Zinc is an important trace mineral, which is useful for the body in many ways. It is essential for cell division and aids normal growth and development during pregnancy, childhood and adolescence.
It also helps in DNA synthesis, the process of genetic expression, immune system functioning, protein synthesis and metabolizing carbohydrates to convert them into energy.
The body contains about 2 to 3 grams of zinc, mostly in the skeletal muscles and bones. It is also found in the kidneys, pancreas, retinas, liver, blood cells, teeth, hair, skin, prostate and testes.
Though zinc is essential for good health and body functioning, its deficiency is prevalent in young children, pregnant women, breastfeeding mothers and the elderly.
According to the World Health Organization, 31 percent of people worldwide have a zinc deficiency at any given time.
The primary cause of zinc deficiency is insufficient nutrition. It can also be due to alcoholism, bariatric surgery, diabetes and other disorders.
Here are the top 10 signs of zinc deficiency.
1. Compromised Immunity
Zinc is essential for the immune system to function properly, and its deficiency can cause reduced or weakened antibodies and low immunity. Zinc is important for T-cell growth and improving the protective functions of cell membranes.
A 2002 study published in the European Journal of Clinical Nutrition clearly indicated that this trace element has a broad impact on key immunity mediators, such as enzymes, thymic peptides and cytokines.
People who have zinc deficiency are more prone to infection, the common cold and flu. Small babies and elderly people, who usually have low immunity, must pay extra attention to eating zinc-rich foods.
2. Persistent Diarrhea
Zinc deficiency also contributes to an increased incidence and severity of diarrhea. It causes low immunity and alters the body’s immune response that probably contributes to increased susceptibility to infections that cause diarrhea, especially in children.
It can even cause other gastrointestinal diseases, such as ulcerative colitis, Crohn’s disease and short bowel syndrome.
A 2000 study by the American Society for Nutritional Sciences reinforced the link between zinc deficiency, malnutrition and diarrheal disease.
In a 2012 study published in Cochrane Database of Systematic Reviews, researchers concluded that in areas where the prevalence of zinc deficiency is high, oral zinc supplements might be beneficial in children ages 6 months or older who suffer from diarrhea.
3. Loss of Appetite
A deficiency of zinc causes loss of appetite. The mechanism by which this occurs is unclear. However, it is believed that zinc affects neurotransmitters in various parts of the brain, including gamma-amino butyric acid (GABA) and the amygdala, which affect a person’s appetite.
A low zinc level in the body also interferes with your sense of smell and taste, which often leads to loss of appetite and weight loss.
A 2006 study published in the Eating and Weight Disorders journal found that oral administration of 14 mg of elemental zinc daily for 2 months helped in treating patients with anorexia nervosa (loss of appetite).
4. Poor Growth in Children
Zinc is critical for a child’s normal growth and development. This mineral is essential for cellular growth, cellular differentiation and metabolism. In fact, its deficiency can limit childhood growth and lower resistance to infections.
Lack of this mineral can even prevent children from reaching a healthy height and weight. It also causes delayed sexual maturation.
A 2014 study published in The Cochrane Collaboration journal suggests that zinc supplementation can be useful for preventing mortality, morbidity and growth failure in children ages 6 months to 12 years.
Breastfeeding is important for infants, as zinc is found in small amounts in breast milk.
5. Thinning Hair
Zinc deficiency weakens the cells on the scalp, leading to hair problems including alopecia, loss of pigment, dryness, brittleness, and hair shaft and structural abnormalities that cause fragility and breakage. Hairs in the eyebrows as well as eyelashes may also be affected.
In addition, a low zinc level is associated with hypothyroidism, which can cause thinning hair and alopecia. A 2013 study published in the International Journal of Trichology suggests that zinc deficiency is associated with hypothyroidism, an overlooked cause of severe alopecia.
Eating more zinc-based foods or taking zinc supplements can help treat hair-related problems. Always consult your doctor before taking supplements.
