Food and mood

The interaction between mood and diet is complex. For example, people with anxiety and depression tend to consume food rich in sugar and salt and high in fat. Also, it is often difficult for people with mental health issues to find the energy required to choose a recipe, shop for ingredients, and prepare healthy food. All this can lead to increased consumption of processed foods. To close the circle, we know that an unhealthy diet can lead to inflammatory, metabolic and immune changes affecting the chemical mediators in the brain- specifically tryptophan (a precursor of serotonin) and GABA. There is evidence that all these changes can affect mood and anxiety levels.

I would like you to know about the SMILES trial[1] conducted in Australia between 2015-2017 by Prof Felice Jacka and her team. The study was a randomised control trial of dietary improvement for adults with major depression. The SMILES trial proved that a modified Mediterranean diet (ModiMed diet) could improve severe depression.

The ModiMed diet recommends complex carbohydrates such as wholegrain cereals accompanied by multiple daily serves of fruits and vegetables, nuts, seeds, olive oil and dairy, and several weekly serves of legumes, red meat, fish, poultry and eggs. Processed food is limited to 3 serves per week (for example, one portion of dessert, one sweetened beverage, and one small pack of crisps per week). ModiMed diet is rich in all B vitamins hence promoting nervous cell regeneration. Turkey meat, tuna, and chicken are rich in tryptophan. Fruits and vegetables are rich in polyphenols, beta carotene, vitamin C and vitamin E, known to reduce oxidative stress and protect the brain against the damaging action of advanced glycation end products.

Some studies have reported a link between low selenium and poor moods. The recommended amount for selenium is 55 micrograms per day for adults.

People with low omega-3 levels may have higher rates of major depressive disorder. Good sources of omega-3s are anchovy, mackerel, salmon, sardines and tuna, all of which are staples of the Modi Med diet. Vegan sources of omega-3 acids are seaweed, algae, chia seeds, hemp seeds, flaxseeds, walnuts and kidney beans.Two important fatty acids are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). EPA and DHA have distinct roles and actions in the body. High levels of EPA will reduce inflammation in the body and brain. DHA increases the transmission of signals from the membrane's surface to the nerve cells' interior[2].

Between 2019 and 2021, an international task force involving 31 leading academics and clinicians from 15 countries developed clinical guidelines regarding the therapeutic use of nutrient-based 'nutraceuticals' and plant-based 'phytoceuticals' for the treatment of mental disorders. To create the guidelines[3], the expert panel considered Grade A level evidence - meta-analysis or two or more RCTs to determine whether the intervention was 'Recommended' (+++), 'Provisionally Recommended' (++), 'Weakly Recommended' (+), 'Not Currently Recommended' (+/-), or 'Not Recommended' (-) for a particular condition

Here are the recommendations :

Unipolar depression - none of the nutraceuticals and phytoceuticals considered are recommended as monotherapy; however omega-3 fatty acids (+++), vitamin D (+), adjunctive probiotics (++), adjunctive zinc (++), methylfolate (+), and adjunctive s-adenosyl methionine (SAMe) (+) are recommended as adjunctives as well as St John's wort (+++), saffron (++), curcumin (++), and lavender (+)

Bipolar depression - omega-3 had weak support for bipolar depression (+), while NAC was not currently recommended (+/-)

Schizophrenia- for the treatment of negative symptoms: Vitamin D (+), NAC (++), methylfolate (++) were recommended, while omega-3 fatty acids were not, although evidence suggests a role in the prevention of transition to psychosis in high-risk youth, with potential pre-existing fatty acid deficiency

ADHD - Micronutrients (+) and vitamin D (+) were weakly supported

Anxiety disorders: Ashwagandha (++), galphimia (+), and lavender (++)

The task force also noted that while the safety and tolerability levels were acceptable, a critical limiting issue was the quality and standardisation of phytoceuticals.

Manufactured herbal medicines placed on the UK market since April 2011 must have either a Traditional Herbal Registration (THR) or a Marketing Authorisation (MA).

I hope you enjoyed reading about the ModiMed diet and the evidence-based recommendations for nutraceuticals and phytochemicals. Contact me if you want to discuss this in more detail

[1]https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-017-0791-y [2] HTTPS://WWW.PSYCHOLOGYTODAY.COM/BLOG/IN-THE-ZONE/201204/WHAT-ARE-THE-REAL-DIFFERENCES-BETWEEN-EPA-AND-DHA [3] https://pubmed.ncbi.nlm.nih.gov/35311615/