We realize that there is an intimate connection between what we eat and how we look, but have you ever considered that what we eat also determines how we feel mentally? Sure, eating an ice cream cone on a hot day is going to make us feel happy, or diving into a bowl of our grandmother’s cooking is going to make us feel all warm and fuzzy inside, but what about the long term effects of our diet on our mood? If you are suffering from any type of mood disorder ranging from anxiety and irritability to depression, then there is a good chance that what you’re eating is playing a role.
Few people are aware that there is a connection between nutrition and depression. Depression is more typically thought of as strictly biochemical-based or emotionally rooted condition, but research now shows that nutrition can play a key role in the onset as well as severity and duration of depression. The role of nutrition and mental health is not only about what you are eating, but what you are not eating as well. So that means that if your diet is lacking in the health department, your mood could be at risk.
The good news is that research has pinpointed which nutrients play the largest role in our mood, and which foods have the greatest chance of leading to mood disorders including depression. So if you are feeling depressed, it may have nothing to do with your external circumstances or your genetic biochemical state, but what you are choosing to eat instead. In my book, that’s good news! Changing the diet is easy compared to changing your life situation or your brain patterns; so let’s take a closer look into the nutrition of depression.
How the Foods you Eat Affect how you Feel
Our body and our internal organs need nutrients in order to function properly, and the brain is no exception. We need a steady flow of the right nutrients in order to maintain good physical health, and a good mood. This is because dietary changes can bring about changes in our brain structure (chemically and physiologically), which can lead to altered moods. And why is that? Well, because our moods are developed from chemical messages that are sent from neurotransmitters.
The main neurotransmitters involved in mood are serotonin (wellbeing and happiness chemical) and dopamine (pleasure seeking chemical). Neurotransmitters are made from specific nutrients (amino acids) that we must get from food, which is why eating the right diet is so critical. When we do not have the proper nutrients to make neurotransmitters, or if the neurotransmitters cannot do their job properly, then mental illness or states of depressed moods can occur.
Neurotransmitters can be negatively affected, leading to mood disorders including depression, when they cannot do their job properly. This can happen when inflammation is too high in the body (atypical Cortisol secretion patterns have been linked to depression, stress, and anxiety), when nutrient deficiencies occur, when blood sugar levels are unstable, and when sugar and chemical ingredients are introduced through processed foods.
The main factors that influence mood are as follows:
- Consuming inadequate amounts of specific nutrients
- Blood sugar instability (eating high-glycemic foods, irregular meal schedule and skipping breakfast)
- Inadequate sunshine (vitamin D!) exposure
- Not eating enough healthy complex carbohydrates to make serotonin (you’re feel good brain chemical)
- Consuming the foods that increase the risk for depression
- Poor gut bacteria
Nutritional deficiency or insufficiency
A notable feature of the diets of patients suffering from mental disorders is a deficiency in essential vitamins, minerals, amino acids and omega-3 fatty acids that are precursors to neurotransmitters (the chemicals that make us feel good). Studies have indicated that when these vital nutrients are replaced through supplementation or a diet change than there is a reduction in patients’ symptoms.
Through reviewing the diet of people who suffer from depression, an interesting observation is that their nutrition is far from adequate. They tend to make poor food choices, selecting foods that might actually contribute to depression. Nutrition plays an essential role in brain function, and poor nutrition significantly increases one’s risk for depression.
Here are the following nutrient deficiencies that influence mood:
B-complex vitamins: B-complex vitamins serve as cofactors for the production of neurotransmitters. Inadequate levels of B-vitamins, especially folate, vitamin B12, niacin, vitamin B1, B2 and vitamin B6, can disrupt neurotransmitter synthesis. This not only may lead to mood alterations, but can also impact overall brain function, memory, and cognition.
- Folate: Clinical trials have demonstrated that folic acid both relieves depression on its own and enhances the effect of antidepressants.
- B12: Vitamin B12 should always be measured in the event of depression (or any other psychological problems) as a vitamin B12 deficiency can be a reversible cause of various neuropsychiatric disorders. One should also consider whether a vegetarian diet or malabsorption due to celiac disease or gluten enteropathy is a factor in B12 deficiency.
