how does food affect your mood?

Along with unstructured days, foggy brain, cluttered thoughts and everchanging moods can impact on your productivity and enjoyment throughout your day. Our Registered Nutritional Therapist and Health Coach Jane Barnes looks at the link between food and moods
 
Covid has been a daily topic of conversation for us all for the last 18 months, but the Olympics and the honesty and openness of athletes like Simone Biles has highlighted a second epidemic that has been building quietly for a while – that of our challenges around mental health.

Data from NHS Digital showed that 70.9 million prescriptions for antidepressants were given out in 2018, compared with 36 million in 2008 1. Even more alarmingly, the statistics showed that 23% more patients received an antidepressant item in the third quarter of 2020–2021 compared to the same quarter in 2015–2016 2.

Clearly, there is a huge problem ……. but the good news is that there are many things we can do that may help to improve our resilience and protect our mental health.  Research is beginning to show that our diet and lifestyle choices can have a big impact. In fact, there is a burgeoning discipline called nutritional psychiatry with a small but growing body of evidence behind the gut-brain connection.
 
It has long been proposed that eating the Mediterranean diet may offer protection against various health complaints including depression. It was not until 2017, however, that the SMILES trial 3 was able to demonstrate a more direct relationship between food and mood. During the trial, a group of adults with moderate depression were allocated randomly to two groups. One group received seven sessions of individual dietary advice and support from a dietician based around eating the Mediterranean diet, while the other group received seven social support sessions. After 12 weeks, the dietary advice group had significantly reduced their depression symptoms and by significantly more than the social support group.
 
Several more studies have subsequently demonstrated improvements in depression or anxiety scores after a Mediterranean dietary approach was instituted – with bigger benefits seen in moderate to severe depression compared to mild depression.

So, what is the Mediterranean diet and how might it be helping to combat depression?
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The Mediterranean diet is rich in colourful plant foods, wholegrains, nuts, seeds, and olive oil with moderate amounts of fish and white meat but only small amounts of red meat and dairy foods.

It is notably low in sugar, refined carbohydrates (white bread, pasta, rice etc), and saturated or trans fats.

An inflammatory mechanism is one theory for what causes mental health disorders, in fact some scientists are now questioning whether antidepressant medications such as SSRIS may primarily be beneficial because they have anti-inflammatory effects in the brain. Interestingly, the plentiful coloured plant pigments, high fibre content and omega-3 fats in the Mediterranean diet all add up to a powerful anti-inflammatory cocktail which helps to combat the raised inflammatory markers that are often observed in people with depression and anxiety.
 
In addition to being anti-inflammatory, the low content of sugar and refined carbohydrates in the Mediterranean diet supports better blood sugar balance. Having poorly controlled blood sugar levels or a diet high in sugar and refined carbohydrates are both known risk factors for developing depression or other mental health disorders 4.
 
Plant fibre is important for good gut health – and there is increasing evidence for the link between gut health and brain health. Gut microbes produce chemicals that can act directly on the brain to influence mood and it is clear from animal studies that changing the pattern of gut microbes can influence behaviour. It is also a little-known fact that the gut makes large quantities of the same neurotransmitters that are used in the brain - although it is currently unclear exactly how these may be acting on the brain. Eating a Mediterranean diet is certainly associated with having a much more diverse and healthier pattern of gut microbes.
 
Finally, the quality protein from fish and white meat provides essential amino acids and other nutrients that the body needs to make neurotransmitters without high levels of the more inflammatory fats that are found in red meat and dairy products. 

So, what does it all add up to?
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Following these few simple dietary rules may help to increase your resilience and lower your risk for developing mental health problems.

• Eat an entire rainbow of different coloured plant foods every day – the different coloured plant pigments are packed full of antioxidants, nurture healthy gut bacteria and have anti-inflammatory effects.
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• Eat foods that contain omega-3 fats such as oily fish (eg. salmon, sardines, anchovies, trout, mackerel, herring) walnuts, chia seeds or flax seeds. Omega-3 fats may also help support anti-inflammatory processes in the body.

• Reduce your consumption of sugar and refined carbohydrates (white bread, pasta, rice, and processed foods). Instead, get your carbohydrates from vegetables, fruit, wholegrains and pulses (eg lentils, beans and chickpeas) which may help to stabilise your blood sugars and also contain essential vitamins and minerals.
  
  
• Reduce coffee and alcohol consumption as these may both increase levels of stress hormones and raise anxiety levels.
  
  
• Regularly include foods with good sources of the essential amino acids tryptophan and phenylalanine which are needed to make the (happy and calming) neurotransmitters serotonin and GABA.
  • Tryptophan (chicken, turkey, red meat, pork, tofu, fish, beans, milk, nuts, seeds, oatmeal, and eggs).
  • Phenylalanine (beef, chicken, pork, tofu, fish, beans, milk, nuts, seeds, whole grains, and vegetables like sweet potatoes).
    
    
• Regularly including fermented foods such as sauerkraut, live yoghurt, kimchi, kefir, tempeh, miso and kombucha may help to promote a healthy balance of gut bacteria.
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In conclusion, although most of us will not find ourselves competing at the Olympics anytime soon, following the above guidelines and eating a healthy anti-inflammatory diet may help to increase resilience and improve mood as well as our overall feeling of wellbeing. For anyone who struggles to implement this or needs more help with their mental health I offer personalised dietary and lifestyle advice, supplement protocols and coaching. Please contact me via the contact form on my website or ask at the reception at Personal Best.
 
Future articles will cover the importance of lifestyle factors such as exercise, sleep, stress and social connection on mental health.
 

1. Iacobucci G. NHS prescribed record number of antidepressants last year BMJ 2019; 364 :l1508 doi:10.1136/bmj.l1508
2. The Pharmaceutical Journal, PJ, March 2021, Vol 306, No 7947;306(7947)::DOI:10.1211/PJ.2021.1.62125
3. Jacka, F.N., O’Neil, A., Opie, R. et al. A randomised controlled trial of dietary improvement for adults with major depression (the ‘SMILES’ trial). BMC Med 15, 23 (2017). https://doi.org/10.1186/s12916-017-0791-y
4. Knüppel, A., Shipley, M.J., Llewellyn, C.H. et al. Sugar intake from sweet food and beverages, common mental disorder and depression: prospective findings from the Whitehall II study. Sci Rep 7, 6287 (2017). https://doi.org/10.1038/s41598-017-05649-7