Zinc deficiency in human subjects.

Area of Science:

• Human Nutrition
• Biochemistry
• Cell Biology

Background:

• Zinc essentiality in humans established over two decades.
• Zinc deficiency recognized in nutritional and disease states.
• High phytate content in cereals reduces zinc bioavailability.

Purpose of the Study:

• To summarize the established essentiality of zinc in humans.
• To outline the causes and manifestations of zinc deficiency.
• To highlight the biochemical roles of zinc.

Main Methods:

• Literature review of established knowledge on zinc.
• Identification of conditions leading to zinc deficiency.
• Summary of clinical manifestations and biochemical functions.

Main Results:

• Zinc deficiency linked to diet (high phytate), alcoholism, malabsorption, liver cirrhosis, renal disease, and sickle cell anemia.
• Manifestations include growth retardation, hypogonadism, skin changes, poor appetite, lethargy, delayed wound healing, taste abnormalities, and impaired dark adaptation.
• Severe deficiency can lead to dermatological issues, diarrhea, alopecia, mental disturbances, infections, and can be fatal.
• Zinc is crucial for spermatogenesis and testosterone production.
• Zinc-dependent enzymes are vital for DNA and RNA synthesis and metabolism, affecting protein synthesis.
• Alkaline phosphatase, carboxypeptidase, and thymidine kinase are highly sensitive to zinc restriction.

Conclusions:

• Zinc deficiency has diverse causes and significant clinical manifestations.
• Zinc plays a critical role in cellular processes, including nucleic acid metabolism and enzyme function.
• Adequate zinc levels are essential for normal growth, immune function, reproductive health, and overall well-being.