Nutrition and Depression: What’s the Link?

Have you ever had a craving for sweets when you were sad or binge-eaten processed and salty foods when under a lot of stress? Most of us have – which means we intuitively understand that food and mood are connected. What you may not know is that poor nutrition can play a role in the development of depression.

Although it was once considered to be on the outskirts of psychology, the field of nutritional psychiatry is slowly making its way into the mainstream. Nutritional psychiatry (or nutritional psychology) studies how nutrition and diet affect mental health. With growing evidence, the idea that what we eat affects our mental health can no longer be denied.

Could nutritional deficiencies be contributing to depression symptoms in your life? Read on to learn more about how holistic mental health treatment can help.

The link between nutrition and mental health

What we eat and how we feel are inextricably linked. We generally understand this when it comes to our physical health; for example, if you catch a cold or have stomach trouble, you might think automatically about what your diet’s been like lately and what you might have eaten (or not eaten enough of) that could have contributed to poor health.

We don’t tend to automatically associate our mental health with nutrition and food, even though research tells us that what we eat can significantly influence how we feel emotionally. This is sometimes called the “food-mood connection.”

This connection between food and mental health can be explained in many ways^[1].

First, our mental health and emotions result from what’s happening in our brains. Diet can influence levels of neurotransmitters, which are chemical messengers in the brain that regulate mood and emotions.

When we eat certain foods, our bodies use the nutrients from those foods to produce neurotransmitters. For example, foods rich in amino acids, like turkey and bananas, help create serotonin, a neurotransmitter that boosts mood.

Eating a balanced diet filled with essential nutrients supports the production of these neurotransmitters, boosting your mental health. On the other hand, an unhealthy diet may lead to imbalances in neurotransmitters and can contribute to feelings of sadness or anxiety.

Your gut also plays a role here. The gut – specifically, the enteric nervous system, which regulates the gut – is often called the “second brain.” This is because the gut produces many of the same neurotransmitters that are released in the brain. A diet that supports a diverse and healthy gut microbiome, with prebiotic and probiotic-rich foods, may contribute to improved mental health.

On top of how certain foods and nutrients affect the brain and the gut, eating nourishing meals is also a basic self-care practice. When you forgo this, your overall health suffers – including your mental health. Plus, if eating a poor diet makes physical health symptoms (like chronic pain) worse, this can make you feel worse mentally as well.

The impact of diet on depression

Depression, specifically, has been linked in many research studies to diet and nutrition.

In some ways, depression and poor nutrition get locked in a vicious Catch-22. This is called a bi-directional relationship, meaning each makes the other worse. Poor nutrition can lead to depression and vice versa.

People with depression may eat poorly and be less likely to stick to a healthy diet for various reasons. For example, they may be prone to emotional overeating or have a lack of appetite.

Research has found depression and other mood disorders like premenstrual dysphoria can also affect food choices. This is because certain foods – particularly sweets and foods with high-fat content – temporarily improve mood. But these foods also don’t have a lot of nutritional content and can worsen mental health in the long term^[2].

Because of this complex relationship, people may assume poor nutrition does not lead to heightened depression risk, believing their relationship can be explained solely because depressed people are less likely to eat well.

However, some research studies show people who eat poor diets are more likely to develop depression symptoms later on – even when they don’t have any prior history of depression.

For example, one review concluded deficiencies in several different nutrients and minerals can result in depression, and there is strong evidence for a causal relationship. This means there is enough evidence to conclude nutritional deficiencies can cause depressive symptoms in some cases^[3].

Research has also found that improving nutrition can also improve symptoms of depression. In one study, the group who stuck to the Mediterranean diet (including large amounts of vegetables, whole grains, fish, and healthy fats like olive oil) saw a significant improvement in their depression symptoms – while the control group (who didn’t make any changes to their diet) saw no progress at all^[4].