- B1: In women, baseline vitamin B1 status was linked with poor mood and an improvement in the same after 3 months was associated with improved mood. B1 is known to modulate cognitive performance particularly in the geriatric population.
- B6: Vitamin B6 is a cofactor for the production of most neurotransmitters, but it is particularly important for serotonin synthesis. B6 levels are often low in women taking oral contraceptives and research has shown that B6 supplementation in these women can improve mood. For example, one study showed 22 women whom had depression associated with oral contraceptive use and a B6 deficiency saw significant improvement in their symptoms with B6 supplementation.
Omega-3 fatty acids: Fatty acids are critical components of nerve cell membranes and play an important role in neuronal communication. Fatty acid imbalances can impair the transmission of messages between nerve cells, leading to cognitive deficits and mood alterations, including depression. One investigation showed that adding the omega-3 fatty acid EPA to conventional antidepressant treatment relieved depressive symptoms. Among children with depression, supplementation with omega-3 fatty acids demonstrated “highly significant” effects on symptom scores. In a review article from 2006, researchers analyzed results from six published studies and found that omega-3 fatty acids can reduce symptoms of depression among adults as well. Because they are anti-inflammatory, omega-3 fatty acids also reduce the risk of cardiovascular disease, which is highly associated with depression.
Magnesium: Magnesium is a cofactor for more than 300 enzymes in the body; it is important for blood-sugar regulation, and has a calming effect on the nervous system. Some evidence shows a link between magnesium deficiency and depression, and a recent, comprehensive review in the Journal of Medical Hypotheses suggests that magnesium supplementation is a viable approach for depressive symptoms.
Vitamin D: Growing evidence suggests that vitamin D significantly affects depression. A vitamin-D insufficiency, which is very common even among dedicated supplement users, is linked with seasonal depression. Studies also find that vitamin D3 (cholecalciferol) supplementation can improve symptoms of depression. Recent evidence suggests that vitamin D deficiency also may contribute to general depression through its considerable influence on genetic activity, its ability to control inflammation, and other mechanisms.
Tryptophan: L-tryptohan is essential for the brain to synthesize serotonin (your good mood neurotransmitter), and several studies have shown that acute tryptophan deficiency can cause depression in humans. In fact, some foreign countries license L-tryptophan as an antidepressant. Consumption of diets low in carbohydrate tends to precipitate depression, since the production of brain chemicals serotonin and tryptophan that promote the feeling of wellbeing, is triggered by complex carbohydrate rich foods. In order to properly synthesize and make serotonin, you need sufficient levels of carbohydrates. This is why eating carbohydrates is just as important as eating foods rich in tryptophan for improving mood.
The connection between carbohydrates and mood is all about tryptophan, a nonessential amino acid. As more tryptophan enters the brain, more serotonin is synthesized in the brain, and mood tends to improve. Serotonin, known as a mood regulator, is made naturally in the brain from tryptophan with some help from the B vitamin D. Here’s the catch, though: While tryptophan is found in almost all protein-rich foods, other amino acids are better at passing from the bloodstream into the brain. So you can actually boost your tryptophan levels by eating more carbohydrates; they seem to help eliminate the competition for tryptophan, so more of it can enter the brain. But it’s important to make smart carbohydrate choices like whole grains, fruits, vegetables, and legumes, which also contribute important nutrients and fiber.
Tyrosine: Protein intake and in turn the individual amino acids can affect the brain functioning and mental health. Many of the neurotransmitters in the brain are made from amino acids. The neurotransmitter dopamine is made from the amino acid tyrosine and the neurotransmitter serotonin is made from the tryptophan. If there is a lack of any of these two amino acids, there will not be enough synthesis of the respective neurotransmitters, which is associated with low mood and aggression in the patients.
