Nutrition and Mental Health

Diet and Mental health: Exploring the Link

An Introduction

The foods we consume serve as more than just fuel for our bodies; they directly influence the structure and function of our brains. Nutritional psychiatry explores the complex interplay between nutrients, neural pathways, and the biochemical processes that influence mental health and well-being (1).

Nutritional psychiatry not only provides valuable insights to optimize brain function but is also paving the way for innovative therapies. It is helping to unravel new strategies for treating neurodegenerative conditions by embracing nutrition as an integral part of patient care (2). As our understanding of nutritional psychiatry grows, individuals can make informed choices to nurture their brains through mindful eating. By harnessing the power of food, we can unlock the potential to improve mental health outcomes, protect against brain disorders, and ultimately, lead healthier, more vibrant personal and academic lives.

Anxiety, Depression and the Mediterranean Diet

A large body of research shows a relationship between diet quality and mental health. Better diet quality seems to decrease the risk of mental health conditions such as depression.

Emerging research has recently demonstrated the therapeutic impact of diet on mental health(3)(4). Among the many dietary patterns studied, the Mediterranean diet (MedDiet) emerges as a promising approach to promoting positive mental well-being.

The Mediterranean diet, inspired by the traditional dietary habits of countries bordering the Mediterranean Sea (Spain, Southern Italy, etc.), emphasizes the consumption of whole, minimally processed foods. This diet is characterized by a high intake of fruits, vegetables, legumes, whole grains, lean proteins (such as fish and poultry), and healthy fats, notably from olive oil and nuts. Moderate consumption of dairy products, specifically yogurt and cheese, is also a key component (5). This body of scientific evidence suggests that adhering to the Mediterranean diet is associated with a lower risk of mental health disorders, including anxiety and depression. Several mechanisms help explain this relationship. Firstly, the diet is rich in nutrients important for brain health, including omega-3 fatty acids, B vitamins, vitamin D, antioxidants, and minerals such as magnesium and zinc. These nutrients play critical roles in maintaining the structure and function of the brain and regulating mood and are often lacking in Western diets (1).

Secondly, the Mediterranean diet's emphasis on whole foods and healthy fats provides anti-inflammatory benefits. Chronic inflammation has been implicated in the development and progression of mental health disorders (6). By reducing inflammation, the diet may help modulate the body's immune response, contributing to improved mental well-being (1).

Long-term dietary patterns such as the MedDiet can also play a key role in shaping gut microbiota(7). Though the exact mechanisms haven’t been discovered, there is also evidence that gut microbiota can directly and indirectly modulate brain function (6). One of the suggested mechanisms is through the modulation of neuroactive pathways including neurotransmitter generation (6). The Mediterranean diet's inclusion of healthy fats, such as olive oil and nuts, supports the production of neurotransmitters like serotonin which play crucial roles in regulating mood (7). The diet's high intake of fruits and vegetables also provides essential phytochemicals and fibre that help promote a healthy microbiome (7).

While more research is needed to establish a definitive causation between the Mediterranean diet and mental health outcomes, the existing evidence is highly encouraging. It suggests that adopting this dietary pattern may be a valuable adjunctive approach to managing anxiety and depression.

It is important to note that many of the participants in the clinical trials using diet as a treatment for depression or anxiety used the diet change in addition to their existing treatment strategies of medication, therapy or both. Adopting this dietary pattern may be a valuable approach to managing anxiety and depression or promoting mental well-being. Incorporating the principles of the Mediterranean diet into one's lifestyle, alongside professional support, exercise, and other self-care strategies, can contribute to overall mental wellness. As the understanding of the link between diet and mental health deepens, it becomes increasingly clear that food choices matter beyond physical health. The Mediterranean diet offers a promising way to nourish both the body and the mind, providing a foundation for positive mental well-being.

Sources:

(1) Rao TSS, Asha MR, Ramesh BN, Rao KSJ. Understanding nutrition, depression and mental illnesses. Indian J Psychiatry. 2008;50(2):77–82.

(2) Polidori MC, Stahl W, Griffiths HR. Nutritional cognitive neuroscience of aging: Focus on carotenoids and cognitive frailty. Redox Biology [Internet]. 2021 [cited 2023 Dec 2];44. Available from: https://journals.scholarsportal.info/details/22132317/v44inone/nfp_ncnoafocacf.xml

(3) Parletta N, Zarnowiecki D, Cho J, Wilson A, Bogomolova S, Villani A, et al. A Mediterranean-style dietary intervention supplemented with fish oil improves diet quality and mental health in people with depression: A randomized controlled trial (HELFIMED). Nutr Neurosci. 2019 Jul;22(7):474–87.

(4) Aucoin, M., LaChance, L., van der Wurff, I. et al. Dietary counselling plus omega-3 supplementation in the treatment of generalized anxiety disorder: protocol for a randomized wait-list controlled pilot trial (the “EASe-GAD Trial”).                     Pilot Feasibility Stud 9, 186 (2023). https://doi.org/10.1186/s40814-023-01414-y

(5) Davis C, Bryan J, Hodgson J, Murphy K. Definition of the Mediterranean Diet; A Literature Review. Nutrients. 2015 Nov;7(11):9139–53.

(6) Gialluisi A, Bonaccio M, Di Castelnuovo A, Costanzo S, De Curtis A, Sarchiapone M, et al. Lifestyle and biological factors influence the relationship between mental health and low-grade inflammation. Brain, Behavior, and Immunity. 2020 Mar 1;85:4–13.

(7) Marx W, Lane M, Hockey M, Aslam H, Berk M, Walder K, et al. Diet and depression: exploring the biological mechanisms of action. Mol Psychiatry. 2021 Jan;26(1):134–50.