Eating for Mood
Autumn is a great time for supporting the gut, with warming foods like porridge and soups and rituals like stewing apples. But it is also the time of year when many people find their good moods disappearing along with the summer sun.
It is estimated that around 2 million people in the UK suffer from Seasonal Affective Disorder (SAD), a condition linked to reduced sunlight, which can interfere with the production of mood-regulating neurotransmitters such as serotonin (Royal College of Psychiatrists, n.d.; Patient.info, 2023; Health Assured, 2023).
While there isn’t much we can do about daylight hours in the UK during autumn/winter, we can support mood via nutrition and lifestyle during this transitional phase.
Go Easy on Digestion by Choosing Warm Foods
Cold foods can be harder to digest, especially as the weather cools. Warm foods may help stimulate digestive secretions (e.g. gastric juices and enzymes), giving the digestive system a gentler workload and promoting comfort. Think hearty soups, stews and porridge with warming spices such as cinnamon or ginger.
Blood Sugar Balance Matters
“Blood sugar” refers to the amount of glucose circulating in the bloodstream. After you eat:
Some glucose is used immediately by cells for energy.
Excess glucose is stored in muscles and the liver as glycogen.
Any leftover is stored as fat.
The brain, though only ~2 % of body weight, uses ~20 % of glucose-derived energy (Merlo et al., 2024). Large spikes and crashes in blood sugar can lead to periods where the brain feels “under-fuelled,” contributing to irritability, fatigue and mood dips. Keeping blood glucose steady by having balanced meals with protein, healthy fats and fibre-rich carbohydrates supports more stable mental energy.
Nutrients That Support Mood
Tryptophan is an essential amino acid found in turkey, eggs, dairy, oats and seeds used to synthesize serotonin in the brain.
Healthy fats / Omega-3s are long-chain omega-3 fatty acids (e.g. EPA, DHA) from oily fish, flaxseed, chia and walnuts which support membrane fluidity, neurotransmission and anti-inflammatory pathways implicated in mood regulation (Raza et al., 2025).
B vitamins, especially B6, B12 and folate are co-factors in neurotransmitter synthesis and energy metabolism.
Gut Health and Microbiome Support
A thriving gut microbiome is increasingly implicated in mental health. The gut–brain axis describes bidirectional communication via neural, endocrine and immune pathways. Diet is a major modulator of the gut microbiome and changes in microbial composition have been associated with depressive symptoms (Horn et al., 2022; Bear et al., 2022; Clerici et al., 2025).
Eating a diverse array of plant foods (prebiotic fibre), fermented/probiotic-rich foods (yogurt, kefir, sauerkraut) and limiting ultra-processed foods supports microbial diversity and, in turn, mental well-being.
Consider Vitamin D*
Vitamin D, often classed as a prohormone, plays roles in brain health, immune function and neuromodulation. Low levels are common in autumn and winter in the UK and have been associated with depressed mood, possibly via effects on serotonin, inflammation and neurotrophins (Raza et al., 2025).
*Always consult a qualified health professional before starting any supplements, including vitamin D.
Exercise and Movement
Even a single bout of exercise has been shown to acutely improve mood, reduce perceived stress and enhance resilience to negative emotional states. Regular physical activity is associated with lower rates of depression and anxiety in many studies (Merlo et al., 2024).
Light & Routine
Light exposure: Light is a key signal in circadian regulation and serotonin/melatonin balance. Getting outside in daylight (even 20–30 minutes) or using a light therapy box / sunrise alarm clock may mitigate seasonal mood dips (Royal College of Psychiatrists, n.d.).
Routine: Keeping stable sleep–wake times, regular meal patterns and scheduling daily movement or nature exposure are helpful adjuncts to nutritional strategies.
References
Bear, T.L.K., Dalziel, J.E. and Coad, J. (2022) ‘The role of the gut microbiota in dietary interventions for depression’, Trends in Molecular Medicine, 28(3), pp. 223–235.
Clerici, C., Verzeletti, G. and Carabelli, A. (2025) ‘Gut microbiome, diet and depression: Literature review’, Current Nutrition Reports, 14(1), pp. 15–28.
Health Assured (2023) Seasonal Affective Disorder (SAD) affects over 2 million people in the UK. Available at: https://www.healthassured.org (Accessed: 3 October 2025).
Horn, S.R., Long, M.M. and Berger, M. (2022) ‘Role of diet and its effects on the gut microbiome in psychiatric disorders’, Translational Psychiatry, 12(1), pp. 1–11.
Merlo, L., Gualtieri, F. and Marinelli, L. (2024) ‘Gut microbiota, nutrition, and mental health’, Frontiers in Nutrition, 11, 1412563.
Patient.info (2023) Seasonal Affective Disorder (SAD): Symptoms and treatment. Available at: https://patient.info (Accessed: 3 October 2025).
Raza, A., Khan, F. and Yousaf, T. (2025) ‘The role of vitamin D and omega-3 fatty acids in modulating depression pathways’, Neuroscience & Biobehavioral Reviews, 162, 105081.
Royal College of Psychiatrists (n.d.) Seasonal Affective Disorder (SAD). Available at: https://www.rcpsych.ac.uk (Accessed: 3 October 2025).
