For anyone facing demanding routines, a lack of light and distance from nature can be profoundly draining. Yet the science shows that small strategic adjustments to how we live, and to how we interact with our surroundings, have the power to transform our day-to-day wellbeing. Here is how small steps can have an outsized effect on your mental health.
The circadian rhythm: syncing the body clock to sunlight#
Our bodies are governed by rhythms of roughly 24 hours, coordinated by a nucleus in the hypothalamus. This master clock is synchronised by light picked up by ganglion cells in the retina, which suppress the production of melatonin, the sleep hormone, during the day to raise alertness and vitality.
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Wake with natural light: Open the curtains the moment you get up. Morning light is the most effective at advancing your body clock.
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Favour morning light: Morning sunlight is ideal for synchronising the circadian rhythm and regulating mood, and generally carries less harmful UV.
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Your daily dose of sun: Aim for at least 30 to 60 minutes of exposure. Remember that even on an overcast day, outdoor light is far stronger than any indoor lighting.
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Create a digital sunset: Avoid blue light from screens for at least an hour before bed. It suppresses melatonin and fragments your rest.
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Work near a window: Being close to natural light at work lowers anxiety and raises job satisfaction. If your workplace has no daylight, make sunshine the priority on your breaks and days off.
The restorative effect on attention#
Our capacity for directed attention is finite, and it tires quickly under the continual effort of tuning out urban distraction and daily demands. Contact with nature reduces activation of the amygdala, the brain's stress centre, and increases the amplitude of alpha waves, which are associated with alert relaxation.
Recommendations#
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Fifty-minute walks: Forest bathing. Walking in nature improves memory and concentration far more than walking through a busy city centre.
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Fresh air as a tonic: Make fresh air a habit. Choosing green areas improves the quality of the air you breathe, reduces your exposure to urban noise and softens the effect of heat islands in cities.
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Photographic expeditions: Go out with the specific aim of capturing natural things that bring you peace. Focus on detail — the movement of leaves, clouds, patterns on water — or on park-like landscapes of scattered trees and smooth grass. The human mind finds these compositions instinctively restful.
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Digital refuges: If you cannot get out, simply looking at images of nature counters cognitive fatigue and improves performance. Build a gallery on your phone or computer with photographs from walks you have taken, and use images that tie tranquillity to good personal memories as your wallpaper.
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Replace empty walls: Pictures or photographs of nature hung in offices, or in rooms with no window, have restorative effects similar to a real view outside. Decorating your home with them works as a buffer against stress.
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Green micro-breaks: Keep plants indoors. They act as a natural shield against everyday tension.
Chrononutrition and the gut-brain axis#
The gut microbiota shows a daily rhythm strongly influenced by our eating cycle. Circadian misalignment — eating late, or keeping erratic hours — causes a chronodisruption that alters gut bacteria and promotes the systemic inflammation that worsens anxiety. Did you know that around 90% of serotonin is produced in the gastrointestinal tract, under the regulation of these rhythms?
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Align meals with daylight: Eat during daylight hours and avoid late-night snacking. Time-restricted eating, within a window of 8 to 12 hours, keeps the microbiota healthy and supports emotional regulation.
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Psychobiotic eating: Include fibre and fermented foods such as yoghurt and kefir, which feed the beneficial bacteria that produce neurotransmitters.
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Avoid fat late in the day: Diets high in fat in the evening dampen microbial rhythm and disrupt the body-clock genes.
Vitamin D and psychological resilience#
Around 90% of vitamin D is synthesised through the skin's exposure to UVB. It acts as a hormone precursor, with receptors in the areas of the brain responsible for regulating mood. Low levels are consistently correlated with fatigue and poor sleep quality.
Practical tips#
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A minimum sun routine: Expose your arms and legs to the sun for 15 to 30 minutes, four days a week.
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Combine it with exercise: Twenty to thirty minutes of outdoor activity, two or three times a week, maximises both vitality and vitamin synthesis.
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Protection and moderation: Avoid outdoor activity in the two to three hours either side of midday, when UV is strongest and the risk of DNA damage and skin cancer is highest. Wear appropriate clothing that breathes and dries quickly, a hat to cover your head and sunglasses to protect your eyes, and always apply sunscreen.
Conclusion#
To look after your mental and cognitive health:
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Synchronise: Sunlight in the morning, darkness at night.
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Restore: Take breaks in green spaces, or keep indoor plants.
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Eat in time: Eat during the day to support your microbiota.
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Get moving: Combine outdoor walks with sun exposure for a compound effect on anxiety.
References#
An, M., Colarelli, S. M., O’Brien, K., & Boyajian, M. E. (2016). Why we need more nature at work: Effects of natural elements and sunlight on employee mental health and work attitudes. PLOS ONE, 11(5), Article e0155614. https://doi.org/10.1371/journal.pone.0155614
Berman, M. G., Jonides, J., & Kaplan, S. (2008). The cognitive benefits of interacting with nature. Psychological Science, 19(12), 1207–1212. https://doi.org/10.1111/j.1467-9280.2008.02225.x
Beute, F., & de Kort, Y. A. W. (2018). The natural context of wellbeing: Ecological momentary assessment of the influence of nature and daylight on affect and stress for individuals with depression levels varying from none to clinical. Health & Place, 49, 7–18. https://doi.org/10.1016/j.healthplace.2017.11.005
Biggs, A. T., Seech, T. R., Markwald, R. R., & Russell, D. W. (2024). Positive impact of sunlight exposure on mental health in a naval population. Journal of Occupational and Environmental Hygiene, 21(9). https://doi.org/10.1080/15459624.2024.2388535
Codoñer-Franch, P., Gombert, M., Martínez-Raga, J., & Cenit, M. C. (2023). Circadian disruption and mental health: The chronotherapeutic potential of microbiome-based and dietary strategies. International Journal of Molecular Sciences, 24(8), Article 7579. https://doi.org/10.3390/ijms24087579
Spitschan, M., & Zauner, J. (2026). Light exposure as a modifiable determinant of mental health. Current Psychiatry Reports, 28(24). https://doi.org/10.1007/s11920-026-01671-7