Does this mean that a poor diet will cause depression for every person? No; evidence for a causal relationship doesn’t necessarily mean it’ll happen this way every time. Some people may have nutritional deficiencies and not experience subsequent depression. But what these studies show is a significant link, and poor nutrition could be one of many risk factors involved in depression symptoms.

Eating disorders and depression

Although not related to nutrition specifically, it’s also worth mentioning the significant link between eating disorders and depression. Eating disorders very often appear together with depression; research studies show that around 40% of people who live with eating disorders also live with depression^[5].

There are many explanations for this; one major theory is that other factors (like genetics and early childhood trauma) raise your risk of developing both eating disorders and depression. It’s hard to know which comes first when it comes to eating disorders and depression.

However, malnutrition, obesity, and other health conditions associated with eating disorders could easily contribute to depression in many people. We know some physical health conditions, such as chronic pain, appear almost 100% of the time with depression.

In addition, eating habits themselves could worsen depression. For example, binge-eating disorder is characterized by a period of eating a lot of food very quickly, followed by intense shame and guilt. These feelings of shame could impact self-esteem and worsen depression symptoms.

Key nutrients for managing depression

To manage symptoms of depression, consider eating a well-balanced diet that includes food from a variety of food groups. There is no single food that can prevent or treat depression. But in general, the American diet of highly processed foods may contribute to higher depression, while a Mediterranean diet has been found to lower depression. Try eating lots of:

• Fruits and vegetables
• Whole grains and legumes
• Fish and poultry in moderation
• Healthy fats, especially olive oil
• Eggs

On top of that, some essential nutrients may help you manage depression, especially if you have deficiencies in these areas^[6].

Omega-3 Fatty Acids

Omega-3s are often found in fatty fish, flaxseeds, and walnuts and are essential for brain health, reducing inflammation, and promoting the production of neurotransmitters like serotonin, which regulates mood.

Vitamin D

Often called the “sunshine vitamin,” Vitamin D plays a vital role in mood regulation. Exposure to sunlight and consuming foods like fortified dairy products or fatty fish helps you get enough vitamin D in your system.

Antioxidants

Antioxidants are found in colorful fruits and vegetables and protect the brain from oxidative stress and inflammation, which can contribute to depressive symptoms.

B Vitamins

Essential for neurotransmitter synthesis and supporting mood stability, B vitamins (like B6, B12, and folate) are abundant in whole grains, leafy greens, and legumes.

Magnesium

Magnesium is found in nuts, seeds, and leafy greens. Magnesium helps with nerve function and relaxation, which can potentially reduce symptoms of anxiety and depression.

Tryptophan

Tryptophan is an amino acid found in turkey, bananas, and milk. It is a precursor to serotonin, and helps to improve mood and promotes relaxation.

Zinc

Zinc is one of the most essential nutrients for brain function and neurotransmitter activity. You can find zinc in foods like meat, legumes, and seeds.

Probiotics

Remember, your gut is your second brain. Probiotics benefit the gut-brain axis and can positively influence mood and mental well-being. They’re found in fermented foods like yogurt and kimchi.

Holistic mental health treatment at The Center • A Place of HOPE

At The Center, we understand every aspect of your health is intertwined; it’s impossible to separate your physical and mental health. Nutrition is a core part of your mental health, and you must learn how to care for yourself holistically.

That’s why we use a unique Whole Person Care approach to mental health treatment, focusing on your physical, mental, nutritional, relational, and spiritual health.

If you’d like more information about admissions, you can schedule a callback with us. One of our team members will get back to you at your earliest convenience.

1 – https://www.apa.org/monitor/2023/06/nutrition-for-mental-health-depression
2 – https://pubmed.ncbi.nlm.nih.gov/16545403/
3 – https://journals.sagepub.com/doi/abs/10.1177/1559827607299725
4 – https://www.tandfonline.com/doi/full/10.1080/1028415X.2017.1411320
5 – https://www.nationaleatingdisorders.org/statistics-research-eating-disorders
6 – https://www.medicalnewstoday.com/articles/318428