What you eat affects not only your physical health but also your mental health. Eating some foods can improve your mood and mental wellbeing, while other foods can have a negative impact on how you feel.
Key points
The link between food and mood is clear: what you eat affects your mental wellbeing. In fact, poor diet may not only be a reaction to feeling depressed, but may be one of the factors that trigger it.
If you are feeling depressed or anxious, you are more likely to want to eat more unhealthy foods (such as potato chips and takeaways) and eat fewer healthy foods (such as fresh fruit and vegetables).But, eating unhealthy foods can actually make you feel worse.
You can improve your mental wellbeing by making changes to your diet. And luckily, the same eating habits that keep you mentally well are those that support your physical health too.
Choose a diet high in vegetables, fruits, unprocessed grains and fish, with smaller portions of lean meat and dairy – and limit those sugary, salty and processed foods.
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How does what I eat affect my mood?
Just as sleep and exercise are key to feeling good, food also affects your mood. Like the rest of your body, your brain needs fuel to function. And just like filling up your car, putting in the right kind of fuel is key to how well your brain performs – including how well you are mentally and emotionally.
A recent study showed that the more people improved their food choices, the more their depression improved. Food is linked to the hippocampus, a key area of your brain involved in learning, memory and mental health. People with healthy diets have more hippocampal volume than those with unhealthy diets.
As well as your brain, your gut is the other part of your body that plays a key role in your mood. Everything you eat passes through your intestine (gut). Your gut is home to billions of bacteria and other mircroorganisms (bugs), known as your gut microbiome. These bugs are involved in many functions critical to your health and wellbeing. Therefore, eating foods that support your gut microbiome will support your mental health. Read more about gut health and mental health.
Although we don’t yet know exactly which bugs are needed for the optimal mix of gut bacteria, we do know that greater diversity of bugs is associated with better health outcomes. And what promotes a greater variety of gut bugs? The simple answer: fibre-rich whole-foods.
How to manage your mood with food – 8 tips
(Mind, the mental health charity, UK, 2018)
What foods will improve my mood?
Food choices that meet the Eating and activity guidelines for NZ Adults, as well as Mediterranean eating patterns, can reduce the risk of getting depression. What does that look like in terms of food? To quote food author Michael Pollan: “eat food, not too much, mostly plants”.
Eat food, mostly plants
“Eat food” means to eat real food – vegetables, fruits, nuts and seeds, whole grains, fish and meat – and avoid highly processed foods. People who eat a diet high in whole foods are up to 35% less likely to develop depression than people who eat less of these foods. A University of Otago study found that young adults who ate more fruit and vegetables for just 2 weeks increased their feelings of vitality and wellbeing.
Rather than only eating cooked fruit and vegetables, each day have some of them raw.
An eating pattern that includes a wide range of foods includes the following:
vegetables (eg, carrots, dark leafy greens, cucumber)
fruits (eg, bananas, apples, citrus, berries)
legumes (eg, lentils, chickpeas, beans)
wholegrains (eg, rice, oats, breads)
nuts and seeds
oily fish and lean meats
good oils (eg, most plant-based oils).
If you eat a wide range of foods the nutrients should take care of themselves, including the main nutrients associated with depression:
Omega 3 fatty acids – because of its anti-inflammatory properties and effects on transmitting the hormones dopamine and serotonin, omega 3 has a role in brain development and functioning. If you don’t have enough omega-3, it can contribute to mental health problems.12 These are found in oily fish (salmon, tuna, sardines and anchovies, plant-based oils, walnuts, flax and chia seeds and dark green leafy veggies, as well as some fish oil supplements.
B group vitamins – these help regulate neurotransmitters and immune function. They can be found in green leafy veggies, legumes and whole grains. B12 is in fish, beef, lamb, poultry, eggs and milk and some fortified breakfast cereals.
Vitamin D – for optimal brain function, mood and critical thinking – and present in fatty fish, eggs, dairy foods and sunlight!
Not too much
Cut down on sugar, salt and highly processed foods (eg, takeaway meals, packaged snack foods and processed or smoked meats).
Limit caffeine (which may cause or exacerbate anxiety).
If you drink alcohol, reduce your long-term health risks by drinking no more than:
2 standard drinks a day for women and no more than 10 standard drinks a week
3 standard drinks a day for men and no more than 15 standard drinks a week.
This should include at least 2 alcohol-free days every week.
The following links provide further information about food and mood. Be aware that websites from other countries may have information that differs from New Zealand recommendations.
Julie Carter works as a liaison dietitian for the Auckland District Health Board. She has an interest in public health nutrition.
Credits: Health Navigator Editorial Team . Reviewed By: Julie Carter, registered dietitian, Auckland DHB
Last reviewed: 12 Aug 2019
How does gut health affect mental health?
Everything you eat passes through your intestine (gut). Your gut is home to billions of bacteria and other micro-organisms (bugs), known as your gut microbiome. These bugs are involved in many functions critical to your health and wellbeing. A healthy gut microbiome:
provides a strong barrier against toxins and “bad” bacteria
aids absorbtion of nutrients from your food (digestion)
supports the functioning of neurons (nerve cells) that line your gut wall
helps reduce inflammation.
