Food and Mood

HK BioTek Intern

Food is one of the basic necessities for our survival as being the source of energy for us to sustain our body function and health. However, food is also necessary for our psychological well-being. Many of us should have experienced hanger (anger when hungry) or the crave for any comfort food during bad mood for stress relief. One example of the food that people crave during stress or sadness would be junk food like potato chips and ice cream. Indeed, it is scientifically supported that certain food can calm people down but not every food would have the same effect on emotions.

On the other hand, it is suggested that poor nutrition including long-term high intake of sugar from food or beverages would pose negative effects to our mental health by influencing the inflammation level and the brain cells. Apart from that, carbohydrates are also susceptible to bad mood, among which food with high glycemic index could actually lead to some detrimental effects to our mental well-being, such as depression symptoms or anxiety. By lowering down the glucose concentration in our blood, and then triggering the release of some hormones which can result in anxiety symptoms, such as irritability and hunger. One of the hormones released is cortisol, which is known as the stress hormone, negatively affecting both physical and psychological conditions and thus the mood will be affected. Therefore, food definitely plays a role in our mood and mental state.

Types of food resulting in better mood

Polyphenol food group

Polyphenols are a group of plant metabolites found in mainly fruits and vegetables as well as some snacks in our diet. It is found that food as great source of polyphenols would lower the level of cortisol. Apart from lowering such level, polyphenols can also inhibit the activity of certain enzyme which is involved in the activation of cortisol. As a result, the level of active cortisol would be reduced and so as the stress level. Not only that, polyphenols can also suppress the activity of another enzyme which thus lead to an antidepressant effect. One well-known food source of polyphenols is chocolate and it is common that people would link it to happiness or crave for it in hard times.

Food sources of polyphenols	Examples
Berries	Blueberry, Blackcurrant, Strawberry
Herbs and spices	Cloves*, Peppermint*, Oregano*
Cocoa	Cocoa powder, Milk chocolate
Seeds	Flaxseed, Chestnut, Hazelnut

*Not significant due to the little amount consumed each time

Apart from the above food items, polyphenols can also be obtained in beverages with lesser amount, such as red wine, grape juice, orange juice, and tea etc. This can also tell why some people love to drink a glass of wine or a cup of tea after a long day of work.

Mediterranean diet

Studies have also shown that the Mediterranean diet can lower the chance of getting some psychological conditions such as depression. Mediterranean diet emphasizes the high consumption of fruits, vegetables, nuts and legumes, moderate consumption of poultry, eggs and dairy products as well as occasional consumption of red meat. From physiological perspective, depressive symptoms can be associated with the dietary inflammation from poor eating habits. Although the mechanisms behind are still not well understood, studies have observed that the depressive symptoms can be relieved by some anti-inflammatory substances. Similar to those substances, Mediterranean diet and polyphenols or other healthy dietary patterns with anti-inflammatory property can possibly relieve the depressive symptoms as well. Therefore, it is important for us to consume nutritious food and establish healthy eating habits. Not only improve our health status but also ensure a good mental state.

Food options for Mediterranean diet	Examples
Whole grains	Whole wheat, oat, brown rice, pasta, quinoa, corn, etc.
Vegetables	Broccoli, cauliflower, spinach, kale, peppers, cucumber, etc.
Fruits	Avocado, apple, banana, orange, kiwi, fig, etc.
Meat	Chicken, turkey, salmon, tuna, clam, shrimp, mussel, etc.
Legumes	Lentils, hummus, peas, beans, peanuts, etc.
Nuts and seeds	Almond, walnut, cashew, hazelnut, chia seed, etc.
Dairy	Milk, cheese, Greek yogurt, etc.

Apart from the consumption of the above food, it is also necessary to eat withing our recommended calorie intake instead of eating excessive amount. This applies to the consumption of polyphenol-rich food too. In the meantime, we should also minimize the intake of added sugar, unhealthy oil, refined grains and processed food. In a nutshell, we can see the association between food and our emotions. What is your comfort food and are you craving for them now?

Reference:

1. Firth, J., Gangwisch, J. E., Borisini, A., Wootton, R. E., & Mayer, E. A. (2020). Food and mood: how do diet and nutrition affect mental wellbeing?. BMJ (Clinical research ed.), 369, m2382. https://doi.org/10.1136/bmj.m2382

2. Gunnars, K. (2018). Mediterranean Diet 101: A Meal Plan and Beginner’s Guide. Healthline. https://www.healthline.com/nutrition/mediterranean-diet-meal-plan

3. Haskell-Ramsay, C.F., Stuart, R.C., Okello, E.J. et al. Cognitive and mood improvements following acute supplementation with purple grape juice in healthy young adults. Eur J Nutr 56, 2621–2631 (2017). https://doi.org/10.1007/s00394-017-1454-7

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

5. Perez-Jimenez, J., Neveu, V., Vos, F. & Scalbert, A. (2010). Identification of the 100 richest dietary sources of polyphenols: an application of the Phenol-Explorer database. European Journal of Clinical Nutrition, 64, 112-120. https://www.nature.com/articles/ejcn2010221.pdf?origin=ppub%20content

6. Tsang, C., Hodgson, L., Bussu, A., Farhat, G., & Al-Dujaili, E. (2019). Effect of Polyphenol-Rich Dark Chocolate on Salivary Cortisol and Mood in Adults. Antioxidants (Basel, Switzerland), 8(6), 149. https://doi.org/10.3390/antiox8060149

7. Ulrich-Lai, Y. M., Fulton, S., Wilson, M., Petrovich, G., & Rinaman, L. (2015). Stress exposure, food intake and emotional state. Stress (Amsterdam, Netherlands), 18(4), 381–399. https://doi.org/10.3109/10253890.2015.1062981