Zinc

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An essential trace mineral, probably most widely known for the integral role it plays in your immune system and the prevention and treatment of the common cold. Aside from iron, zinc is the most common mineral found in your body, necessary for the function of every one of your cells. Zinc is used in the production of white blood cells, helping your body to fight infection, and plays a key role in regulating the way your heart muscle uses calcium to trigger the electrical stimulus responsible for your heartbeat.1 It’s also one of the building blocks for approximately 3,000 proteins and 200 enzymes in your body. Recent research has now identified the role zinc plays in protecting your DNA.2 However, while essential, your body does not store zinc, so it is important you get enough from your dietary intake every day. Moreover, regularly getting too much can be just as hazardous as getting too little.

The American Journal of Clinical Nutrition shows that zinc supplementation is correlated with better skin healing outcomes in burn patients. Another study in American Journal of Clinical Nutrition demonstrates that zinc supplementation is beneficial in improving immune function in the elderly, specifically T cell function. The prestigious journal Pediatrics shows zinc supplementation reduces the incidence and recurrence of severe diarrhea in children. Behavioral Brain Research indicates that zinc supplementation has a positive effect on cognitive performance, specifically in short- and long-term recognition memory and spatial working memory. Zinc also lessens severity and duration of pneumonia and improves glycemic control in Type II Diabetes.

Zinc May Reduce DNA Strand Breaks

DNA is in every cell of your body and is the blueprint your cells use during replication. Until late adulthood your body has the ability to regenerate DNA, but over time DNA does deteriorate, eventually causing the overall breakdown of body systems. Recent research has identified the role zinc may play in slowing this DNA deterioration.

The National Institutes of Health (NIH) has determined a recommended daily amount of identified vitamins, minerals and nutrients that reduces the risk of experiencing symptoms of deficiency. However, a lack of symptoms of insufficiency does not necessarily support optimal health.

The levels recommended for zinc vary with age and gender as the absorption, use and requirements for the mineral varies with those same factors.

Researchers from the University of California San Francisco (UCSF) Benioff Children’s Hospital Oakland Research Institute (CHORI) began a study with the intention of measuring the impact small increases in dietary intake of zinc would have on the body’s metabolic functions.

Janet King, Ph.D., led the study where 18 men ate a rice-based, low-zinc diet for six weeks. Both before and after the experimental period the researchers measured indicators such as DNA damage, oxidative stress and DNA inflammation.3

When participants increased dietary zinc consumption researchers found a reduction in leukocyte DNA strand breakage, suggesting a modest increase in dietary zinc could reduce the everyday “wear and tear” on DNA. King commented:4

“We were pleasantly surprised to see that just a small increase in dietary zinc can have such a significant impact on how metabolism is carried out throughout the body.

These results present a new strategy for measuring the impact of zinc on health and reinforce the evidence that food-based interventions can improve micronutrient deficiencies worldwide.”

While increasing your dietary intake of zinc may be beneficial to your overall health, taking supplemental zinc may not be the way to accomplish your goal.

An Imbalance of Zinc and Copper May Lead to Health Problems

Your body has an elaborate system to maintain balance between trace minerals in your system, such as iron, zinc, copper and chromium. Consuming these minerals in your food helps maintain the proper balance, while taking supplements can easily create an imbalance of too much of one and not enough of another.

Sometimes ingestion occurs knowingly, such as when you take a daily supplement, and other times you may unknowingly absorb more than the recommended daily allowance for a nutrient through another chemical source.

In 2011, researchers from the University of Maryland published a study that demonstrated a hazard of ingesting excess zinc from denture adhesive.5

Excess zinc may lead to a copper deficiency, as the absorption patterns in the gastrointestinal tract are similar. Competition for absorption may lead to an increase in zinc and a reduction in copper.

Too much zinc may lead to nausea, vomiting, stomach cramps, headaches and loss of appetite.6 Getting your zinc from your diet significantly reduces the potential of overdosing.

Copper deficiency can be the result of malabsorption, malnutrition or from an excess of zinc in your system.7 High intake of zinc may increase the creation of metallothionein, a cell protein in your intestines that binds to some metals and prevents absorption.8

These cells have a stronger affinity for copper than zinc. This produces a cycle in which the consumption of zinc triggers the development of metallothionein cells, which then decrease the amount of copper absorbed.