Your gut microbiome also activates a neural pathway that travels directly between your gut and your brain, called the gut–brain axis.Because of this pathway, the food you digest in your gut affects the messages sent to your brain. This means that what is happening in your digestive system affects your emotional and mental wellbeing. Therefore, eating foods that support your gut microbiome will support your mental health.
What foods support a healthy gut microbiome?
Although it's not yet known exactly which bugs are needed for the ideal mix of gut bacteria, it is known that greater diversity of bugs is associated with better health outcomes. And what promotes a greater variety of gut bugs? The simple answer is fibre-rich whole-foods.
Fibre-rich whole foods help support a healthy gut. These include plant foods such as vegetables, fruit, whole-grains, legumes, nuts and seeds.
You can also promote a healthy gut by eating bacteria itself in the form of fermented food such as kimchi, kefir and sauerkraut.
The benefits of eating fibre-rich food or fermented food only last for as long as you are eating them (or shortly thereafter).
This means that if you want to get their health-benefiting rewards, you need eat them every day and ideally with every meal.
Simple ways to increase dietary fibre intake include swapping white bread or white rice for wholegrain bread or brown rice, or snacking on fruit or adding a cup of mixed vegetables with lunch or dinner.
A day-to-day diet lacking in fibre starves the gut microbiome and can lead to them eating the mucus that lines and protects your gut wall. Evidence suggests that if your gut microbiome consume too much of your gut wall, damaging inflammatory processes may kick in.
Food for Thought: The Relationship Between Food, Gut and Brain Future Learn (paid course) 4 hours a week for 5 weeks This course is open to everyone, but may be of particular interest to psychologists or people working in health and well-being. No previous experience is required, though a background knowledge of biology or psychology may help.
Information for healthcare providers on food and mood
The content on this page will be of most use to clinicians, such as nurses, doctors, pharmacists, specialists and other healthcare providers.
What does the research say about diet and mental health?
The authors of a meta-analysis of 41 previous studies into mental health and diet found such strong associations, including a likely causal link between diet and depression, that they recommend GPs discuss diet with patients. There was a robust association between both higher adherence to a Mediterranean diet and lower adherence to a pro-inflammatory diet and a lower risk of depression. Also they found that an extensive body of evidence now points to the microbiome-gut-brain axis as playing a key role in neuropsychiatry, and to the primacy of diet as a factor modulating this axis Lassale C, Batty GD, Baghdadli A et al. Healthy dietary indices and risk of depressive outcomes – a systematic review and meta-analysis of observational studies
People with some kind of mental health problem eat fewer healthy foods (such as fresh fruit and vegetables, organic foods and meals made from scratch) and more unhealthy foods (chips and crisps, chocolate, ready meals and takeaways). Diet and mental health Mental Health Foundation, UK
A diet high in refined sugars is related to poorer brain functioning and worsening mood disorders, such as depression. The risk of depression is 25% to 35% lower in those who eat a traditional diet high in vegetables, fruits, unprocessed grains, and fish and seafood, and only modest amounts of lean meats and dairy, an little or no processed and refined foods and sugars. Nutritional psychiatry – your brain on food Harvard Health, US, 2015
Researchers into the relationship between unhealthy dietary patterns and poorer mental health in children and adolescents observed a consistent trend for the relationship between good-quality diet and better mental health. O’Neil A, Quirk SE, Housden S, et al. Relationship between diet and mental health in children and adolescents – a systematic review Am J Public Health. 2014 October; 104(10): e31–e42.
In the Australian SMILES (Supporting the Modification of lifestyle in Lowered Emotional States) Trial, randomised controlled trial, Australian researchers found that after 12 weeks a third of those in the dietary support group had significantly improved mood and symptoms, compared with only 8% of those in the group receiving social support. The diet was a modified Mediterranean diet (ModiMedDiet) to include some low fat dairy and lean red meat SMILES trial Food & Mood Centre, Australia, 2016; Opis RS, O’Neil A, Jacka FN, Pizzinga J & Itsiopoulos C. A modified Mediterranean dietary intervention for adults with major depression – dietary protocol and feasibility data from the SMILES trial J Nut Neurosci. 2017 Apr; 21(7):487–501.
A notable feature of the diets of patients suffering from mental disorders is the severity of deficiency in nutrients. Studies have indicated that daily supplements of vital nutrients are often effective in reducing patients' symptoms. Sathyanarayana Rao TS, Rao, Asha MR, Ramesh BN, Jagannatha Rao KS. Understanding nutrition, depression and mental illnesses Indian J Psychiatry. 2008 Apr-Jun; 50(2): 77–82.
Because of its anti-inflammatory properties and effects on dopamine and serotonin transmission, omega 3 has a role in brain development and functioning, with deficiencies linked to mental health problems. The link between food and mental health American Psychological Association, 2017
Online course
Food and Mood: Improving Mental Health Through Diet and Nutrition Future Learn NZ (paid course) 3 hours a week for 3 weeks This is an introductory course which might be of interest to healthcare practitioners working with people with mental and brain health issues or in roles related to diet, nutrition and mental and brain health education.
Regional HealthPathways NZ
Access to the following regional pathways is localised for each region and access is limited to health providers. If you do not know the login details, contact your DHB or PHO for more information:
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