Zinc: An Essential Nutrient for Health

While vitamin C usually wins the popularity contest for immune boosting supplements, zinc should be listed just as high on the list.

But beyond immune health, zinc is present in every cell in the body, playing a role in many critical cellular functions from DNA synthesis to skin integrity.

However, taking zinc supplements long-term is not necessarily a great idea and can negatively impact your health.  So before you fill up your online cart, make sure you understand what zinc is and when it may be appropriate to consider supplementation.

What is zinc?

Zinc an essential micronutrient (meaning your body needs to obtain it from food or supplements because you can't make it yourself).  Specifically, zinc is a trace mineral that works as a catalyst for hundreds of important enzymatic reactions in the body. It acts as an antioxidant to decrease inflammation in the body.  And yes it supports the immune system, but it also plays a role in gene expression, and is even necessary for protein synthesis and wound healing.  

While outright zinc deficiency is less common in developed countries, even suboptimal zinc status can cause health concerns.  Zinc deficiency in children can cause growth issues, but even slight deficiencies are associated with infertility, mood disorders, and dry skin.

Where is zinc found?

Ideally you can obtain all the zinc you need from eating a well-balanced diet without the need for supplementation.  Foods highest in zinc include:

• Meat, poultry, and fish

• Oysters and shellfish

• Eggs

• Nuts and seeds

• Legumes

• Dairy

While zinc is present in grains, these sources are also high in phytates.  Phytates are compounds found in grains that can inhibit absorption of certain nutrients like zinc.  As a result, animal-based foods tend to be the most bioavailable sources of zinc because we can easily digest and absorb them.

While most people get plenty of zinc in their diet, people who are at risk for deficiency include:

• Vegetarians or vegans

• People with GI diseases that interfere with absorption

• Breastfed infants if the mother has suboptimal zinc status

• Pregnant or breastfeeding women

• People who drink alcohol heavily

• Athletes who don’t replenish (zinc is lost through sweat)

• People with insulin resistance

How can zinc supplementation help our health?

Studies on zinc supplementation are designed for short-term interventions.  Since most people can get adequate zinc from their diets, supplementation is intended for those who may be deficient or for specific therapeutic amounts to support a condition (like boosting the immune system).  This is important to keep in mind when discussing the benefits of zinc supplements as many of the studies specifically look at people with low zinc status to see how improving the levels can be beneficial.

For example, zinc supplementation may support better blood sugar control for people with insulin resistance.  Studies have shown that people with insulin resistance or blood sugar dysregulation may also have a zinc deficiency.  Zinc appears to play a role in the synthesis and signaling of insulin (the hormone needed to balance our blood sugar).  

But the reason most people supplement with zinc is to help them recover more quickly from getting sick.  High doses of zinc may help decrease the amount of time you are sick (by up to 40%) and possibly help prevent you from getting sick in the first place.  Many of the studies specifically look at zinc lozenges in higher doses to help cut the time you are sick by a few days, especially easing symptoms of sore throat or nasal congestion.  It also can help reduce infections, particularly in older adults or other vulnerable populations.

Zinc has also been studied for its potential role in helping with depression.  Low levels of zinc are associated with depression, and studies have found that zinc in combination with an antidepressant improves outcomes.

Another interesting way zinc supplementation may help is by supporting male fertility.  While women are commonly the center of fertility interventions, zinc can act as an antioxidant and support healthy hormone balance for men.

Zinc carnosine is also commonly used to heal the GI tract, specifically for intestinal permeability, reflux, and ulcers.

Adequate zinc is necessary for wound healing and skin integrity, and it may also help with acne-prone skin.  Some research suggests that taking zinc supplementation can help improve acne.  Again this is more beneficial for people who are already deficient.  It can decrease inflammation and bacteria growth related to acne.

Should you supplement with zinc?

Part of the reason it's essential to take zinc short-term, or if you are deficient, is that taking too much zinc can cause copper or iron deficiency because it can inhibit absorption.  

Zinc can also cause an upset stomach or nausea, as well as changes in taste or smell.

If you consider supplementing with zinc, the first thing you should do is have a conversation with your doctor or dietitian.  The best way to take advantage of zinc's health benefits is to make sure you get enough through your diet.  If you are someone who is on the list of being at risk for a deficiency, then you can consider supplementation but be mindful of copper and iron in your diet as well.

Supplementation for immune health, especially to help with symptoms of a cold seems to be well-researched, but always remember that zinc supplements should be used short-term.

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