One of the more common symptoms of a copper insufficiency is anemia. In this case the anemia will not respond to an increase in iron, but rather improves with copper supplementation.9

Copper deficiency may also lead to an abnormal low white blood cell count (neutropenia), increasing your potential for infection. In such a case, you may take a zinc supplement to alleviate your cold, for example, thereby worsening your copper deficiency.

Other abnormalities related to copper deficiency include osteoporosis, infants born at low birth weight and loss of pigmentation in your skin.

Zinc Strengthens Your Immune System

Inadequate amount of zinc in your diet may increase your potential for infection. Without zinc, your white blood cells don’t function optimally and other processes in your immune system are affected as well. Neutrophils, phagocytosis, antibody production and even gene regulation in your lymphocytes are affected by zinc.10

Although scientists are continuing to study the exact cellular changes an adequate supply of zinc produces on your immune system, some studies indicate it may reduce the duration of your cold by as much as 50 percent, especially if you are deficient.11

Each year there are approximately 200 different viruses that make up the “common cold.” While zinc helps support your immune system, it also appears to have antiviral properties that prevent the virus from replicating and attaching to your nasal membranes.12

Researchers have also discovered that zinc may have other immune boosting properties that help your body have a strong first response at the onset of symptoms.13

The initial dose must be taken in the first 24 hours of symptoms to work well, and those taking zinc are less likely have symptoms last more than seven days while supplementing with zinc lozenges.

Adequate Dietary Zinc Intake May Help Prevent Some Diabetes Complications

Some experts estimate that as many as 12 percent of people in the U.S. are deficient in zinc, with as many as 40 percent of the elderly due to poor absorption and low dietary intake.14 Zinc plays a significant role in the reduction of oxidative stress and helping DNA to repair, especially as you age. According to Emily Ho, Ph.D., associate professor with the Linus Pauling Institute at Oregon State University:15

“Zinc deficiencies have been somewhat under the radar because we just don’t know that much about mechanisms that control its absorption, role, or even how to test for it in people with any accuracy.”

The role zinc plays in protection against oxidative stress may explain, in part, why diabetics who have higher levels of zinc experience a lower risk of cardiovascular disease.16

A recent collaborative study with researchers from New Zealand and Australia demonstrated those with zinc blood levels between 14 micromoles and 18 micromoles per liter had the lowest risk of heart disease.17 Optimizing your dietary zinc intake may also improve diabetic markers, such as better glycemic control and lower concentrations of lipids.

Zinc Is Vital to Sensory Organ Function

Taste, smell and vision are three sensory functions in which zinc plays a significant role. Both taste and smell are important to your appetite, so a deficiency may reduce your desire to eat. This can be substantially important in people who suffer from cancer. Zinc deficiency, and the resulting loss of appetite, can be the result of some chemotherapy drugs and radiation treatments used to treat cancer.

In a review of the literature, researchers found a diversity of taste disorders with zinc deficiency.18 Zinc is critical to the production of the metalloenzyme carbonic anhydrase (CA) VI.19 When there is a deficiency of zinc, this enzyme is not made in adequate amounts, leading to loss of taste and, subsequently, appetite.

Your taste and smell systems use CA VI as a growth factor, but it also plays a role in apoptosis, or cell death. If you have a zinc deficiency, apoptosis increases in your body and the cells in your taste and smell organs die abnormally quickly. With an overload of zinc there is another type of alteration that results in further apoptosis and death of those same cells.20

Zinc also works in combination with vitamin A to help your eyes sense light and send the appropriate nerve impulses to the brain for interpretation.21 Your retina, an important part of eyesight, is made of membranes rich in polyunsaturated fats.22 Reactive oxygen species (ROS) may initiate chain reactions of lipid peroxidation that injures the retina, and therefore your eyesight.

Researchers have found a moderate zinc deficiency increases the oxidative stress on the retina and suggest that zinc may be protective against lipid peroxidation of the retinal membranes.23 While oxidative stress on the retina has been demonstrated, the role zinc plays in macular degeneration with age has not been conclusively proven.24 Like other symptoms of zinc deficiency, these appear to be reversible when blood levels return to normal through an appropriate intake of real food.

Improve Your Zinc Intake With Real Food

In this short video, I discuss the importance of zinc to your health, the signs of zinc deficiency and how you may improve your zinc levels through your dietary choices. Vegetarians have a particular challenge as phytic acid in grains compete with the absorption of zinc and other nutrients, which doesn’t occur in meat and dairy sources of zinc.

