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Can You Take Too Much Zinc?

Taking too much zinc can have dangerous side effects and even result in a copper deficiency. Learn more from our experts.

Zinc is a very important mineral to consume in your daily diet because it helps support the immune system, supports growth, and can increase healing time following wounds [1]. Its ability to strengthen natural immunity has long made it a favorite for those seeking a natural remedy for cures, but lately, COVID-19 is the reason why zinc consumption in the US is higher than ever. In fact, some zinc manufacturers have reported as high as a 3,000 increase in sales as a result of the pandemic [2].

Unfortunately, despite its powerful potential, zinc overdose is possible. We need to watch our zinc intake because too much zinc can be toxic and even cause a copper deficiency. In this article, we'll review what foods contain zinc, recommended daily zinc intake, tips to consult your doctor to see if you need to supplement a zinc vitamin or should try something like Healthycell Immune Super Boost.

Zinc: Sources and Dosing

One of the most common questions among those taking zinc to boost their immune system is "Can you take too much zinc?" After all, it is used in over 100 chemical interactions that occur daily within the body [3]. Therefore, some assume that more zinc would be beneficial to the body. However, excessive amounts of this mineral can be dangerous and experts recommend monitoring foods containing zinc in your diet while also consuming a zinc supplement.

When taken in appropriate amounts, zinc is used by the body to improve taste perception, DNA synthesis, encourage growth, support healing, and boost immune function and reproductive health. Clearly, these are all important bodily functions, which is why consuming foods containing zinc on a daily basis is vital.

Most national health organizations list 40mg of zinc as the upper limit for daily consumption [4], so it is key to understand the amount of zinc that is in your vitamins vs. how much zinc you consume through your diet.

Foods That Contain Zinc

There are a lot of foods containing zinc that you can choose from if you feel you need to boost your daily zinc consumption without worrying about a zinc overdose. Some of the most popular foods that contain zinc [5] include:

  • Meat
  • Legumes
  • Shellfish


All meat is a great source of zinc, but certain red meats such as ground beef are excellent sources. One serving of ground beef contains 44% of the Daily Value [6]. In addition, meat is also an excellent source of protein, iron, Vitamin B, and fats.


Vegetarians or those attempting to lower their meat consumption can turn to legumes such as beans, lentils, and chickpeas for zinc. Legumes are some of the best non-animal foods containing zinc as 100 grams of cooked lentils offers 12% of your daily zinc intake [7]. They are also high in fiber and protein and are an easy add-on to daily meals.


Seafood fans can feel good about consuming shellfish on a regular basis given six medium oysters offer as much as 291% of the recommended daily value. Alaskan crab is another great source of zinc offering about 69% of the daily value of zinc per 100 grams [8].

While these are some of the most popular foods containing zinc, there are many other foods that offer some zinc value including seeds, nuts, eggs, dairy, whole grains, some vegetables, and dark chocolate.

Zinc Overdose Signs

An abundance of zinc in your daily diet while consuming a zinc supplement can present a health risk to your body. It is not advisable to take a large zinc supplement if you regularly consume foods containing zinc. There are two types of zinc toxicity: acute and chronic. Acute toxicity often leads to GI issues like nausea, vomiting and stomach pain whereas people experiencing chronic toxicity show symptoms like anemia and neurological issues. Both zinc overdoses should be avoided and treated promptly by removing zinc from your diet if you suspect a zinc overdose.

If you are curious as to how much zinc causes copper deficiency and results in a zinc overdose, you may be surprised to learn it's not too far outside of the upper limit of zinc consumption. As little as 50mg per day (just 10mg over the 40mg upper limit), is all it takes for a copper deficiency to develop. Therefore, it is very easy to put yourself at risk for a zinc overdose.

Some common zinc overdose symptoms [3] include:

  1. Nausea
  2. Stomach Pain
  3. Fever & Chills
  4. Hypogeusia


Nausea is a common side effect when potent zinc supplements are consumed in excess to treat a cold or in some cases, COVID-19. In most cases, vomiting occurred quickly after zinc supplements were consumed as the body immediately rejected the high concentration in the bloodstream [9. While vomiting is more likely to occur at high doses, it also occurred in a case study that looked at adults who were administered a smaller dose of 150 mg daily for a sustained period of time [10]. Unfortunately, while vomiting can reduce the amount of toxic zinc in your bloodstream, it does not remove enough to prevent the development of copper deficiency.

