Zinc, a dietary essential trace element, is primarily an intracellular metal involved in numerous metabolic processes, i.e., as a catalyst, structural element, or regulatory ion. Zinc is involved in the major metabolic pathways contributing to the metabolism of proteins, carbohydrates, energy, nucleic acids and lipids. Needed for enzyme activities, essential for the body’s normal function and development as it helps in the making of new cells and enzymes, zinc also plays a crucial role in the protection and repair of DNA and helps to regulate hormone levels. Most zinc is lost when food is processed, and a lack of zinc is linked to poor growth and infertility.
Vital for growth and wound healing, zinc is also a powerful antioxidant and immune system booster, helping to protect the body from infection. It is also thought to be important for brain function and a healthy nervous system, and is important for mental alertness.
Zinc is crucial for healthy reproductive organs both for men and women. It is needed for the production of healthy semen, helps form genetic material and is crucial for the development of a healthy fetus. It also helps to maintain your senses of sight, taste and smell.
Phytate is the major dietary factor that influences zinc absorption in the body. Phytate can bind zinc in the intestinal lumen and form an insoluble complex that cannot be digested or absorbed because humans lack the intestinal phytase enzyme. This inhibitory effect on zinc absorption in adults can be substantial because there is no evidence of an adaptive response to habitual high-phytate intakes. Zinc deficiency in humans is known to be an important malnutrition problem world-wide.
Zinc deficiency symptoms:
● Frequent infections
● Poor wound healing
● Loss of sense of taste or smell
● Eczema or psoriasis
● White flecks in the fingernails
● Poor appetite
● Slow nail and hair growth.
Some conditions associated with an increased risk of zinc deficiency
● Gastrointestinal and metabolic disorders:
◦ inflammatory bowel disease, ulcerative colitis, Crohn disease, malabsorption syndrome
◦ chronic liver or renal disease, diabetes, malignancies, and other chronic illnesses
◦ chronic diarrhea/tropical enteropathy leading to excessive zinc loss
● Vegetarian diet
● Pregnancy and lactation [the RDA for zinc is higher for pregnant and lactating women than for other women]
● Hemoglobinopathies (sickle cell disease/thalassemia)
Colds and flu – As one of the main protectors of your immune system, zinc is important to help fight infection. In tests, sucking zinc lozenges reduced the length and severity of illnesses such as colds and flu significantly.
Healthy skin- Zinc reduces inflammation, and supplements are beneficial for treating acne and other skin complaints such as eczema. Extra zinc speeds up wound healing.
Arthritis – As an antioxidant and immune system booster, zinc can help to reduce pain and inflammation.
Infertility – women with irregular periods may benefit from zinc supplements. Zinc is useful in cases of male subfertility because it is important for healthy sperm production and increases potency and sex drive.
High doses of zinc reduces the amount of copper the body can absorb and also interfere with the production of healthy blood cells leading to anemia and weakening of bones. Amounts up to 25 mg a day are thought to be safe for short term use; so if you take zinc supplements, do not take too much as it could be harmful and consult your doctor or pharmacist first.
According to the NHS, the amount of zinc needed per day for adults males is 9.5mg and 7mg for women. You should be able to get the zinc you need from a varied and balanced diet.
Because there is no functional reserve or body store of available zinc, except possibly in infants, a regular, adequate dietary supply is required.
Good sources of zinc in the diet include meat (steaks for example), shellfish (oysters), cereal products (such as wheatgerm), pumpkin seeds, fish, brazil nuts, egg yolk, milk and dairy foods such as cheese.
● Antibiotics: both quinolone antibiotics (such as ciprofloxacin) and tetracycline antibiotics have been reported to interact with zinc in the gastrointestinal tract, causing a reciprocal and negative impact on the absorption of both zinc and the antibiotics.
● Penicillamine: the absorption of penicillamine, a drug used for treatment of Wilson disease (genetically mediated copper excess) and rheumatoid arthritis, was reduced by zinc supplements.
● Diuretics: urinary zinc excretion is increased and plasma zinc concentrations decrease with the use of diuretics.