During the last three decades, zinc has
been established as an essential nutrient for humans. Deficiency symptoms range
from subclinical or mild to severe and debilitating.
Zinc sulphate
Vitamin B6
Glutamine
Magnesium
Zinc is definitely one of the most, if not
the most, important trace element. Zinc has profound effects on an individual’s
health. Deficiency of this important mineral can lead to years of unnecessary
suffering.
clinical applications
Mild deficiency - (Category 2, Zinc Taste
Test)
delayed wound healing
low testosterone
low sex drive
low sperm count and fertility
low muscle mass
behavioural changes
neurosensory changes
(e.g., taste, sight, smell, balance)
low immune function and recurrent
infections
Moderate deficiency -
(Category 1-2, Zinc Taste Test)
growth retardation
hypogonadism
rough skin
poor appetite
mental lethargy
delayed wound healing
immune dysfunction
loss of taste
Severe deficiency - (Category 1, Zinc Taste
Test)
anorexia
bulimia
dementia
pustular dermatitis
alopecia
diarrhoea
emotional disorders
weight loss
recurrent infection
neurosensory loss
immune dysfunction
persistent ulcerations
delayed healing
Technical information
Is zinc deficiency a common problem?
Many dietary choices can lead to zinc
deficiency. Numerous research studies have found that suboptimal levels of zinc
are very common at all ages, especially in the
elderly.1 ,2 ,3 ,4 An Australian study found, in a
national random dietary survey, that 85% of women and 65% of men do not receive
the RDA for zinc in their diets.5 Also reported was that 50% of men and
35% of women do not receive the RDA for magnesium. This very strongly suggests
that deficiencies of these nutrients are widespread.
A high alcohol intake or a high sugar
intake causes a dramatic increase in urinary zinc excretion. People consuming
diets that regularly contain high calorie, low nutrient value foods will, over
time, gradually develop a zinc deficiency.
In disorderition, many women taking birth
control pills develop zinc deficiency because of the antagonistic effect of the
birth control pill upon zinc in the body. Some researchers feel that the use of
birth control pills in the treatment of menstrual dysfunction can cause a zinc
deficiency which may lead to anorexia nervosa or bulimia. People taking birth
control pills could pay close attention to their zinc status to avoid the
negative effects of zinc deficiency.
A study conducted in Denver identified that
66% of the children who were below average height and weight were zinc
deficient.6 Doctors treating injuries find that four out of every ten
patients needed zinc. In disorderition, a variety of diseases can produce
deficiencies of zinc. Alcoholism, kidney problems requiring dialysis treatment,
pancreatic dysfunction, and other digestive problems have all been shown to
produce zinc deficiency. Also, patients with AIDS have been found to be zinc
deficient. A significant number of people in Australia suffer from either
chronic or acute zinc deficiency and experience health problems as a result.
After considering this, one might conclude
that it would be a good idea for everyone to take zinc, since zinc supplements
are reasonably inexpensive and easy to obtain. However, that would also be a
mistake. In the last few years researchers have discovered that a high intake
of zinc for prolonged periods can produce a copper deficiency – and copper
deficiency will produce its own set of health problems. It is thus clear that
it would not be a good idea to regularly supplement with large doses of zinc.
Zinc deficiency
Mild zinc deficiency states produce weight
loss, reduced sperm counts, and increased levels of ammonia in the body.
Moderate zinc deficiencies produce growth retardation, skin changes,
hypogonadism in males, mental lethargy, poor appetite, delayed wound healing,
taste abnormalities, abnormal dark adaptation, and impaired or absent ability
to react to specific antigens, a cell-mediated immune disorder. Severe zinc
deficiencies are manifested by a blister-producing form of dermatitis, complete
or partial hair loss, diarrhoea, emotional disorders, weight loss, severe
recurrent infections or immune deficiency, hypogonadism in males, and death.
It has been recognised that nutritional
factors in several disease states contribute to zinc deficiency. Studies also
show that common dietary amounts of zinc in a developed country like the United
States may be sufficiently low to cause health problems.
An easy and practical zinc assessment tool,
the Zinc Taste Test, has been demonstrated to accurately represent the
functional zinc status of a patient by investigating their taste response to a
zinc sulphate solution7 8 (see Zinc Taste Test).
Zinc absorption
Absorbing zinc is not as easy as it sounds.
Some people do not absorb zinc efficiently, even when taking a zinc supplement.
