The
Benefits of Zinc
The Benefits of Zinc
By: Dr. George Obikoya
Zinc is an essential mineral that is found in every
cell in our body. It stimulates the activity of about 100 enzymes,
substances that promote biochemical reactions in your body. Among
its many functions, zinc helps maintain a healthy immune system,
is needed for wound healing, helps maintain your sense of taste
and smell, and is needed for DNA synthesis. Zinc also supports normal
growth and development during pregnancy, childhood, and adolescence,
and helps sperm develop and is needed for ovulation and fertilization.
Taking lozenges made of zinc gluconate can help shorten the length
of a cold. Most forms of zinc work equally well, but if you're trying
to prevent a cold, use zinc lozenges or a zinc spray made of zinc
gluconate. Take 15 mg of zinc daily (the amount in most multivitamins).
Because zinc can block copper absorption, make sure that your supplement
also contains 1 to 2 mg of copper.
To fight colds, use a zinc nasal spray four times a day or suck
on zinc lozenges that contain 15 to 25 mg of zinc gluconate every
two to four hours as soon as you notice symptoms. Stop when symptoms
subside. Consuming zinc on an empty stomach can cause nausea, so
take zinc supplements with food.
Zinc deficiency most often happens when its intake is inadequate
or it is poorly absorbed, when there are increased losses of zinc
from the body, or when the body’s requirement for zinc increases.
Zinc deficiency manifests as growth retardation, hair loss, diarrhea,
delayed sexual maturation and impotence, eye and skin lesions, and
loss of appetite. Necessary amounts of zinc can be found in a high-quality
liquid multivitamin.
Weight loss, delayed healing of wounds, taste abnormalities, and
mental lethargy can also occur with zinc deficiency. Since many
of these symptoms are general and are associated with other medical
conditions, do not assume they are due to a zinc deficiency without
consulting your doctor.
Risk factors for zinc deficiency include: inadequate caloric intake,
alcoholism, and digestive diseases. Vegetarians may need as much
as 50% more zinc than non-vegetarians because of the lower absorption
of zinc from plant foods, so they need to have good sources of zinc
in their diet.
Maternal zinc deficiency can slow fetal growth. Growth rate improves
in children with mild to moderate growth failure and who also have
a zinc deficiency when given zinc. Human milk does not have enough
zinc for older infants between the ages of 7 months and 12 months,
so breast-fed infants of this age should also consume age-appropriate
foods containing zinc or be given formula containing zinc or zinc
supplementation.
Breastfeeding also may deplete maternal zinc stores because of the
greater need for zinc during lactation. Include good sources of
zinc in your daily diet if you are breast-feeding.
30% to 50% of alcoholics are zinc deficient. Alcohol decreases the
absorption of zinc and increases loss of zinc in urine. Further,
many alcoholics do not eat an acceptable variety or amount of food,
so their dietary intake of zinc may be inadequate.
Diarrhea causes zinc loss. Those who have had gastrointestinal surgery
or who have digestive disorders that result in malabsorption, such
as sprue, Crohn’s disease and short bowel syndrome, may lack zinc.
Take additional zinc if you have any of these problems.
Zinc deficiency compromises your immune system. Zinc is required
for the development and activation of T-lymphocytes, a kind of white
blood cell that helps fight infection. When zinc supplements are
given to individuals with low zinc levels, the numbers of T-cell
lymphocytes circulating in the blood increase and the ability of
lymphocytes to fight infection improves dramatically.
The effect of zinc treatments on the severity or duration of cold
symptoms is controversial, because changing even the type of zinc
can alter the outcome of a study. A study of over 100 employees
of the Cleveland Clinic indicated that zinc lozenges decreased the
duration of colds by one-half, although no differences were seen
in how long fevers lasted or the level of muscle aches. Other studies
examined the effect of zinc supplements on cold duration and severity
in over 400 randomized subjects. In their first study, a virus was
used to induce cold symptoms. The duration of illness was much shorter
in the group receiving zinc gluconate lozenges (providing 13.3 mg
zinc) but not in the group receiving zinc acetate lozenges (providing
5 or 11.5 mg zinc). Therefore it is advised to stick to zinc in
the gluconate form.
Some researchers have questioned the effect of iron fortification,
to prevent iron-deficiency anemia, on absorption of other nutrients,
including zinc. Fortification of foods with iron does not significantly
affect zinc absorption. However, large amounts of iron in supplements
(greater than 25 mg) may decrease zinc absorption, as can iron in
solutions. Taking iron supplements between meals will help decrease
its effect on zinc absorption, but caution must be used as the body
has a maximum level of daily iron intake before it becomes toxic.
Zinc toxicity has been seen in both acute and chronic forms. Intakes
of 150 to 450 mg of zinc per day have been associated with low copper
status, altered iron function, reduced immune function, and reduced
levels of high-density lipoproteins (the good cholesterol), so be
sure to keep your zinc intake below these levels.
A good multivitamin is the foundation of health
and nutrition. Take a look at our scientific reviews of many of
the popular brands for factors such as ingredients, areas of improvement,
quality level, and overall value. If you are looking for a high
quality liquid multivitamin, we suggest that you take a look at
the Multivitamin
Product Comparisons.
VITAPLEN COMPLETE™ contains a patented AquaMin(TM) Trace Minerals Complex and 165 scientifically formulated nutrients--all in a highly absorbable liquid formula.
References
1. Sandstead HH. Understanding zinc: Recent observations and interpretations.
J Lab Clin Med 1994;124:322-327.
2. Institute of Medicine. Food and Nutrition Board. Dietary Reference
Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper,
Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium,
and Zinc. National Academy Press. Washington, DC, 2001.
3. Solomons NW. Mild human zinc deficiency produces an imbalance
between cell-mediated and humoral immunity. Nutr Rev 1998;56:27-28.
4. Prasad AS. Zinc: An overview. Nutrition 1995;11:93-99.
5. Heyneman CA. Zinc deficiency and taste disorders. Ann Pharmacother
1996;30:186-187.
|
