Nutritional Psychiatry: Using Food to Fight Depression

Nutritional Psychiatry: Using Food to Fight Depression

Our brain is one hardworking part of the body. It never stops functioning, even when we sleep. In order for the brain to work properly 24/7, we need to power it with the correct fuel – and this is where proper nutrition comes in.

Nutritional psychiatry is a developing field studying how nutrition affects our psychological health. It reveals how the food we eat affects our brain functions and, in turn, our overall emotional state. 

It’s a topic of particular interest to our team at Whole Harvest as there seems to be no end of studies being done on the health benefits of a whole food plant-based diet.

Did You Know This About the Role of Diet in Mental Health?

Diet and Mental Health

Nutritional psychology researchers have shown that diet plays a big role when it comes to mental health. According to Dr. Roger Walsh, poor nutrition also contributes to developing symptoms of mental health conditions like anxiety and depression.

However, diets that contain essential vitamins and minerals like vitamin D, several B vitamins, and omega-3 fatty acids can help produce serotonin in the brain and gastrointestinal tract.

Here’s how that helps you.

Serotonin is an important neurotransmitter acting as a “messenger” from the brain to other parts of your body. Because receptors can be found in both the GI tract and the brain, serotonin plays a major role in the gut-brain connection and appears to play a role in emotional processing 

Good gut-brain health is nurtured by healthy eating because the good bacteria in our gut microbiome serve as a guard to prevent cognitive impairments.

On the other hand, with improper diets, such as consuming excessive sugar, the gut microbiota sends signals to our brain that can trigger symptoms of mental health disorders.

If you’re like us, this connection comes as a huge revelation. We all know instinctively that eating poorly has an effect on our sense of well-being, but having evidence and a way to name what’s really going on is a game-changer!

More importantly, it means we can do something about it!

Discover the Benefits of Adopting a Nutritional Psychiatry Approach

A 1998 article by Dr. Joseph Hibbeln mentions that as early as the late 1990s, scientists had already noticed a link between countries where people eat fish and lower rates of depression cases. Even then, they recognized that a nutritional psychiatry approach can be advantageous for an individual’s mental health.

How? Proper food choices help to:

  • Support brain chemistry without undergoing invasive treatment

  • Regulate our mood with steady blood sugar levels, improving cognitive performance

  • Provide the body with necessary nutrients for physical and mental growth with minimal to zero side effects

With these benefits, a diet checklist should include foods that decrease the chance of developing depression symptoms. A healthy diet feeds the good bacteria in the gastrointestinal tract, thereby promoting a healthy gut biome.

Supporting article, how to build healthy eating habits that last.

We’ll look at what constitutes a healthy diet in a bit, but first let’s make sure you’re able to properly recognize the signs of depression.

Understanding the Symptoms of Depression

With the onset of depression, individuals may start displaying various signs and symptoms. 

Common signs and symptoms

An individual may be experiencing depression if they have any of the following signs and behavioral changes:
  • Hopelessness and pessimism
  • A tendency to become angry, irritated, and frustrated
  • Consistent “empty” feeling
  • Loss of interest and joy in doing previously enjoyable activities
  • Isolation from social groups
  • Difficulty in making decisions, focusing, and remembering information
  • Suicidal thoughts and tendencies
Individuals may also experience physical changes and symptoms like:
  • Sleep-related concerns
  • Slowed-down movements and fatigue
  • Increased drug and alcohol intake
  • Persistent aches, pains, cramps, or gut issues despite treatment
  • Fluctuations in weight
  • Decreased sexual desire and performance

These changes must occur nearly every day over a minimum of a two-week span before depression can be diagnosed. The severity varies among individuals as well as the duration, with some people experiencing these symptoms for many months. 

Be Aware of These Risk Factors for Developing Depression


Aside from genetic and environmental factors, our food intake also increases the likelihood of developing depression.
  • Excessive sugar
Since sugar affects our blood sugar and energy levels, it can contribute to developments of mood disorders and mental illnesses.
  • Diets that lack nutrient supply
Processed foods and junk foods contains artificial chemicals and refined ingredients (empty calories). This deprives the brain of the nutrients it needs to work properly.
  • Insufficient omega-3 fatty acids

Omega-3s serve as neuroprotectants that help stabilize mood and enhance the effect of traditional antidepressants. People who lack this are more vulnerable to experiencing emotional imbalance than those who consume fish and fish oil sources regularly. 