Chromium: Chromium has been studied for its role in regulating blood sugar by facilitating the uptake of glucose into cells, and some research indicates that it may be beneficial in depression as well. In one case series of five patients with minor depression, chromium supplementation led to remission. Two other pilot studies found chromium picolinate supplementation benefited atypical depression.
Zinc: Zinc is a trace element known to help regulate the nervous system and may be specifically related to depression. Increasing evidence shows that decreased blood levels of zinc are associated with depression, and, in depressed subjects, lower levels of zinc are associated with worse depression.
Probiotics: Emerging research has revealed an important relationship between the gastrointestinal tract and its billions of resident organisms (probiotics, healthy gut bacteria or microbiome) and the brain. This relationship has been termed the “gut-microbiota-brain axis.” Probiotics are organisms which, when consumed in adequate doses, exert a beneficial effect on health. These microorganisms or probiotics produce numerous neurochemicals, including serotonin. 95% of the body’s serotonin is produced in the gut. These neurochemicals made by gut bacteria play a role in mood and other neurologic functions. So balancing gut bacteria through the consumption of probiotics such as Lactobaccilli and Bifidobacteria help to elevate mood. Probiotics, which affect the gut-brain axis, have been shown in preclinical and clinical trials to reduce mood disorders and their symptoms such as stress, anxiety, anger and depression. In fact, probiotics have shown to reduce anxious behaviors to a similar degree as diazepam (Valium).
Selenium: Selenium is a trace mineral that is not commonly adequately consumed. This is an issue since studies are starting to find a connection between selenium deficiency and depression. One study reports, “Our strongest finding was that young adults with the lowest selenium concentrations reported the most depressive symptoms. Although we did not test the physiological mechanisms, other research shows that oxidative damage to the brain and nervous system contributes to the development of depression. Adequate selenium intake is required for optimal antioxidant defenses to protect body tissues from oxidative damage, through glutathione peroxidise, which is a key antioxidant enzyme.”
Other Factors that Increase Risk of Depression
Avoiding the foods that increase the risk of depression: Unfortunately, just like an expensive car, your brain can be damaged if you ingest anything other than premium fuel. If substances from “low-premium” fuel (such as what you get from processed or refined foods) get to the brain, it has little ability to get rid of them. Diets high in refined sugars, for example, are harmful to the brain. In addition to worsening your body’s regulation of insulin, they also promote inflammation and oxidative stress. Multiple studies have found a correlation between a diet high in refined sugars and impaired brain function — and even a worsening of symptoms of mood disorders, such as depression. It makes sense. If your brain is deprived of good-quality nutrition, or if free radicals or damaging inflammatory cells are circulating within the brain’s enclosed space, further contributing to brain tissue injury, consequences are to be expected.
Blood sugar balance and eating breakfast: Eating breakfast regularly leads to improved mood, according to some researchers — along with better memory, more energy throughout the day, and feelings of calmness. It stands to reason that skipping breakfast would do the opposite, leading to fatigue and anxiety. And what makes up a good breakfast? Lots of fiber and nutrients, which are low glycemic foods. Making sure to focus on eating low glycemic foods is essential for keeping the blood sugar balanced which allows your neurotransmitters to work properly.
Who is at risk for Nutrition-based Depression?
Making certain diet choices, taking medication, and having certain lifestyle behaviors can increase your risk for depression. Read through the list below to see if you are at risk.
- Diet made up of primarily processed foods, fried foods, fast food, desserts
- Diet lacking daily intake of multiple servings of vegetables
- Daily or regular intake of “diet” foods and drinks
- Diet lacking protein (animal or plant-based)
- Absence of cold-water fish, hemp seeds, chia seeds, walnuts or omega-3 fatty acid supplement
- Carbohydrate (complex) – free diet (ketogenic, Atkin’s)
- Regular alcohol use
- Regular caffeine use
- Antibiotic use
- Birth control use
- Inadequate sun exposure leading to vitamin D deficiency
- Poor blood sugar balance
The Healthy Mood Diet
Now that we understand how our diet influences mood, let’s see how we can optimize it! Eating the right foods and avoiding the wrong ones can make all the difference. So if you are looking to boost your mood (aren’t we all!) check out the food guidelines for the healthy mood diet to get you on track. Never underestimate the healing power of food!
