Dr Linia Patel PhD looks at how the food you eat affects your mood and why that is particularly relevant today.
We have a pandemic. An economic recession looms. On top of that, the globe continues to warm up. If you think too much about it, it’s depressing! Unsurprisingly, mental health has definitely become a priority for many people and will continue to be so this next year.
How foods you eat affect how you feel
Nutritional psychiatry has been a growing area of research over the last 10 years. Studies show that people eating ‘traditional diets’ such as the Mediterranean diet or the traditional Japanese or South African diet, when compared to a typical standard America diet (SAD diet) or a ‘western’ diet, have a 25-35% lower risk of experiencing depression1,2,3! Researchers put this difference down to the fact that western-type diets tend to be higher in processed and added sugar, whereas traditional diets tend to be high in whole, unprocessed foods and, in general, are higher in fibre2, which is a key nutrient for your gut3.
Gut feelings – how food affects how you feel
What you eat directly affects the structure and function of your brain and, ultimately, your mood. However, in recent years, food and mood has been focused on in an indirect way. More specifically, through the gut-brain axis. Key players in this axis are your gut bacteria. They not only determine how well you absorb nutrients from your foods, but they limit inflammation, activate neural pathways that travel directly between the gut and the brain, and determine how much serotonin is produced3. Serotonin is a neurotransmitter that helps regulate sleep, appetite and mood. More than 90% of your serotonin receptors are located in the gut. Low levels of serotonin in the brain may cause anxiety, depression and problems with sleep3.
Very commonly as children we are taught about ‘treat foods’ and to use food as a reward, so unsurprisingly as adults we continue to associate eating some foods with pleasure and reward (comfort food, carbohydrates, chocolate, etc.) or, on the contrary, eating ‘diet’ foods with deprivation. Physiologically, eating carbohydrates is also known to boost your serotonin levels. This may be one reason why low carbohydrate (i.e., high-protein or high-fat diets) lead to low mood4. While some of our favourite foods may be comforting, it is not ideal to strongly connect food with emotion, as it can lead to emotional and stress eating.
Other pieces of the puzzle
Eating more nutrient-dense foods can help your mood that’s for sure, but it’s only a piece of the puzzle. You cannot eat your way out of feeling anxious, stressed or depressed. You also need to make sure you move, sleep enough, connect with loved ones, address your pattern of thinking and reach out for professional help if you need more support. Please remember that, when this article talks about mood problems, it is referring to mild and moderate forms of depression and anxiety4.
Eat yourself happy tips1,2,3,5,6
- Make friends with fibre. Since your gut bacteria are so integral in determining the amount of the feel-good hormone serotonin that is made, you need to make sure you keep them well-nourished as well. Gut bacteria like fibre-rich foods. Ensure that your diet does not eliminate carbs, but rather includes wholegrains, beans and lentils, as well as a variety of vegetables and fruit.
- Go easy on the processed food. Highly processed foods, which are high in food additives and preservatives, disrupt the healthy bacteria in your gut, so keep these foods to a minimum.
- Eat at regular times. Steady and stable blood sugar levels help you stay focused. Avoid skipping meals, particularly when you are feeling the stress. Eat at regular intervals.
- Start with oats. Oats provide fibre that helps stabilise your blood sugar levels and boost your mood. They are also high in iron, which may improve mood symptoms in those with iron deficiency anaemia.
- Become a fish fan. Oily fish like sardines, mackerel or salmon are rich in omega-3 fatty acids, which may lower your risk of depression. Make sure you eat fish at least twice a week and make one portion oily.
- Try fermented foods. Foods like bio-live yogurt, kefir, miso, sauerkraut and pickles are rich in probiotics, which support the growth of healthy bacteria in your gut. Include at least one fermented food in your diet daily.
- Get beany with it! Beans and lentils are rich in B vitamins (particularly B3 and B6), which help to synthesise feel-good neurotransmitters like dopamine and serotonin.
- Have a handful of nuts a day. Nuts like brazil nuts, almonds and pine nuts are particularly high in zinc, selenium and tryptophan – all these nutrients support brain function and lower your risk of depression.
- Indulge in chocolate. Dark chocolate (>70%) is rich in many mood-boosting compounds such as theobromine and N-acylethanolamine, which have all been linked to improved mood. The bonus is that research also shows that the bitterness in chocolate is also thought to help diminish cravings for sweet things.
- Discover non-food-related ways to comfort yourself. Have a candlelit bath, buy yourself some flowers, get out in nature, call a friend … discover the things that give you joy without added calories.
Where to next? Find out if you would be healthier if you didn’t drink
Dr Linia Patel has a BSc degree in biochemistry and physiology and has recently achieved a PhD in public health. Linia is a leading dietitian and sports nutritionist. Her passion is translating nutritional science into easy-to-digest and practical advice. @liniapatelnutiriton
- Firth J (2020), Food and mood: how do diet and nutrition affect mental wellbeing?, BMJ,
- Zepf F et al (2015), Food and your mood: nutritional psychiatry, Lancet Psychiatry, 2(7): 19.
- Giles G (2018), Sugar intake and expectation effects on cognition and mood, Exp Clin Psychopharmacol, 26(3): 302-309.
- Hulsken S et al (2013), Food derived serotonergic modulators: effect on mood and cognition, Nutrition Research Reviews, 26: 223.
- BDA Food and Mood Factsheet, https://www.bda.uk.com/resource/food-facts-food-and-mood.html, accessed on 11 February 2021.
- Arab A (2019), The association between diet and mood: a systematic review of current literature, Psychiatry Res, 428-37