Is nutrition good for mental health?
In honor of May as Mental Health Awareness Month, we’re breaking down the effect of diet and nutrition on mental health. Research on the link between diet and mental health is constantly evolving. The emergence of the field of nutritional psychiatry aims to identify dietary components important for mental health and provide appropriate suggestions for dietary modifications or supplements that prevent or manage mood disorders. [1]
Mental health issues are quite common, with one in five adults in the United States experiencing mental illness; understanding how nutrition can be good for mental health is vital. [2]
Let’s dive into the link between nutrition and mental health and learn how you can use diet to improve mental wellbeing.
What is mental health?
Mental health encompasses social, emotional, and psychological wellbeing, affecting our emotions, actions, and thinking. Mental health also influences how we deal with stress, interact with others, and make healthy choices. Mental health is essential throughout life, from childhood and adolescence through adulthood and old age. [2]
Both mental and physical health are important for overall health. Poor mental health can impact dietary habits and physical health. Alternatively, poor physical health and chronic diseases can affect mental health. [2]
How does nutrition impact the brain and mental health?
What you eat can affect cognitive function and mental health. The brain has high metabolic and nutrient needs, using about 20% of your daily caloric intake. Sufficient fuel (calories) and vitamins and minerals are required for the brain to carry out important processes that influence mental health. For example, producing neurotransmitters (chemical messengers that carry signals from one nerve cell to another) requires folate and B vitamins. Omega-3 fatty acids are essential to many of the central nervous system’s functions, including regulating neurotransmitters (such as norepinephrine, dopamine, and serotonin) and neurons (nerve cells) production and survival. [3]
What is the effect of diet and nutrition on mental health?
While evidence shows an association between specific nutrients and mental health, there is a growing trend to look at the relationship between dietary patterns and mental health, as we rarely eat food in isolation. Dietary patterns high in processed foods may be positively associated with depression, mild cognitive impairment, and attention deficit hyperactivity disorder (ADHD). Alternatively, dietary patterns that emphasize whole foods or the Mediterranean diet may be protective against the onset of depression and other mental illnesses. [3,4]
Let’s explore the effects of these diets on mental health.
A healthy dietary pattern may be good for health
A healthy dietary pattern primarily consisting of fruits, vegetables, whole grains, poultry, fish, and reduced-fat dairy is associated with a reduced chance of experiencing depression. [5]
A meta-analysis (a compilation of the results of multiple studies) of prospective cohort studies (a research study that tracks a group of people over time) found that higher adherence to a healthy, high-quality diet was associated with a 23% reduced risk of developing depression compared to lower adherence to a healthy diet. Another review found higher adherence to a healthier dietary pattern was linked with a reduced risk of depression and improved mental health in middle-aged and older people with a current or previous diagnosis of depression.
One caveat with the research on healthy dietary patterns for mental health: the benefit may depend on the severity of the person’s depression symptoms.
Ultra-processed foods may negatively impact mental health
A greater intake of ultra-processed foods (UPFs) may be associated with worse mental health. UPFs contain five or more ingredients rarely or never used in home cooking (typically additives). UPFs are generally low-cost, shelf-stable, convenient, and highly palatable. [6] Moreover, UPFs tend to be energy-dense (containing a high amount of calories per given weight), full of fat, sugar, and salt, and without many micronutrients. [7]
One meta-analysis of cross-sectional studies (observational research studies that look at groups of people at one specific point in time) of more than 185,000 participants found a greater intake of UPFs was associated with a 53% increased risk of depressive and anxiety symptoms compared to lower consumption of UPFs. A prospective study of more than 26,700 participants confirmed these findings: study participants who consumed the most UPFs were 30% more likely to experience depressive symptoms than participants who consumed the least amount of UPFs. Moreover, each 10% increase in the percentage of UPF in the diet was associated with a 21% greater risk of depressive symptoms.
