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7+ Signs of Zinc Deficiency and the Best Foods to Reverse It!
March 31, 2024
One epidemic that most folks in the U.S. are probably unaware of is zinc deficiency. A significant problem for most countries in the world, the World Health Organization (WHO) reports that the global prevalence of zinc deficiency may be as high as 31 percent.
Living in our American bubble of fortified foods and multivitamin supplements at virtually every supermarket in the country, we are generally out of touch with global health problems that affect literally millions of people every day, but zinc deficiency is a concern in the the United States as well.
We know that zinc benefits our health and is essential for proper body function. However, we often fail to realize that just because we are eating foods with added nutrition doesn’t mean that our bodies are absorbing it, and there are many zinc deficiency risk factors right here in the U.S.
Even people living in developed, industrial nations aren’t immune to zinc deficiency.
Zinc Deficiency Worldwide
Data shows that zinc deficiency is one of the most common micronutrient deficiencies in the world. Along with low levels of iron, iodine, folate and vitamin A, zinc deficiency is a common contributor to poor growth, intellectual impairments, perinatal complications, and increased risk of morbidity and mortality, according to research published in Annals of Nutrition & Metabolism.
Zinc deficiency is such a serious global problem that it’s responsible for roughly 176,000 diarrhea deaths, 406,000 pneumonia deaths and 207,000 malaria deaths — primarily in Africa, the Eastern Mediterranean and South-East Asia.
What is a zinc deficiency exactly?
Everyone, young and old, requires regular zinc intake to remain alive, which is why it is referred to as an “essential” trace element. Even plants and animals need it to survive! It’s present in every cell, organ, bone, tissue and fluid in the body.
When you don’t consume enough foods high in zinc, you are in danger of zinc deficiency and serious symptoms like weakened immunity and cognitive function.
Symptoms
Unfortunately, millions of people are zinc deficient and are completely unaware of their condition. Thankfully, if you keep a look out for some key indicators, you can catch a zinc deficiency early, before it has a major impact on your overall health.
The seven most common zinc deficiency symptoms that you should be aware of include:
1. Poor Neurological Function
Absolutely essential for growth and neuropsychologic performance, low zinc levels have been linked to attention and motor disorders in infants that persist well into adulthood.
In fact, a review published in 2023 determined that “zinc deficiency may result in declines in cognition and learning and an increase in oxidative stress.”
2. Weak Immunity
Zinc is also absolutely essential to maintain immune function. Specifically, it is vital for:
- T-cell growth and differentiation into the white blood cells that we need to ward off disease
- Apoptosis (“programmed cell death”) to kill dangerous bacteria, virus and cancer cells
- Gene transcription, the first step of gene expression
- Protective functions of our cell membranes
Zinc is also a key structural component for a slew of hormone receptors and proteins that contribute to healthy, balance mood and immune function.
3. Diarrhea
Most likely due to the impaired immunity that is caused by zinc deficiency, infectious, persistent diarrhea is a major public health concern. Affecting nearly 2 million children in developing countries every year, these children become more susceptible to E. coli and other bacterial infections.
Zinc supplementation has been found to be effective at treating babies older than 6 months. Be sure to consult with your pediatrician before giving zinc to your infant.
4. Allergies: Food and Environment
Chronic stress can cause adrenal fatigue and can lead to calcium deficiency, magnesium deficiency and zinc deficiency, which contributes to elevated histamine levels. Zinc is a key factor in how your body stores histamine.
Since the micronutrient is required to store histamine, zinc deficiency allows more histamine to be released into the surrounding tissue fluids. This is important for two reasons:
- Excess histamine in your body will produce many of the common symptoms associated with allergies (running nose, sneezing, hives, etc.).
- High histamine levels increase one’s sensitivity to all allergic reactions.
5. Thinning Hair
Maybe you’ve heard about zinc deficiency hair loss in the past. Well, there may be a connection here, according to researchers.
A common complaint of people battling adrenal fatigue, zinc deficiency is associated with hypothyroidism, which is an overlooked cause of thinning hair and alopecia.
According to Indian researchers, thyroid hormones are essential for zinc absorption. Subsequently, hypothyroidism-caused hair loss may not improve with thyroxine unless zinc supplements are added.
6. Leaky Gut
The gut-skin connection describes how leaky gut (also referred to as intestinal permeability) can cause a slew of health conditions, including nutrient malabsorption, skin disorders, allergies, autoimmune disease and thyroid problems.
Shown clinically to help resolve permeability alterations, zinc supplementation can actually “tighten” leaky gut in Crohn’s patients.
7. Acne or Rashes
Just like the way leaky gut causes various skin issues, some people will develop skin rashes and even acne when they don’t have sufficient zinc levels. Research also shows that zinc deficiency is associated with delayed wound healing and other skin manifestations.
Other common zinc deficiency symptoms include:
- open sores on the skin
- unexplained weight loss
- loss of appetite
- wounds that won’t heal
- decreased sense of taste and smell
- lack of alertness
- skin ulcers
- worsened asthma symptoms
- frequent colds
- vision issues
- depression
- sexual dysfunction
- eye and skin lesions
- lethargy
Causes and Risk Factors
Maybe you are at risk of zinc deficiency and wondering, “Do I need a zinc supplement?” The people with the following health conditions are most susceptible to zinc deficiency.
- Alcoholism: Linked to poor zinc absorption, a history of long-term, excessive alcohol use puts people at a considerable risk of developing zinc deficiency.
- Diabetes: Most doctors agree that diabetics should use zinc products cautiously because large doses can dangerously lower blood sugar.