On the other hand, a healthy diet can decrease depression symptoms. In a 2017 study, researchers found that clinically diagnosed depressed individuals who were given foods rich in nutrients like green leafy vegetables and fresh fruits had significantly reduced depression symptoms compared to those who didn’t receive any changes to their diet.

What we eat matters more than we can possibly know!

Diagnostic criteria for major depressive disorder (MDD)

So, how do mental health experts diagnose a depressive disorder? When following the diagnostic criteria for major depressive disorder (MDD), mental health professionals look at an outline of specific symptoms and their duration before making a diagnosis.

As outlined in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), these diagnostic criteria help in accurately identifying MDD and differentiating it from other brain diseases.

One of the main criteria for major depression includes a depressed mood observed by the individual or people close to them and a loss of interest in doing daily activities. Other symptoms are:

  • Significant decrease and increase in appetite
  • Lack of sleep or oversleeping
  • Fatigue or loss of energy
  • Feeling guilty and worthlessness
  • Loss of ability to concentrate and make decisions
  • Recurrent suicidal thoughts
  • Poor personal hygiene

Effects from existing medical conditions and drug and alcohol consumption are excluded from the assessment.

It goes without saying that if you feel any of these symptoms, you should seek professional guidance and diagnosis.

The Role of Diet in Mental Health and Depression

OK, now that we see the signs of depression clearly, let’s get back to the big question.

How does a poor diet affect our mental health, and how does nutritious food boost our ability to regulate moods?

Let’s understand the impact of poor diet on mental health

Vitamin D

Vitamin deficiencies can also affect an individual’s psychological state. When the brain does not receive the specific nourishment it needs, our cognition and mental functioning become impaired.
  • Vitamins B6, B9, and B12 deficiency
Insufficient B vitamins may result in decreased serotonin levels leading to mood and anxiety disorders.
  • Low levels of vitamin D

Vitamin D receptors can be found in several parts of the brain, which are responsible for controlling behavior and emotions. Low levels of this vitamin can cause brain health problems.

This is supported by a 2019 meta-analysis where vitamin D supplements are given to patients clinically diagnosed with major depression resulting in reduced symptoms and improved depression ratings.

You should know about these dietary interventions for people with depression.

Now that we know how a poor diet affects our brain health, how do we take preventative measures? How can we take back control of our health?

According to a study by Food Tank, processed and refined foods, which make up over 73% of the US diet, worsen depression symptoms and other mental concerns.

In contrast, he further discussed that whole foods, including fruits and vegetables, support the digestive process to maintain proper gut health. 

Here are some more well-researched dietary interventions for individuals with depression:

Whole Food Plant-Based Diet

This way of eating is composed of mostly plant-based foods like fruits, green vegetables, legumes, nuts, seeds, and whole grains.

A plant-based diet similar to the blue-zone diet is low in animal protein with moderate amounts of fish, poultry, and dairy, but its focus on abundant fresh, whole foods rich in antioxidants, fibers, and omega-3 fatty acids makes it ideal for people clinically diagnosed with depression.

Probiotic supplementation 

Probiotic consumption is vital for improving gut health. It greatly influences our mood and prevents mental health disorders. Sources include yogurt, kombucha, sauerkraut, cheese, miso, kimchi, and fermented milk.  

Antioxidant-rich diet

Oxidative stress damages the brain and results in nervous system impairment. Studies show that antioxidant foods counteract the negative effects of oxidative stress and aid in proper cognitive functioning. Antioxidant-rich diets include apples, avocados, berries, mushrooms, broccoli, spinach, cabbage, asparagus, kale, and other similar leafy greens.

These foods are rich in nutrients and are important for brain health and mood regulation!

Aside from the nutritious food sources listed above, there are other dietary sources that contribute to healthy brain functioning and mood regulation. In a 2015 review, scientific evidence shows omega-3 fatty acids lower the risk of developing mental illnesses like depression.

Why? They contain high levels of EPA and DHA that hamper the release of pro-inflammatory chemicals linked with depression and bipolar forms of this condition.