After taking zinc sulphate or zinc chelate tablets, some people still do not
develop taste perception for the Zinc Taste Test. Therefore, supplements
producing better zinc absorption are required. USTIFY"Glutamine is the
most abundant free amino acid in the human body. The nonessential amino acid
glutamine has received much research attention recently due to its significant
effects on immune activity10 11 12 , glycogen regulation13
brain function14 and gastrointestinal mucosal function and
morphology.15 16 The mention of a glutamine deficiency state may
seem contradictory for a nonessential amino acid: however, insufficiencies have
been noted and beneficial effects seen in specific pathologies and it is
probably more accurately termed a conditional amino acid. During acute trauma
or critical illness, circulating glutamine levels are reduced and complications
can be avoided by glutamine supplementation.17 18 19 In some
patients supplementation with glutamine may be essential.20 The small
intestine is dependent on glutamine as a fuel substrate and begins to
degenerate in glutamine deficiency states. Experimental studies revealed that
glutamine deficiency causes a necrotising enterocolitis, increase small bowel
permeability21 and increases the mortality of animals subjected to
bacterial stress.22 Patients undergoing bone marrow transplants who were
supplemented with glutamine showed a lower incidence of infections and shorter
hospital stays. Those patients who are low in zinc are likely to benefit from
disorderitional glutamine and to be able to absorb nutrients, including zinc, more
effectively.
Vitamin B6
Almost every biochemical reaction involving
amino acids requires vitamin B6 as a cofactor. This makes vitamin B6 a
fundamental nutrient in the production of hormones, neurotransmitters enzymes,
proteins and cellular constituents. This is why vitamin B6 is so essential for
the developing foetus, for growth, brain function and hormonal regulation.
Zinc is required for, as well as many other
functions, the reading and copying of all genetic material. This, like vitamin
B6, makes zinc fundamental in the production of all new proteins and tissues,
and wherever we use vitamin B6 we are likely to require zinc zs well.
Supplementation of zinc of a patient with a vitamin B6 deficiency is unlikely
to give consistent good results and cosupplementation is recommended.
Vitamin B6 also assists zinc absorption by
facilitating picolinic acid production. Picolinic acid is a product of
tryptophan metabolism. One of the enzymes in the pathway from tryptophan to
picolinic acid requires vitamin B6 as a cofactor.23 Studies show that
zinc absorption is depressed in laboratory animals fed marginal vitamin B6
levels24 , and in animals fed a B6 antagonist25, probably due to
inhibition of picolinic acid production. Vitamin B6 deficiency results in a
decreased zinc content in the plasma, liver, pancreas, and heart tissues of
laboratory animals. A highly significant increase in radioactively tagged zinc
was also observed in the gastrointestinal tract and faeces of vitamin B6
deficient animals.
High dose vitamin B6 may result in a
peripheral neuropathy similar to that caused by B6 deficiency. It is thought that
those people at risk of developing the symptoms of vitamin B6 deficiency are
magnesium deficiency and cosupplementation is recommended.
DNA and Growth
The reason zinc has such broad effects on
human health is that it is essential for the production and function of RNA and
DNA. A defect in synthesis or function of RNA or DNA causes a variety of health
disorders.
Since RNA and DNA control growth of the
human body, a zinc deficiency will cause growth impairment. Many children whose
height or weight are less than normal may be zinc deficient. Often, proper zinc
supplementation of these children can restore their growth rate to normal and
allow them to develop to full potential.
In disorderition to growth impairment, another
effect of zinc deficiency in children is dental cavities. Dental cavities in
children’s teeth, reduced body size, skin rashes, or allergies should be
considered as possible signs of a zinc deficiency.
Injuries
Along with growth impairment, zinc
deficiency impairs the body’s ability to heal itself. People with injuries
which do not heal properly may be experiencing the adverse effects of a lack of
zinc. Identifying the need for zinc and supplementing zinc can be helpful in
accelerating the rate of healing and shortening recovery time.
Heavy exercisers are at higher risk for
being zinc deficient due to sweat that an athlete produces. Since sweat
contains relatively high amounts of zinc, increased sweat excretion of zinc
occurs during heavy exercise. If an athlete is also eating a diet lacking zinc,
a zinc deficiency ensues. In disorderition to sweating, frequent consumption of
highly refined sugar foods or alcohol will cause increased urinary excretion of
zinc.
While zinc deficient, the athlete becomes
prone to injury. Tissues that are stressed will not recover during normal
resting periods. This means that muscles or connective tissue are weakened and
in an injury prone state.