- Hemodialysis: Hemodialysis patients are also at risk for zinc deficiency and might require zinc supplements.
- HIV (human immunodeficiency virus)/AIDS: Linked to shorter life spans, zinc should be taken cautiously in HIV/AIDS patients.
- Nutrient absorption syndromes: Malabsorption syndromes put people at a greater risk of zinc deficiency.
- Rheumatoid arthritis (RA): RA patients absorb less zinc and may require supplementation.
Not as prevalent, the Linus Pauling Institute reports that these people are also at risk:
- Premature and low-birth-weight infants
- Older breastfed infants and toddlers with inadequate intake of zinc-rich foods
- Pregnant and lactating women
- Patients receiving intravenous feedings
- Malnourished individuals, including those with eating disorders
- Individuals with severe or persistent diarrhea
- Individuals with inflammatory bowel disease
- Individuals with chronic renal disease
- Individuals with sickle cell anemia
- Individuals who use medications, including tetracycline and quinolone antibiotics, as well as bisphosphonates
- Older adults (65 years and older)
- Strict vegetarians: The requirement for dietary zinc may be as much as 50 percent greater for strict vegetarians whose major food staples are grains and legumes, because high levels of phytic acid in these foods reduce zinc absorption.
Diagnosis (Zinc Deficiency Test)
A zinc blood test can be taken to detect a zinc deficiency. A health care professional can test your blood plasma for zinc levels. A normal serum zinc level is between 0.66 and 1.10 mcg/mL.
Zinc deficiency tests can also be done with a urine sample and hair analysis.
Zinc tests can also measure elevated serum zinc levels, although research suggests that this is of minimal clinical interest because it’s a rare occurrence.
High zinc levels can lead to issues like nausea, dizziness, vomiting and chest pain. Taking too much zinc or being exposed to zinc through cleaning products, pains and varnishes can be problematic.
Treatment
The best way to avoid zinc deficiency and maintain sufficient zinc serum levels is to consume foods high in zinc regularly. The best sources of zinc are animal foods because the essential mineral’s bioavailability, which is the fraction of zinc that’s retained and used by the body, is highest in animal meats, seafood and eggs.
Zinc is also found in grains, legumes, fruits and vegetables. These sources of zinc are less bioavailable because of their phytic acid content.
That being said, research suggests that people who do not eat meat, like those on a vegetarian or vegan diet, can maintain proper zinc levels by consuming up to 50 percent more zinc in their diets in order to absorb what the body needs. Methods such as soaking, heating, sprouting, fermenting and leavening grains and legumes can also help improve zinc absorption.
For people who aren’t eating enough absorbable high-zinc foods or have digestive issues that don’t allow for the proper absorption of the mineral, taking a zinc supplement may be beneficial.
Zinc supplements generally contain several forms of zinc, including zinc acetate, zinc gluconate and zinc sulfate. The percentage of elemental zinc varies by form. According to the National Institute of Health (NIH), “Research has not determined whether differences exist among forms of zinc in absorption, bioavailability or tolerability.”
Zinc gluconate is the most common over-the-counter zinc supplement that can be found in your local drug store. Zinc gluconate and zinc acetate are often added to cold remedies, including nasal sprays and lozenges.
Research published in American Family Physician suggests that zinc supplementation “may be effective for the prevention of upper respiratory infection and diarrhea,” and zinc in combination with antioxidants may be modestly effective in slowing the progression of age-related macular degeneration.
Recommended Zinc Dosage
Although severe zinc deficiency is quite rare, the Linus Pauling Institute estimates that up to 2 billion people are affected by marginal zinc levels, which can affect virtually every aspect of your health.
The recommended dietary allowances (RDAs) for zinc are as follows:
* Adequate Intake (AI)
It’s important to note that because the developing fetus and infant require zinc, pregnant and lactating women should consciously increase their zinc intake so their babies will not suffer any harm.
These numbers above are the daily intake for regular maintenance levels of zinc. If you are treating a zinc deficiency, try taking 30 milligrams of zinc per day for 90 days. Also make sure to include a daily supplement that contains copper over this time frame.
Zinc taken for longer periods can deplete your copper levels, so you want to be conscious of that factor.
Risks and Side Effects
Most health authorities agree that it’s likely unsafe to consume elevated amounts of zinc for extended periods of time. Doing so can cause coughing, fatigue, fever, stomach pain and a number of other health problems.
If you are trying to reverse zinc deficiency in adults or children, you need to consult with a health care professional to avoid consuming too much zinc in the process.
Regularly taking 450 milligrams or more of zinc each day has also been known to affect the level of iron in your blood, and taking too much zinc can also affect your copper levels.
In addition to this, here are some key recommendations for women:
- Pregnant women over 18 should limit their zinc intake to 40 milligrams per day.
- Pregnant women under 18 should limit their zinc intake to 34 milligrams per day.
- Breast-feeding women over 18 should limit their zinc intake to 40 milligrams per day.
- Breast-feeding women under 18 should limit their zinc intake to 34 milligrams per day.
Final Thoughts
- According to the World Health Organization, millions of people throughout the world may have inadequate levels of zinc in their diets.
- Zinc deficiency occurs when you don’t have enough zinc foods in your diet or you have trouble absorbing zinc from foods due to digestive disorders or very poor gut health.
- What happens when your zinc is low? A deficiency in zinc affects many organ systems, including the immune, gastrointestinal, skeletal, reproductive, integumentary and central nervous systems.
- If you are wondering if you need a zinc supplement and need to know the signs of a zinc deficiency, look out for issues like diarrhea, allergies, thinning hair, weak immunity and poor neurological function.