume a well-balanced diet and eat a wide range of foods. However,
copper supplementation is necessary for premature or low birth weight
infants, infants being fed unfortified formula or cow's milk during
the first year of life, and malnourished young children. Copper supplementation
should also be considered for individuals who have illnesses that
reduce digestion (a danger for children with frequent episodes of
diarrhea or infections and for alcoholics), are unable to eat sufficient
quantities of food (a problem for many elderly people, persons with
eating disorders, on diets, or who are chronically ill), take medications
which block the body's use of copper, are being treated for anemia
with iron supplementation, are recovering from other serious illness
or injury, or are at risk for osteoporosis. Supplementation should
always be administered under a doctor's supervision and caution should
be exercised not to exceed the recommended doses.
If supplements are to be taken, the doctor and consumer should become
aware that different forms of copper have different absorption rates
in the body. For example, cupric oxide is the most common and least
expensive form of copper, but also has the least absorption rate.
Copper gluconate, sulfate, and carbonate have much higher absorption
rates than cupric oxide.
Are any diseases associated with too much or too little copper?
There are several very rare genetic-based diseases that are associated
with the body's inability to distribute (Wilson's Disease) or absorb
(Menkes Disease) copper. These diseases are inherited and cannot be
acquired by non-susceptible persons. Interestingly, the study of these
diseases and the proteins produced by the Wilson's and Menkes genes
have enabled scientists around the world to understand how our bodies
use copper and why it is important as an essential micronutrient.
This knowledge is also leading scientists towards possible cures for
these diseases. Idopathic Copper Toxicosis (ICT), the third genetic
copper metabolic disease, was recognized in the early twentieth century
primarily in the Tyrolean region of Austria and in the Pune region
of India. ICT appears to be vanishing as a result of greater genetic
diversity within these populations and educational programs to ensure
that tinned cooking utensils are used. Only occasional spontaneous
cases of ICT arise today. |
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