What Foods and Beverages to Eat
B Vitamins (folate, B12, niacin, B1, B2, and B6):
Leafy greens (kale, collard greens, romaine, arugula, chard), grass-fed organic beef or bison, lentils, beans, asparagus, spinach, organic tempeh, crimini mushrooms, sunflower seeds, organic turkey and sweet potato
Omega-3 Fatty Acids:
Cod, haddock, salmon, mackerell, sardines, halibut, walnuts, hemp and chia seeds and blue green algae (spirulina)
*Omega-3 fatty acids can also be obtained through supplementation. Learn more here.
Pumpkin seeds, cacao (unsweetened chocolate), dark chocolate, spinach, swiss chard, sesame seeds (tahini), almonds, black beans, avocado and figs
Organic turkey, cage-free eggs, spirulina, wild-caught salmon or cod, sesame seeds, cashews and walnuts
Fava beans, organic chicken, organic ricotta cheese, oatmeal, mustard greens, seaweed, dark chocolate and wheat germ
Broccoli, barley, oats, grapes, potatoes, garlic and oranges
Grass-fed organic beef, lamb, sesame seeds, pumpkin seeds, lentils, garbanzo beans, cashews and quinoa
Organic yogurt and kefir, sauerkraut, kimchi, organic tempeh, kombucha, and kvass
Tuna fish, halibut, Brazil nuts (3-4 daily), organic beef, walnuts and poultry
sun exposure and fortified foods such as milk and cereals
*Vitamin D is best obtained through supplementation. Learn more here.
What Foods and Beverages to Avoid
Alcohol: Although the occasional drink is fine, people should limit their alcoholic intake. Heavy alcohol consumption is associated with anxiety and panic attacks; excessive drinking also depletes serotonin, which makes people prone to anxiety and depression.
Caffeine: Caffeinated beverages lower serotonin and increase the risk for anxiety, depression, and poor sleep. Reduce your intake for coffee, caffeinated tea, energy drinks and soda.
Sugar: When you eat processed, refined sugars, you enjoy a momentary high-energy jolt. Eating sweets raises blood sugar level, increases fat storage, and promotes a crash-and-burn feeling. Maintaining a steady blood sugar level is important to achieve even-keeled energy levels. Furthermore, diets higher on the glycemic index (higher sugar levels), including those rich in refined grains and added sugar, were associated with greater odds of depression, the researchers found. Eliminate white sugar, brown sugar, desserts, pastries, ice cream, candy, chocolate bars (other than dark chocolate), sweetened tea and soda. Use stevia instead.
GMO: Genetically engineered (GE) ingredients can significantly alter your gut flora, thereby promoting pathogens while decimating the beneficial microbes necessary for optimal mental and physical health. Make sure to purchase foods that contain the label “non-GMO,” and organic corn and soy, including tempeh, tofu and edamame (the top gmo crops).
Diet Foods (fake sugar): Artificial food additives, especially the artificial sweetener aspartame, can wreak havoc with your brain function. Both depression and panic attacks are known potential side effects of aspartame consumption. Other additives, such as artificial colorings, are also known to impact mood. Avoid all diet and low-calorie foods and beverages including diet tea, diet soda, diet yogurt, diet jam, and diet juice. Eliminate Equal, Splenda and Sweet’N Low.
Gluten: Gluten, a protein found in grains such as wheat, rye, and barley, may negatively impact mood and brain health. In fact, a number of studies indicate that wheat can have a detrimental effect on mood, promoting depression and even more serious mental health problems such as schizophrenia. Avoid gluten grains including wheat, rye, barley and couscous. This includes bread, english muffins, rolls, cakes, pastries, donuts, bagels, crackers, cereal and pasta.
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Happiness & Health: The Biological Factors- Systematic Review Article. Dariush DFARHUD,1,2 Maryam MALMIR,*,3 and Mohammad KHANAHMADI4