Zinc in the Diet
Zinc is a trace mineral needed for a healthy body. It has many
functions. Also, it is a part of several enzymes.
Information
The Recommended Daily Allowance, called RDA, for
zinc is 15 mg for males, age 11 and over and 12 mg for females, age
11 and over. Pregnant women
should get 15 mg.
Women who are breastfeeding
should get 19 mg the first six months and 16 mg the second six months.
A well-balanced diet will provide about 10 to 15 mg per day. Stomach acid
is important to the absorption of zinc. Health problems or medicines that
lower stomach acid could limit the amount of zinc that the body absorbs.
Zinc deficiency could lead to:
slowed growth
reduced taste, smell, and vision
poor appetite
mental lethargy
low sperm count
birth defects
impaired nerve conduction
nerve damage
poor healing of wounds
skin changes
reduced resistance to infections
Several factors can lead to a zinc deficiency. One is a
high-fiber
diet that contains a lot of phytates. These are found in unrefined
cereal and unleavened whole grain products. Phytates bind to zinc and
reduce its absorption. The leavening agents used in most breads usually
deactivate the phytates.
Another factor is not getting enough zinc in the diet.
Vegetarians,
especially vegans who do not eat meat, eggs, dairy products,
and seafood, may have a harder time taking in enough zinc. Taking
large amounts of iron or copper in the form of supplements or from fortified
foods without taking zinc, can also result in a zinc deficiency. Groups
at higher risk for this are pregnant women, the elderly,
and athletes.
Some studies suggest that zinc may help cure the
common cold or at least decrease the length of a cold. Zinc lozenges
are a big seller for this reason. More research needs to be done to
prove this theory. Zinc is not too toxic in doses up to 45 mg per day.
Doses higher than 150 mg can cause diarrhea, abdominal cramps, and
vomiting. High doses can also interfere with the body's immune function.
Taking doses higher than the recommended level can also prevent
copper, another key mineral, from being absorbed well by the body. This can cause a
copper deficiency. High doses can also reduce iron absorption.
Megadoses of zinc may also lower HDL,
known as the good, cholesterol levels. Taking more than the recommended
amount of zinc from a supplement has no proven benefits. As noted, it can cause
several risks.
Eating lean meat on a regular basis will ensure the proper level of zinc
intake. Vegetarians can meet the RDA for zinc by eating a variety of beans,
cheese, milk, nuts, seeds, wheat germ, and soy products.
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