Immune Function
Another important body function that is
affected by zinc is immunity. Great concern for a healthy immune system has
been stimulated by the AIDS epidemic. Zinc is the most important mineral for
the immune system. A zinc deficiency causes a dramatic impairment in the body’s
ability to properly respond to foreign invaders. It reduces the number of white
blood cells available to attack bacteria, virus and yeast. Dr Prasad MD PhD,
the discoverer of zinc deficiency, has commented that a zinc deficiency will
produce an overgrowth of the yeast, Candida albicans.26 ,27 Where
Candida albicans, viral or bacterial infections are a concern, zinc status
should be checked.
Dr Chandra, in his scientific journal,
Nutrition Research, has demonstrated that a zinc deficiency produces an
immunological defect very similar to that seen in AIDS patients. To be sure
that the immune system is healthy, an individual needs to have adequate body
stores of zinc.
Skin problems
Seborrhoea, scaling or flaking of the skin
can be the result of a zinc deficiency. Acne and various other rashes or
discoloration researchers. Those concerned about gaining healthy, clear skin
could with benefit check their zinc status.
Taste
Loss of taste and appetite are associated
with zinc deficiency. Zinc plays a very important role in the taste function.
Therefore, those who notice their foods are notas tasty as previously, and
those who have lost their appetites should be alert to the possibility of zinc
deficiency.
Anorexia
Dr. Bryce-Smith of Reading University in
England and Alex Schauss of the Biosocial Research group in Seattle, Washington
have correlated zinc deficiency with a loss of appetite and a loss of taste
perception in anorexia nervosa and bulimia.28 In studies published in
the Lancet by Dr Bryce-Smith, anorexic patients have been identified
with the oral Zinc Taste Test to be zinc deficient.29 Supplementation
with zinc has led to a complete remission in some anorexics. This, and other
studies, demonstrate the powerful effect that zinc deficiency can have, not
only on physical conditions of the body, but also on behaviour.30 31
A recent case history was reported by Alex
Schauss. A severely mentally ill patient, suffering from hyperphagia, a mental
disorder in which the individual eats anything including their own faecal
matter and other obnoxious materials, responded to zinc. This person was tested
with the oral Zinc Taste Test and was found to be zinc deficient. Within one
week after administering the Zinc Taste Test solution as a supplement, this
mentally ill person stopped her aberrant eating habits and began normal eating
patterns. Interestingly, this patient was taking a zinc supplement before using
the Zinc Taste Test solution. This emphasises the importance of proper
absorption of zinc, and that some forms of zinc supplements are not well
utilised by the body.
Sex, zinc and the prostate gland
Another effect of zinc deficiency is a
decrease in sexual function of men. Gradual loss of zinc will ultimately
produce sexual impotency, which may include a loss of sex drive as well as an
inability to manufacture proper amounts of sperm, or infertility. For the male
experiencing disinterest in sex, zinc deficiency should be considered as a
possible cause.
The prostate gland, which commonly
malfunctions in old age, is also dependent upon normal zinc levels. In the
absence of zinc, the prostate can swell and produce a variety of unusual
symptoms (for example, the need to urinate in the middle of the night). Men who
cannot sleep through the night without urinating may simply suffer from a zinc
deficiency. When the prostate gland is not functioning correctly, an individual
is incapable of holding urine in the bl disorderer without feeling the urgency to
urinate frequently. Prostate problems may also affect a man’s sex drive.
Intestinal repair
Normal bowel function is also dependent
upon zinc. People suffering from bowel diseases, Crohn’s Disease, colitis and
chronic constipation have been found to have low levels of zinc. Zinc
deficiency is also associated with diarrhoea.
Iron, copper and zinc
High doses of supplemental zinc over a
prolonged period can displace other minerals, specifically copper and iron.
This can result in serious copper and iron deficiency symptoms such as elevated
cholesterol, hypochromic macrocytic anaemia32 and mood alterations. An
absorption enhanced zinc supplement can be administered at lower dosages and
accomplish its therapeutic goal while minimising the risk of mineral
imbalances.
Summary
Vitamin B6 is
required for the production of picolinic acid from tryptophan. Picolinic acid
is secreted into the lumen of the intestine, where it co-ordinates with zinc to
form a complex that facilitates the passage of zinc through the
gastrointestinal wall and into circulation. The quantity of zinc transported
into the blood is directly related to the availability of picolinic acid. The
availability of picolinic acid, therefore, depends upon normal pancreatic
function and proper dietary levels of tryptophan and vitamin B6.
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