Stomach Pain

Stomach pain is a comorbid symptom of zinc overdose that often occurs with nausea, vomiting, and diarrhea. In addition, a small amount of GI bleeding and gut irritation is also frequently reported in a large case study review based on the long-term effects of zinc supplements in treating colds [11]. When zinc is consumed in large amounts greater than 20% of the upper limit, the GI tract suffers extensive damage [12].

Fever & Chills

When your body is experiencing high zinc levels, it may respond via a fever and/or chills as it attempts to regulate zinc levels in your body.

Fevers and chills can also develop from other mineral toxicities, therefore you should see a doctor to investigate these symptoms. Your appointment will likely include a detailed discussion of your dietary and medical history along with bloodwork.


Ironically, given its current trending status as a COVID preventative, zinc can actually result in a dysfunction in your tasting abilities. Formally referred to as hypogeusia, the condition occurs due to the presence of a bad or metallic aftertaste in your mouth. This is commonly found in those who use zinc lozenges but can also occur in those who take large doses of zinc over 40mg daily [11]. Oral supplements taken in liquid or lozenge form are most often the cause of this zinc overdose symptom.

Copper Deficiency

Outside of the troublesome zinc overdose symptoms, the main problem with consuming too much zinc is the development of copper deficiency. While only 10mg of zinc is required each day based on the daily value nutritional chart, most doctors prescribe zinc supplements in doses of 135mg per day [13]. This is likely one reason why zinc overdose and copper deficiency are common problems in the medical community.

The primary issue with zinc overdose is that it prevents the body from properly absorbing copper, which then results in a copper deficiency. Neurological problems can develop along with issues associated with chronic anemia.

For this reason, while short-term zinc supplementation is advisable for those who suspect they are not consuming enough zinc or are medically found to be deficient, long-term use of zinc supplements must be carefully monitored and large doses should be avoided [13].

In a study that looked directly at zinc-induced copper deficiency, 13 patients were found to develop troubling zinc overdose symptoms including neuropathy, neutropenia, anemia, paraesthesia, and leg nerve pain. One main issue in the study is that while patients undergoing treatment for zinc deficiency had their zinc levels monitored, most did not have their copper levels checked. Therefore, the potential for patients to have a copper imbalance before therapeutic treatment could have heightened the symptoms of accidental zinc overdose.

The body needs copper to absorb iron, therefore a copper deficiency can lead to an iron deficiency. Iron deficiencies are dangerous as they prevent the body from oxidizing, leaving you feeling weak. Frequent sickness, as well as low white blood counts, are frequently reported when zinc-induced copper deficiency is present. Finally, chronic copper deficiency can actually weaken your body's immune system which negates the purpose of taking iron supplements for many [14].

In the end, in the attempt to treat one mineral deficiency, prescribing doctors actually ended up creating another mineral imbalance with the potential to cause a larger issue than what the patient presented with. This points to the need for both patients and doctors to play a large role in their own health care by properly advocating for one's needs while properly acknowledging the potential side effect of improper zinc supplementation.

Take a Safe Zinc Supplement

As these studies and case reviews clearly illustrate, the safest way to approach zinc supplementation is with a low dose designed to supplement a healthy diet of foods containing zinc. This helps reduce the risk of suffering from a zinc overdose and lowers the risk of developing a copper deficiency.

Immune Super Boost contains 20 mg of zinc along with helpful natural ingredients such as elderberry extract and echinacea that help your body build a strong immune system.† Healthycell's gel liquid vitamin for adults contains nutrients that have been shown to slow viral replication and help support your body's ability to protect against infection.† With advanced MICROGEL technology, absorption is improved by providing small, soluble, nutrient particles that are absorbed in the digestive tract, making this type of supplementation more effective than pills.

If you prefer to take a multivitamin that also supports your body's zinc needs, the Bioactive Multi and Vegan Essentials are excellent multivitamin options with 11 mg of zinc each. Before beginning any zinc supplement it is important to consult with your doctor and disclose all supplements to ensure that you are not at risk for copper deficiency.

Shop Immune Super Boost

Immune Super Boost

†This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

You May Also Like:

How to Determine Your Nutrient Deficiencies

9 Tips to Strengthen Your Immune System

Dr. Giampapa is a world-renowned medical doctor, inventor, and surgeon specializing in anti-aging medicine. He recently received a nomination for the Nobel Prize for his groundbreaking stem cell research, as well as the Edison Award for the Healthycell nutritional supplement for cell health. He was also awarded the A4M Science & Technology award for his development of the BioMarker Matrix Profile – the first computer program to measure aging. Learn more about Dr. Vincent Giampapa.



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