I’d been studying for a doctorate in psychology for four years before I had any idea that nutritional deficiencies could cause mental health symptoms.

I wasn’t enlightened by a lecture or a clinical supervisor but from casually flipping through my cousin’s undergraduate U.S. History textbook late one evening during her Christmas break.

In a section on the American South, there was a description of Pellegra which I learned was a devastating disease that afflicted Southerners for decades in the early part of the 20th century. This disease led to more than 200,000 people being committed to mental institutions because of severe paranoia, dementia and hallucinations (among other physical symptoms).

Only when doctors realized that Pellagra was caused by a simple Niacin (vitamin B3) deficiency could they help…a few months of Niacin supplements and life-long mental health disabilities vanished.  

Further investigation led to the discovery that Pellagra occurred mostly in poor communities which had begun to subsist largely on cornmeal. You guessed it–a staple low in Niacin.

A Case of Scurvy

I was pretty stunned to learn about Pellegra, but that led me to dig further into diseases of the past.

I had heard of Scurvy but hadn’t really connected it to mental health symptoms.

Scurvy is a disease associated with severe vitamin C deficiency that was commonly seen in sailors and was reported as early as the 15th century. Because humans can’t make vitamin C, and these sailors did not have access to perishable citrus fruit on their long journeys, they often developed symptoms of Scurvy, including fatigue, weakness, anemia, and immune dysfunction.

But there are numerous cases in the literature in which mental health symptoms, including depression and even delusions, are seen in association with Scurvy

The amazing thing is that even the most severe symptoms of Scurvy can start to improve within a week of beginning vitamin C supplements.

Our Modern Diet

While we have made gains in many areas in our society, our diet isn’t one of them.

Access to food is still a problem in many places. In fact, there were 17.5 million households in America that were “food insecure” in 2013. This means millions of people go hungry every night, many of them children.

While some are hungry, most of are filled to the brim, overfed and undernourished.

The Standard American Diet most of us consume is filled with chemicalized artificial junk food that’s laden with sugar, hormones, and pesticides, and is very low on nutrient-dense foods like fruits, veggies, good quality fats and pastured meats.

Suffice it to say that the food we eat is playing a huge role in our modern maladies including diabetes and heart disease, as well as in our mental health epidemic.

Here are some recent statistics from the National Cancer Institute on the status of the American Diet:  

-3 out of 4 Americans don’t eat a single piece of fruit a day

-Nearly 9 out of 10 do not consume the minimum recommended daily intake of vegetables

-96 percent don’t eat 3 or more servings of greens or beans in a given week

-99 percent don’t eat the recommended 4 ounces of whole grains a day.

The researchers of the study conclude:

“Nearly the entire U.S. population consumes a diet that is not on par with recommendations. These findings add another piece to the  rather disturbing picture that is emerging of a nation’s diet in crisis.”

 What are We Eating?

1 in 4 Americans is eating fast food every day

Americans consume 31 percent more packaged food than fresh food

Over 10 billion donuts are consumed in the US every year 

There is much to say about the American diet, but for this article it’s enough to know that the food most of us eat lacks the essential vitamins, minerals and good quality fats needed to fuel the basic functioning of the body and brain.

And using Pellagra and Scurvy as examples, we should be crystal clear that simple vitamin deficiencies can wreak havoc on our mental health.

But, the sad truth is that most doctors and mental health professionals are virtually unaware of this connection.

Nutrient deficiencies that can dramatically affect mental health

1) Amino Acids

Amino Acids are vital protein fragments available as “building blocks of the body” after digestion. They are used to build and repair our tissues and become our enzymes, hormones, bones, muscles, and blood.   

They are also the “raw material” for the mood stabilizing and “happy chemicals of the brain” known as neurotransmitters, which include serotonin, dopamine, GABA, and endorphins.

For a short description of symptoms related to low levels of each of these “mood engines,” check out this summary from the excellent book The Mood Cure by Julia Ross.

Low levels of amino acids lead to low levels of neurotransmitters. It’s that simple!

Without the right ingredients it’s impossible to make the soup.

The main reason for amino acid deficiencies is either low protein consumption, poor digestion, or the use of antacid medication, as protein requires adequate stomach acid to be broken down into the amino acids. 

To learn more about the power of the amazing aminos, check out this blog.


2) Zinc

Zinc has been hailed as “the new antidepressant”.

Zinc levels are often shown to be low in both anxious and depressed people. 

Research has shown zinc supplementation can lessen depression and anxiety symptoms. 

The reason for this is at least three-fold.

