Zinc and Depression: What's the Connection?

Not getting enough of the trace mineral zinc may play an important role in depression in some people. Zinc is found in oysters, meats, nuts, dairy products, and some other foods.

Emerging evidence suggests that some people with depression may do better if they receive temporary zinc supplements along with taking antidepressants or getting other types of therapy. 

This article discusses the potential role of zinc in depression, causes of low zinc levels, how to get enough zinc through food or supplements, and related topics.

What Is Zinc?

Zinc is one of the micronutrients that your body needs for optimal health. The word “micronutrient” refers to substances your body needs to live but only in small amounts. You might also hear zinc called a “trace element.”

Zinc is an important part of hundreds of different proteins in your body. So if you don’t have enough zinc, these proteins may not work optimally. 

Some of these proteins play important roles in brain and nervous system performance. For example, some regulate certain neurotransmitters—important signaling molecules found in your brain and nervous system. 

How Might Zinc Play a Role in Depression?

Scientists are still learning about how having low zinc in your body may affect depression—which is the case in some people.

It is known that zinc plays an important role in toning down excess inflammation in the body (part of your immune system's response to injury and illness). It is also believed that excess inflammation may worsen depression in some people. So, zinc and depression might be related. 

Several studies have shown that people with depression tend to have lower amounts of zinc in their blood compared to people who aren’t depressed. Moreover, people who have the lowest zinc levels tend to have more severe forms of depression.

Stress may also lead to lower amounts of zinc and other micronutrients in the body. Long-term stress may also increase one’s risk of getting depression. So, some of the same underlying factors causing your depression might also be causing low zinc levels, which might make your depression worse. 

Scientific Studies of Zinc in Depression

Various scientific studies have looked at whether supplementation with zinc might help some people with depression, and the results have been mixed.

A 2021 meta-analysis (an analysis based on statistics gathered from multiple scientific studies) looked at data from five different studies in people with depression. On the whole, it didn’t find a major improvement in terms of the impact of zinc when taken by itself. 

However, people who were given zinc along with an antidepressant medication (such as Prozac, a brand of fluoxetine) tended to improve more than people who received only an antidepressant.

A couple of studies in this meta-analysis looked at supplementing with zinc in people who hadn't had a good response to antidepressant medications in the past. When zinc was added to antidepressant treatment, those people tended to experience better symptom relief.

What Foods Are High in Zinc?

Most people in the United States get most of their zinc through red meat and poultry. Oysters contain more zinc per serving than any other food. Some other good sources of zinc include:

• Some seafood (like crab)
• Food fortified with zinc, like breakfast cereal
• Whole grains
• Cheese, milk, and yogurt
• Nuts (like cashews or almonds) 
• Beans

Zinc from animal products tends to be better absorbed by the body than zinc from plants. 

Zinc is also available as a supplement on its own and as part of many multivitamins. 

What Causes Low Zinc Levels?

Zinc deficiency happens when you don’t get enough zinc in your diet or your body can’t absorb it well enough. It is thought to be one of the most common kinds of nutrient deficiencies worldwide.

People who just aren’t eating enough food generally, or who are not eating an adequate variety of foods, may not have enough zinc.

The following conditions may also increase the risk of zinc deficiency:

• Diseases that affect the absorption of foods (like celiac disease or inflammatory bowel disease)
• Alcohol use disorder
• Chronic liver disease
• Chronic kidney disease
• Diabetes
• Cancer

People who are pregnant or breastfeeding may also have an increased risk of not getting enough zinc. Older adults also are prone to zinc deficiency.

Because zinc from animal products tends to be better absorbed than zinc from plants, vegetarians may have an increased risk of zinc deficiency. Also, vegetarians typically eat high levels of beans and whole grains. These foods contain phytates that bind to zinc and prevent its absorption.

Can I Get My Zinc Levels Tested?

People sometimes get blood tests for zinc if a healthcare provider is worried they might be deficient. However, researchers are still working on better tests to check for zinc deficiency.

Tests of zinc levels in the blood don't necessarily give good information about how much zinc you have in your body. A person might have a problem with zinc deficiency, even if their blood tests come back in the normal range. 

Sometimes healthcare providers can diagnose a potential zinc deficiency based on symptoms and risk factors alone.

Do I Need Zinc Supplementation for Depression?

As of now, science is still learning a lot about the role of zinc in depression. Currently, the American Psychiatric Association does not include zinc supplementation as part of its clinical guidelines. 

However, if you have depression and think you might be zinc deficient, don’t hesitate to bring it up with your healthcare provider. Some psychiatrists (medical doctors specializing in mental health diagnosis and treatment) or other healthcare professionals may think it is reasonable to try zinc supplementation for a while.

It might especially be helpful to try zinc supplementation if you have depression but haven’t responded as well as you’d like to medication.

Ideally, you should only take zinc under the guidance of a healthcare provider. They can help make sure you don’t take too much while also monitoring you for potential side effects. They can also make sure that zinc won’t cause any potential problems with other medications you might be taking.

Taking a supplement for zinc may not make sense for you. However, it’s reasonable to look at your diet and see if you might be at risk for deficiency. You may want to increase the number of foods high in zinc that you eat. 

Can I Take Too Much Zinc?

You can take too much zinc. Although it’s important to have enough zinc in your body, too much can also be a problem. This might happen if you take too much at once, or if you take it over too long of a period. Some potential issues could be:

• Belly pain
• Vomiting 
• Diarrhea
• Headache
• Anemia 

Summary

Scientists are still learning about the potential role of zinc in depression. Low zinc levels may play a role in depression in some people, maybe through links to stress and inflammation. Unfortunately, blood tests for zinc don't always reliably show if a person is zinc deficient.

Temporary supplementation with zinc may help some people with depression, especially people who haven’t responded well to antidepressant medications. It's best to work with a healthcare professional to make sure you don't take too much, which could cause its own problems.

A Word From Verywell

If you are someone who has struggled with depression, you may be looking for anything that may help you feel better. It’s reasonable to talk about trying zinc supplementation with your healthcare professional. But don’t go overboard—taking prolonged, excess zinc can cause problems as well.