6. Skin Problems
Deficiency of this important trace mineral can also have a bad effect on your skin. It can contribute to acne, eczema, psoriasis, characteristic skin rashes called acrodermatitis enteropathica (especially around the mouth, eyes and anus), or dry scaly skin. The skin may even turn pale.
Zinc aids collagen synthesis, which is essential for healthy skin as well as healing of skin wounds. In addition, zinc helps in the proper structure of proteins and cell membranes and protects the skin from harmful ultraviolet (UV) radiation. It also lessens the formation of damaging free radicals.
Most health experts recommend applying zinc-based creams and lotions on the skin for treating acne, aging skin and herpes simplex infections as well as promoting wound healing.
7. Behavioral Disturbances
Zinc deficiency is common in a number of psychiatric disorders, including dementia, psychotic disorder and anxiety disorders. It is an anti-stress nutrient and is associated with emotional instability.
Its deficiency could lead to a reduction in serotonin synthesis and an increase in anxiety as well as frequent mood changes, anger, sudden fright, depression and low confidence. If not addressed timely, it may even lead to attention deficit hyperactivity disorder (ADHD).
A 2011 study published in the Progress in Neuro-psychopharmacology & Biological Psychiatry journal highlights the role of zinc in neurodegenerative inflammatory pathways in depression.
In addition, a 2010 study published in the Current Opinion in Clinical Nutrition & Metabolic Care journal reviewed several studies on zinc and mood disorders and concluded that an adequate zinc level in the body helps reduce symptoms of depression and anxiety.
8. Vision Problems
According to the American Optometric Association, zinc is essential for vision. High levels of zinc are present in the macula, which is part of the retina.
It enables vitamin A to create melanin, a pigment that protects the eye and even helps you see better at night. Its deficiency can result in poor night vision and cloudy cataracts.
A 2001 study published in the Archives of Ophthalmology suggests that antioxidant and/or zinc supplements may delay progression of age-related macular degeneration (AMD), a leading cause of vision loss among older people.
People who have a risk of developing AMD should consult their doctor about taking a zinc supplement.
9. Low Cognitive Function
Zinc deficiency can also cause damage to the neurological system, impairing your cognitive skills, such as learning and hedonic tone (general level of pleasantness or unpleasantness).
It is also associated with dyslexia, a learning disability. Zinc interacts with and modulates different synaptic targets, including glutamate receptors and voltage-gated channels, which play a key role in learning and memory.
Another study, published in the Biological Trace Element Research journal in 2013, suggests that oral zinc supplementation may improve cognitive function in school-age children.
10. Weak Bones and Joints
Zinc is a vital bone nutrient and its deficiency can greatly affect your bones and it helps in the stimulation of bone-building osteoblasts. A deficiency of this mineral often causes joint pain.
A 2010 study published in the Nutrition Research and Practice journal suggests that zinc might increase bone formation through stimulating cell proliferation, alkaline phosphatase activity and collagen synthesis in osteoblastic MC3T3-E1 cells.
As the amount of zinc in the bones declines with age, taking zinc supplements can help maintain bone health and reduce the risk of arthritis. Consult your doctor before taking any supplements.
Tips to Treat Zinc Deficiency
Zinc deficiency can be easily corrected with dietary sources. Some good sources of zinc are:
- Red meat, poultry and eggs
- Oysters, crab, lobster and other shellfish
- Pulses, baked beans, chickpeas and legumes
- Nuts and seeds like cashews, almonds, sesame seeds and pumpkin seeds
- Whole-grain cereals
- Fortified breakfast cereals
- Dairy products like cheese and low-fat milk
You can also take zinc supplements, but only after consulting your doctor.
Note: Avoid high zinc intake, as it can lead to zinc toxicity causing symptoms like nausea, vomiting, loss of appetite, abdominal cramps, diarrhea and headaches.