Not all studies agree with the results of these two studies. For example, one meta-analysis of prospective cohorts did not find an association between adherence to an unhealthy dietary pattern and the occurrence of depression. Furthermore, cross-sectional studies (like the ones included in some of these meta-analyses) have limitations: they only show correlation and not causation. They cannot assess the directionality of the relationship between diet and mental health (whether diet leads to mental health issues or whether mental health issues result in dietary changes). Additional research is necessary to elucidate the relationship between diet and mental health, particularly the directionality of this association.
Nutrient composition could be the link between nutrition and mental health
As mentioned throughout this article, nutrition can affect mental health positively or negatively. Inflammation may mediate the relationship between diet and mental health. Healthy diets tend to contain anti-inflammatory foods (such as fruits, vegetables, legumes, and nuts and seeds), which may benefit mental health. Conversely, a diet high in inflammatory foods (such as refined flour, added sugar, high-fat products, and processed meats and foods) may negatively affect mental health.
A healthy dietary pattern is rich in antioxidants and anti-inflammatory foods, which may be the beneficial link between nutrition and mental health. Antioxidants (compounds that can prevent or delay cell damage) found in fruits and vegetables may reduce oxidative stress-related damage to neurons. [5] Accumulation of damage from oxidative stress has been implicated in mental and cognitive health issues. [8] Other anti-inflammatory properties associated with a healthy diet may affect monoamine (specific types of neurotransmitters) concentrations, which can influence emotions and cognition. [5]
Alternatively, there may be a link between a diet high in inflammatory foods and poor mental health. The Dietary Inflammatory Index (DII) is a scoring system used to assess the effect of food on inflammation within the body. One meta-analysis of more than 55,300 participants from cross-sectional and prospective studies found an association between the highest category of DII and symptoms of depression, anxiety, and distress. Furthermore, every 1-unit increase in DII was associated with a 6% greater risk of symptoms of depression. This would suggest that diets high in inflammatory foods appear to be related to mental health disorders.
How can nutrition improve mental health and wellbeing?
You can take steps to use nutrition to improve mental health and wellbeing. Specifically, you can follow an overall healthy diet (as previously discussed) and ensure you get enough of specific nutrients linked to optimizing good mental health.
What are key nutrients to support mental health?
Inadequate nutrient levels can contribute to poor mental health. Nutrient deficiencies can lead to feelings of low mood, fatigue, cognitive impairment, and irritability —all symptoms associated with depression and dementia. [3] So ensuring your diet is full of specific nutrients — such as B vitamins (including folate) and omega-3 fatty acids — may provide a boost to help improve mental health and wellbeing.
At Nutrition Digested, we take a food-first approach, emphasizing nutrient-dense foods and conducting additional assessments (like blood tests) before evaluating the need for supplements.
B vitamins may benefit mood
There is some research supporting the benefit of B vitamins for mood. B vitamins play a key role in many metabolic pathways, including preventing the accumulation of homocysteine. High homocysteine levels are a risk factor for poor mood, with homocysteine levels often elevated in people experiencing depression. Additionally, B vitamins are involved in synthesizing and regulating dopaminergic and serotonergic neurotransmitters. Research suggests that supplementing with B vitamins may benefit depression and anxiety; with baseline nutrient status and dietary habits appearing to influence the effectiveness of B vitamins. [9]
If you want to optimize your B vitamin status to support mental health, try incorporating more foods with B vitamins into your diet. Many grains and cereals are enriched with B vitamins. However, vitamin B12, which is particularly important for mental health, is predominantly found in animal-based foods, such as beef and beef liver, clams, tuna, salmon, eggs, milk, and yogurt. For a plant-based alternative, try nutritional yeast, which is an excellent source of vitamin B12. Sprinkle nutritional yeast on salads, soups, or pasta dishes to get some of this key nutrient.