Omega 3

Omega-3s can be found in eggs, oily fish, and plant sources like flaxseed oils, chia seeds, and brussels sprouts.

Nutrients like antioxidants and flavonoids that improve cognitive abilities can also be found in dark chocolate and green tea, while plain yogurts give probiotics essential for gut health and mood regulation. Although beneficial for your mental health, these food sources should only be consumed in moderation.

These dietary strategies can help manage the symptoms of depression.

Introducing food and nutrients that nurture mental well-being helps manage the symptoms of depression. Let’s take a quick look at some dietary strategies you can incorporate into your daily life.

Drinking Water

  • Drink enough water
Proper nutrition involves drinking enough water. Dehydration can cause changes in our emotions and limit our bodies’ capacity to absorb necessary nutrients.
  • Include complex carbohydrates
Eating complex carbs such as brown rice, oats, and beans instead of refined carbs like white sugar and bread helps to keep blood sugar levels steady, regulate mood, and normalize energy levels.
  • Consume protein-rich food regularly
A healthy diet also includes lean protein at every meal that can be sourced from eggs, poultry, seeds, fish, and some green vegetables like spinach. It’s an essential macro that contains tryptophan which helps with depression when taken adequately.
  • Not skipping meals

Regular eating, including healthy snacks between meals, fuels the brain. By improving the quality and quantity of the food we consume instead of eliminating an entire lunch or dinner, we can ensure we have steady energy levels throughout the day.

The amazing link between nutrition, mental illness, and the vagus nerve

The vagus nerve sounds like something out of a science fiction flick, but it’s very real - and hugely important.

The vagus nerve is a “communication line” between the gut and the brain.

So, make sure your vagus nerve is sending happy messages back and forth!

Consuming a well-balanced diet balances the bacteria found in the gut which, via this connective nerve, plays a role in how you feel and behave.

On the other hand, vitamin deficiencies and disease-specific diets may increase the chance of chronic inflammation and developing mental health disorders. When given nutritional supplements, scientists point out that clinically diagnosed individuals show signs of improved depression ratings and reduced symptoms.

Bottom line: there is a massive, constant, critical connection between the food we eat and our mental health!

Follow a Healthy Diet to Fight Depression. You Can Do It!

In a nutshell, what we put on our plate affects how we fuel our brains, and ultimately, how we feel.

Incorporating depression-fighting foods into our grocery list and daily diet boosts our mental and emotional health.

When we embrace a healthy diet that’s nutrient-dense, we support the complex gut-brain connection and provide nourishment for both our bodies and brains. Always remember that small positive changes in our nutrition can have big effects on how we feel and how we behave. You might be surprised that the first proactive step towards a healthier mind might just be a grocery run away.

How to Follow a Healthy Diet in a Busy World

Whole Harvest Meal Delivery

If you’re like us, what’s frustrating about reading an article like this is that you get it. You see the value of a healthy diet but don’t know what to do about it.

We have yet to meet someone who doesn’t want to eat healthy, but the time it takes to shop for healthy ingredients, prep meals, and learn how to prepare them stops far too many well-intended people in their tracks.

A whole food plant-based diet focuses all of your energy on nutrient-dense, healthy food, but learning to prepare food this way can be daunting.

There’s a good reason why so many people are turning to meal delivery services for the boost they need to get healthy. Often, it’s the only solution for busy people.

Whole Harvest was created for the sole purpose of helping you take back control of your health. With delicious, ready-to-eat entrées and snacks delivered fresh to your front door, you are out of excuses!

More importantly, you’re empowered to do the best thing possible for your health! We also use an industry-leading vacuum sealing technology which keeps your food fresh longer and gives you more flexibility in how you use your meals.

  • Keep them foremergency meals” when you’re out of time to cook.
  • Take them to work to make it easier to eat healthier on the go.
  • You can even replace every lunch and dinner throughout the week, saving TONS of time in shopping, chopping, and cooking your own meals.

Whole Harvest is 100% committed to whole food plant-based, oil-free, delicious, pure food! We are leading the industry in our commitment to purity and freshness all while offering our meals at affordable prices.

We’re happy to say you’re now out of excuses to do the best thing for yourself. Visit Whole Harvest now and build your first custom delivery box of delicious, innovative, healthy meals!

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