Zinc is an essential cofactor in conversion of amino acids into two of the most important neurotransmitters of mood (L-Tryptophan into serotonin and L-Tyrosine into dopamine).

The second reason is that zinc helps to regulate copper, which is an essential cofactor for dopamine production. At high levels, copper can cause many mental health symptoms including depression, anxiety, panic disorder and agitation. 

Thirdly, adequate zinc is needed to make digestive enzymes and Hydrochloric Acid which is necessary for protein digestion. 

So low levels of zinc lead to low levels of amino acids and as a result low levels of important neurotransmitters serotonin, dopamine and GABA.

For these reasons, zinc is an important supplement for almost everyone with mental health issues.

The one caveat is that before taking zinc in doses above 30mg, you should have your serum copper levels checked. High doses of zinc can increase anxiety in people with high copper because zinc can cause copper to dump too quickly into the bloodstream (for people with high copper levels, zinc needs to be increased slowly).

3) Vitamin B12

Vitamin B12 is an essential vitamin that has far-reaching effects on the body and is crucial for brain functioning.

B12 supports myelin (which is involved with nerve conduction) and is a necessary cofactor in the methylation cycle (how neurotransmitters are made).

Low B12 can cause cognitive and mental health symptoms including dementia, multiple sclerosis, and psychiatric symptoms including depression, anxiety, fatigue and even psychosis.

There are cases in the literature documenting the ability of vitamin B12 to reverse severe psychiatric symptoms, including psychosis. 

And unbelievably, 40 percent of the general population is B12 deficient. B12 deficiency is even greater among the elderly, but few mental health patients are tested for it.  

Treatment is hampered by the fact that even when B12 levels are checked (which is rare,) many forward thinking practitioners believe that the current laboratory ranges are outdated. Standard labs report B12 as “normal” (measured in the blood) for values above 200 pg/ml. Unfortunately, psychiatric symptoms have been seen in people with blood levels in the 300-400 range

Many functional medicine practitioners believe that optimal levels should be considered to be above 600 pg/ml

Urine methylmalonic acid has been shown to be a more accurate measure for B12 deficiency. This is a marker typically found on the Organic Acid Test.

4) Vitamin B6

Vitamin B6 is one of the most important vitamins for overall mental health because of its role as a cofactor in the production of the neurotransmitters- serotonin, GABA and dopamine.

A deficiency can lead to a wide variety  of mental health symptoms including anxiety, depression, irritability, confusion, fatigue, and worsening of PMS symptoms.

Low B6 is also associated with depression, anxiety and panic attacks.

Common causes of low B6 include the use of oral contraceptives excessive alcohol use, and pyrrole disorder (people who suffer from pyrrole disorder produce excessive levels of kryptopyrrole which bind to zinc and B6, both of which are essential for mental health). For more information on pyrrole disorder check out this link.

On routine blood work, low levels of the liver enzymes  ALT and AST are good functional markers for a B6 deficiency.

5) Omega 3 Fatty Acids

Omega 3 fatty acids (EPA and DHA) are well-recognized for their ability to help heal mental health symptoms.

There are at least four double-blind placebo controlled trials for depression and five trials for schizophrenia that report therapeutic benefit of omega 3 supplementation. 

Evidence also abounds for the use of omega 3 in mitigating depressive symptoms in patients with bipolar disorder. 

Regarding anxiety, research shows that people experiencing the most anxiety tend to have the lowest levels of omega 3 fatty acids in their bodies.

Because the human body cannot produce omega 3s and the standard American diet is high in inflammatory omega 6 oils and low in omega 3 oils, many people are low in omega 3s.  

Most people need to make a concerted effort to get enough of the mood supportive oils. These oils are found mostly in cold water fish which many people tend to avoid because of real fears around mercury

Because of this, it may be best to supplement with fish oil or krill oil supplements. When buying fish oil supplements, look for the key words “molecularly distilled” and buy reputable brands, because purity is important. Two good-quality commercially available brands are Carlson’s and Nordic Naturals.

6) Lithium

When most people hear the word Lithium, they think about the pharmaceutical “drug” used by psychiatrists to treat bipolar disorder. But what most people don’t know is that this powerful psychiatric drug is actually a mineral found in nature.

You can find it on the “Periodic Table” (remember from high school chemistry class), and it was also included as a main ingredient in the soda 7up, which was originally called “Bib-Label Lithiated Lemon-Lime Soda.”  This drink actually contained Lithium until 1948.)