Omega-3 fatty acids may help reduce depressive symptoms
Omega-3 polyunsaturated fatty acids can slow age-related cognitive impairment and help reduce inflammation, stress, anxiety, and depression. In particular, two forms of omega-3 fatty acids, Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), are important for mental health, as both forms are essential for brain health and function. Adequate intake of omega-3 fatty acids can also protect against neurodegenerative dementia, as higher levels of EPA and DHA are associated with lower declines in cognition and memory. [1]
A meta-analysis of double-blind randomized placebo-controlled trials (the gold standard for nutrition research) of more than 2100 participants found supplementing with omega-3 fatty acids benefitted depression symptoms. Specifically, EPA-dominant supplements — defined as either 100% pure EPA or an EPA-dominant formulation containing more than 60% EPA — had a clinically significant benefit on depression symptoms when taken in doses of ≤1 gram per day. Doses more than one gram per day don’t appear to have a greater effect on depression symptoms.
You can improve your intake of omega-3 fatty acids by eating more fatty fish, the primary source of EPA and DHA. Try seaweed, which contains tiny amounts of EPA and DHA, for a plant-based option. Omega-3 fatty acids in plant-based foods are primarily alpha-linolenic acid (ALA), which the body can convert into EPA and DHA. Plant-based sources of ALA include flax, chia, and hemp seeds (and their oils), walnuts, and soybean and canola oils. Opt for fatty fish (like salmon) every so often, or incorporate more plant-based sources by topping salads, cereal, or bowls with seeds.
Nutrition Digested does not encourage the use of supplements without prior health assessments. Supplements should only be taken once cleared by your medical provider.
How to use nutrition to improve mental health
You can use nutrition to improve mental health and wellbeing by following a healthy dietary pattern that includes sufficient amounts of B vitamins, omega-3 fatty acids, and antioxidants while limiting processed foods. It is best to improve nutrition through food instead of supplements. Below are tips on how to use nutrition to improve mental health and wellbeing.
- Try incorporating more plant-based foods into your diet. For example, try a bean and whole-grain-based dish one evening instead of eating meat.
- Sprinkle seeds or nuts on your salads, cereals, or oatmeal.
- Snack on fruit, vegetables, or nuts and seeds instead of chips.
- Incorporate more legumes into your diet. Legumes are a great plant-based protein source associated with longevity and reduced risk of chronic diseases. Add legumes to salads or make them the focus of your meal by creating stews, soups, or bean-based burgers.
- Try nutritional yeast. It’s great on soups, salads, and popcorn!
Key takeaways
- Nutrition affects mental health, with some foods having a beneficial effect and others having a more negative impact.
- Dietary patterns are associated with improved or worse mental health. Prioritizing healthy eating patterns rich in fruit, vegetables, whole grains, nuts and seeds, and lean protein can benefit mental health. Conversely, diets abundant in processed foods, added sugar, and saturated fat can negatively affect mental health.
- Some nutrients like B vitamins and omega-3 fatty acids may be associated with improved mental health. Try to incorporate foods rich in these nutrients.
- More research is needed to understand the direct impact of specific nutrients on mental health and depressive symptoms.
Want to learn more about how you can use nutrition to benefit your mental health? Get in touch with us!
The information presented here is for educational and informational purposes only. It is not to be used to diagnose or treat any health conditions. If you have questions about the information presented, please contact your healthcare provider.
References
[1] https://pubmed.ncbi.nlm.nih.gov/33763446/
[2] https://www.cdc.gov/mentalhealth/learn/index.htm
[3] https://pubmed.ncbi.nlm.nih.gov/25958655
[4] https://pubmed.ncbi.nlm.nih.gov/24468939/
[5] https://pubmed.ncbi.nlm.nih.gov/24196402/
[6] https://pubmed.ncbi.nlm.nih.gov/35807749/
[7] https://pubmed.ncbi.nlm.nih.gov/30982472/0
[8] https://pubmed.ncbi.nlm.nih.gov/34026809/
[9] https://pubmed.ncbi.nlm.nih.gov/31527485/