If you have symptoms of a zinc deficiency and choose to use a supplement, ensure it is from a reputable company using best-practice, quality assurance methods. Independent verification of the raw materials is vital to confirm quality and assure it is free of lead and other heavy metals. The supplement should contain several different types of zinc, such as gluconate, citrate and chelate. Unless your clinician recommends otherwise, don’t go above 40 milligrams (mg) per day.

Since it’s easy to create an imbalance in your body when taking supplements of trace minerals, your most effective way of balancing your zinc levels is through eating real foods high in zinc, such as:25

Zinc Deficiency & the Best Foods to Cure it!

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 is 31%. (1)

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 every day. However, we often do not 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 US!  Even people living in developed, industrial nations aren’t immune to zinc deficiency!

Ranked as the fifth  leading risk factor in causing disease worldwide, underdeveloped nations regularly suffer from high mortality rates because of the connection that zinc deficiency has with childhood diarrhea and pneumonia. (2)

Zinc deficiency is such a serious global problem that 176,000 diarrhea deaths, 406,000 pneumonia deaths and 207,000 malaria deaths are caused by it; primarily in Africa, the Eastern Mediterranean and South-East Asia.

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! Present in every cell, organ, bone, tissue, and fluid in our bodies zinc is especially prominent in the male prostate gland and semen.

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. (3) The recommended daily intakes for people are: (4)

* 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 that their babies will not suffer any harm.

Treating Zinc Deficiency

These numbers above are the daily intake for a regular maintenance levels for zinc. If you are treating a zinc deficiency, then I recommend taking 30 mg 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.

Zinc Deficiency 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 it early before things turn sour fast. The 7 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 connected with attention and motor disorders in infants that persist well into adulthood. (36) A Chinese study published in the American Journal of Clinical Nutrition discovered that a zinc supplement providing just 50% of the recommended daily allowance improved attention. But don’t run out and pump your kids full of zinc just yet! (6) The research found that zinc is best absorbed with a proper balance of other nutrients, as found in whole foods, which is why it is so important to contact your natural health care physician for some much needed guidance should you suspect a zinc deficiency.

2. Weak immunity

Zinc is also absolutely essential to maintain immune function. (7) 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 deficience 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 coli and other bacterial infections. (8) Zinc supplementation, however, has only been found effective at treating babies older than 6 months. (9) So, be sure to consult with your pediatrician before giving zinc to your infant.

4. Allergies: Food & Environment

Chronic stress causes adrenal fatigue and can lead to calciummagnesium and zinc deficiency; which contributes to elevated histamine levels. (10) Zinc is a key factor in how your body stores histamine. So since it 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

A common complaint of people battling adrenal fatigue, zinc deficiency is associated with hypothyroidism, an overlooked cause of thinning hair and alopecia. (11) 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. (11)

6. Leaky gut

First described over 70 years ago, the gut-skin connection describes how leaky gut (“intestinal permeability”) can cause a slew of health conditions including: nutrient malabsorption, skin disorders, allergies, auto-immune disease, and thyroid problems. Shown clinically to help resolve permeability alterations, zinc supplementation can actually “tighten” leaky gut in Crohn’s patients. (12)

7. Acne or rashes

Going hand-in-hand with leaky gut causing various skin issues, some people will develop skin rashes and even acne in the absence of sufficient zinc. (3)

Zinc Deficiency Risk Factors

Are you at risk?  

The people with the following health conditions are most susceptible to zinc deficiency. (13)

  • 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 lifespans, zinc should be cautiously in HIV/AIDS patients.
  • Nutrient absorption syndromes: Malabsorption syndromes put people at a greater risk of zinc deficiency.
  • Rheumatoid arthritis: RA patients absorb less zinc and may require supplementation.

Not as prevalent, the Linus Pauling Institute reports that these people are also at risk: (3)

  • Premature and low-birth-weight infants
  • Older breast-fed infants and toddlers with inadequate intake of zinc-rich foods.
  • Pregnant and lactating (breast-feeding) women.
  • Patients receiving intravenous feedings.
  • Malnourished individuals, including anorexics and bulimics.
  • 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, may decrease absorption of both zinc and the medication, potentially reducing drug efficacy.
  • Older adults (65 years and older).
  • Strict vegetarians: The requirement for dietary zinc may be as much as 50% greater for strict vegetarians whose major food staples are grains and legumes, because high levels of phytic acid in these foods reduce zinc absorption

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