So at high doses it’s used by psychiatrists as an the most effective agent to treat mood instability, but it has been used for decades at very low doses (as low 2.5 milligrams) for a wide variety of conditions including ADHD, agitation, aggressiveness, Bipolar disorder, alcohol abuse and others

According to Dr. James Greenblatt, an integrative psychiatrist who has used low-dose lithium for more than 20 years:

“I believe that lithium is the most effective medication in psychiatry. Psychiatrists over the years have been hesitant to prescribe lithium because it is toxic at pharmaceutical doses. Concerns about side effects and toxicity are nonexistent when lithium is used as a nutritional, low-dose supplement. The untapped potential of low-dose lithium in psychiatry has implications for dramatically changing clinical practice with a safe, integrative strategy for the treatment of mental illness.”

Check out this link for a number of cases where low dose lithium was very successful in helping mental health symptoms. 

One amazing study used data from 27 Texas counties showing that the incidence of suicide, homicide, and rape were significantly higher in counties whose drinking water contained the lowest levels of lithium.

Low-dose lithium has also shown to have promise in the treatment of Alzheimer’s disease. It seems to protect the brain from developing the plaques and tangles associated with Alzheimer’s as well as promoting repair to existing plaque.

A recent article summarizing the benefits of low-dose lithium described four randomized clinical trials showing low-dose lithium yielded more benefit than placebo. In five of seven cases, low-dose lithium worked as well as standard-dose lithium for patients with dementia.

Based on his review the lead author stated, “Lithium is, by far, the most proven drug to keep neurons alive, in animals and in humans, consistently and with many replicated studies.”

Lithium levels can easily and accurately be measured in a simple Hair Mineral Analysis Test to determine the need for supplementation. 


7) Cholesterol

Low cholesterol is a major factor in mental health.

You heard me right, LOW cholesterol. The funny thing is that almost no medical or mental health practitioners know anything about this.

In referring to low cholesterol I mean total cholesterol below 160 on standard blood lab tests you get from your doctor on your yearly physical. Just the basic cholesterol test (but remember to look at the “total cholesterol” number).

One excellent large-scale study in the Journal of Psychiatric Research found that men with low total cholesterol were 7 times more likely to die prematurely from causes such as suicide and accidents. 

Low Cholesterol is linked to anxiety and depression in women as well as men.

One major reason for the epidemic of low cholesterol (and corresponding mental health symptoms) is the use of Statins which are drugs that effectively lower cholesterol. Since most medical providers do not pay attention to low cholesterol, it’s not uncommon for people to have total cholesterol driven far below the 160 danger range. 

Cholesterol can be raised by introducing foods into the diet that are high in this dietary substance (e.g. eggs). There is also at least one supplement company that actually carries cholesterol supplements.

One of the first things I do when I see a new patient to is to ask for bloodwork. Frequently, I see total cholesterol in the 120-130 range in patients exhibiting mental health symptoms. Children with Autism frequently have total cholesterol below 100. 

Where to go from here

Clearly there are other nutrients (magnesium, iron, vitamin D and others) worth mentioning in connection to mental health symptoms.

I wrote this article to help make clear how important adequate nutrition is to mental health and how deficiencies of specific nutrients can lead to mental health symptom.

So, begin to educate yourself about how important the right diet is for your mental health.

Here’s a link to my website where download a FREE ebook I wrote on the connection between diet and mental health.

The most important part of a mentally healing diet is that it focuses on REAL or whole foods, because only real foods have the vitamins, minerals and amino acids that your body and brain need to promote mental health.


Also, even without testing, there are a number of supplements you can start to take for your mental health.

These include:

-30mg of Zinc (I prefer to use the most absorbable form, Zinc Picolinate) which is best tolerated with dinner.

-100-200 mg of vitamin B6

-2000 mg of well-sourced Fish Oil

-For amino acids, many people are able to find the right ones to take such as tryptophan, GABA, or tyrosine (and the right doses) based on symptoms, by following guidelines laid out in the excellent books The Mood Cure.

For the other nutrients listed here, you probably should be tested for deficiencies before starting them. Best to work with a functional medicine practitioner knowledgeable about mental health. Here’s a link to find medical practitioners skilled in this area.

I also offer phone consults to help identify nutritional deficiencies that are blocking mental health recovery. To find out more check out my website.


Books to learn more about the connection between nutrient deficiencies and mental health:

The Mood Cure, by Julia Ross, MA

Anti-Anxiety Food Solution, by, Trudy Scott, CN

NutrientPower, by Dr. William Walsh, PhD

Please feel free to ask questions or share any thoughts in the comments section below. I’d love to hear from you!


In good (mental) health,


Dr. Josh


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