Zinc Deficiency

What is zinc?

Zinc is a mineral that plays an important role in many different chemical reactions in your body. The human body uses this mineral to fight off infections, maintain acid-base balance, promote growth and development, boost antioxidant activity, and regulate gene expression, among others.

What happens if my zinc is low?

If you do not get enough zinc in your diet, you may experience certain side effects, such as, decreased alertness, impaired sense of smell and taste, and hair loss. Although zinc deficiency is rare in the US, it still occurs in some people.

Other symptoms of zinc deficiency include:

• Poor wound healing
• Lethargy
• Deformed nails
• Canker sores
• Low libido in men
• Roughened skin or rash
• Loss of appetite
• Weight loss
• Growth retardation
• Impaired immune function

People with malabsorption problems, severe diarrhea, alcoholism, or liver cirrhosis might also develop zinc deficiency. This mineral deficiency may also occur after undergoing a major surgery and in people receiving long-term enteral nutrition (tube feeding) in the hospital. Zinc levels may be restored by giving zinc through IV or orally taking zinc. However, the regular intake of zinc through supplements is not usually recommended.

Zinc also plays a significant role when it comes to maintaining vision, as this mineral is found in high concentrations in the eye. Low zinc levels can impair a person’s vision, and being severely deficient in zinc can cause changes in the retina.

Although researchers still cannot exactly explain how zinc works against certain viruses, zinc seems to reduce the symptoms of the common cold, which is caused by rhinoviruses. Moreover, there are some evidence of zinc having antiviral properties against the herpes virus.

Low levels of zinc are also associated with major depression, male infertility, type 2 diabetes, HIV, and sickle cell disease. These conditions can be fought by zinc supplementation. 

Risk Factors

Zinc deficiency often occurs due to an increased zinc requirement, inadequate intake or absorption of zinc, or increased loss of zinc from the body. People who are at risk of zinc deficiency might need supplemental zinc in certain situations, aside from incorporating rich sources of zinc in their regular diet. 

People with digestive disorders and other diseases

Zinc absorption can be decreased in people with digestive disorders, such as Crohn’s disease, ulcerative colitis, and short bowel syndrome, including those who had undergone gastrointestinal surgery.

Other diseases that are associated with zinc deficiency include chronic kidney disease, chronic liver disease, malabsorption syndrome, malignancy, diabetes, and other chronic medical conditions. Excessive zinc loss can also be a result of chronic diarrhea. 

People diagnosed with sickle cell disease

Approximately 60-70 percent of adults diagnosed with sickle cell disease develop a deficiency in zinc. According to one study, low plasma zinc is common in children with sickle cell disease due to poor nutrition or increased nutrient requirement.

Children diagnosed with this condition have also shown an improvement in their growth through zinc supplementation. 

Alcoholics

Zinc levels in approximately 30-50 percent of alcoholics are low due to the consumption of ethanol, which decreases zinc absorption and increases the excretion of urinary zinc. 

Pregnant and breastfeeding women

One of the side effects of early pregnancy is mild to moderate zinc insufficiency due to high zinc requirements of the fetus. Maternal zinc stores can also be depleted during lactation.

Exclusively breastfed older infants

For the first 4-6 months of life, infants can get around 2 mg of zinc through breast milk. However, breast milk cannot provide enough amounts of zinc for older infants (7-12 months old), who need 3 mg of zinc per day. For this reason, older infants should be eating age-appropriate foods or milk formula that contains zinc aside from consuming breast milk.  

Vegetarians

Since vegetarians do not eat meat, which contains bioavailable zinc, their levels of zinc in the body tend to be lower than those who consume non-vegetarian diets. Additionally, vegetarian diets typically consist of whole grains and legumes, which contain phytates that bind and inhibit the absorption of zinc. 

Where can I get zinc?

There are many dietary sources of zinc available. Some of its best sources are nuts, seeds, legumes (peas, beans, and lentils), meat, seafood, and dairy products. Most multivitamins including a wide variety of dietary supplements also contain zinc.

When taking supplements or multivitamins with zinc, it is recommended to take them with a high-protein meal for better absorption. However, those with fat malabsorption problems may be better off taking zinc on an empty stomach. 

It is also important to note that taking high doses of zinc for a long period of time can cause toxicity and side effects. When taking supplemental zinc, make sure to ask your doctor about its recommended dosage and length of time. Taking supplemental zinc can also deplete copper in the body. 

Diagnosing Zinc Deficiency

Zinc levels can be difficult to measure using laboratory tests due to the wide distribution of zinc throughout the body.

However, if your healthcare provider suspects a deficiency in zinc, a blood plasma test may be ordered for accurate results. Other tests may include hair analysis for zinc content and a urine test.

In some cases, having low levels of zinc may be a symptom of an underlying medical condition. Copper deficiency can also result from zinc deficiency. Additional testing may be needed to determine the main cause of your mineral deficiency. 

Treatment

Zinc deficiency treatment involves dietary changes. To help increase your zinc levels, try consuming more of the following:

• Nuts and seeds
• Wheat germ
• Poultry
• Red meat
• Oysters
• Wild rice

Vegetarians may want to consider consuming peas, almonds, cashews, and baked beans as their alternative sources of zinc. To help prevent zinc deficiency, The United States Department of Agriculture (USDA) provides a comprehensive list of zinc-rich foods that you can include in your diet. 

Zinc supplements can also be used in treating zinc deficiencies. However, be careful when using supplements that boost the levels of zinc in your body because zinc can also interact with certain drugs, such as antibiotics, diuretics, and medications for arthritis. 

References

Zinc Fact Sheet for Consumers. (February 2016). https://ods.od.nih.gov/factsheets/Zinc-Consumer/

Zinc Fact Sheet for Health Professionals. (September 2018). https://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/

Zinc. (May 2018). https://medlineplus.gov/druginfo/natural/982.html

Prasad AS. Zinc: an overview. Nutrition. (1995)

Leonard MB., et. al. Plasma zinc status, growth, and maturation in children with sickle cell disease. J Pediatr. (1998)

Shrimpton, R., et. al. Zinc deficiency: what are the most appropriate interventions?­ BMJ. (2005)