When the Clocks Change: How Nutrition Can Help You Sleep Better
By Dr Timothy Eden, MBBS
Registered Dietitian from Eden Health and Nutrition
Read time approx. 4mins
As the clocks go back and evenings draw in earlier, many of us start to feel our energy dip. It’s not just “winter blues”; the darker days genuinely affect our body clock (circadian rhythm), which controls when we feel alert or sleepy. Less natural light exposure, particularly in the morning, can make it harder to fall asleep at night and lead to groggy mornings.
I wanted to write about this because I see, in both my GP and dietetic practice, just how many people struggle with sleep around this time of year. Often the first response is to reach for caffeine, sugary snacks or comfort foods to push through the fatigue — yet few people realise how profoundly nutrition and routine can influence sleep quality itself.
How Much Sleep Do We Really Need?
Most adults need between 7 and 9 hours of good-quality sleep each night (1). Children and teenagers typically need more, while older adults may find 7 hours sufficient. Importantly, it’s not just the number of hours that matter — it’s the quality of that sleep: how restful, consistent and undisturbed it is.
Sleep allows our brains to consolidate memories, repair tissues, regulate hormones and process emotional experiences. Without it, even small stresses can feel overwhelming, and concentration, energy and mood all take a hit.
Why Sleep Matters So Much for Health
Sleep is sometimes underestimated, but its impact reaches every part of our health. Research shows that regularly sleeping fewer than six hours a night increases risk of a range of long-term conditions, including:
Heart disease and stroke – poor sleep is linked to higher blood pressure, raised inflammatory markers and altered glucose control (2).
Type 2 diabetes and obesity – lack of sleep disrupts insulin sensitivity and increases appetite-regulating hormones, leading to cravings for high-energy foods (3).
Cognitive decline and dementia risk – sleep supports the brain’s glymphatic system, which clears toxins and proteins such as amyloid during deep sleep (4).
Mental health and resilience – reduced sleep heightens stress reactivity, worsens anxiety and low mood, and can lower motivation for physical activity (5).
In short, sleep is a vital pillar of health — just as crucial as nutrition, movement and social connection. NICE guidance recognises good sleep hygiene as a core component of preventive care and self-management (6).
What Is Sleep Hygiene (and Why It Matters Most When the Clocks Change)
The term sleep hygiene refers to the practical habits and environmental factors that promote healthy sleep. Think of it as giving your brain consistent cues for rest — something that becomes particularly valuable when daylight hours change.
Simple evidence-based habits include:
Keeping a consistent sleep–wake routine, even on weekends. The regularity helps your internal clock reset after the hour shift.
A wind-down period — 30–60 minutes before bed doing something calming like reading or stretching, rather than scrolling on a phone.
Reducing blue light exposure in the hour before bed — screens suppress melatonin, the hormone that signals sleepiness.
Making the bedroom a ‘sleep sanctuary’ — quiet, cool (around 16–18 °C), and dark. Avoid working, eating or watching TV in bed.
Limiting stimulants such as caffeine after mid-afternoon, and alcohol close to bedtime, as both impair restorative sleep stages.
Getting daylight in the morning — even a 15-minute walk outdoors helps anchor your circadian rhythm after the clocks change (7).
When we treat sleep as part of lifestyle medicine rather than an afterthought, the improvements in energy, focus and mood can be striking.
The Role of Nutrition in Sleep
Food choices can either work with or against your body clock. The timing, composition and portion size of meals all influence blood sugar stability and the hormones that regulate alertness and rest.
Good Foods to Snack on Before Bed
If you need something before bed, aim for a small, balanced snack that won’t overburden digestion but provides slow-release energy and calming nutrients:
A small bowl of oats or porridge with milk or a fortified plant drink
Banana with a handful of unsalted nuts – combines magnesium and tryptophan
Slice of wholegrain toast with lean turkey or chicken
Greek yoghurt with berries – protein and natural carbohydrate
Warm milk or chamomile tea – comfort and routine without caffeine
These combinations supply tryptophan (the amino acid building block for serotonin and melatonin) plus a little carbohydrate to help it cross into the brain. Magnesium-rich foods such as nuts, seeds and oats also help relax muscles and support nerve function.
Magnesium and Sleep
Magnesium is often called nature’s relaxant. It supports the parasympathetic nervous system and stabilises melatonin production. Most adults need around 300 mg/day (men) and 270 mg/day (women), which can usually be met through a balanced diet (1).
Good sources include:
Leafy greens (spinach, kale)
Nuts and seeds (pumpkin, almonds, sunflower)
Whole grains (brown rice, oats)
Beans and lentils
There is emerging evidence that magnesium deficiency may be linked with poorer sleep quality, though supplementation should only be considered if dietary intake is insufficient or deficiency is confirmed (3).
Foods and Habits That Can Hinder Sleep
Some evening habits are particularly unhelpful if you’re struggling to drift off:
Large, rich meals late at night — can cause reflux or discomfort.
Caffeine — its stimulating effects last 5–6 hours, so even a 4 pm coffee can delay sleep onset.
Alcohol — while it may initially make you drowsy, it disrupts REM sleep and causes early-morning awakenings.
Sugary snacks or desserts — blood-sugar swings overnight can wake you.
Heavy fluids — drinking too much before bed increases night-time waking (especially with worse as we get older).
Keeping your final meal at least two hours before bed helps digestion and allows melatonin to rise naturally.
Tryptophan, Carbohydrates and the Brain
Tryptophan is converted in the body to serotonin (the “feel-good” neurotransmitter) and then to melatonin (the “sleep hormone”). Pairing tryptophan-rich foods such as poultry, fish, eggs, dairy, nuts and seeds with a source of complex carbohydrate (like oats or wholegrain bread) enhances this conversion process (5). That’s why a small turkey/chicken or hummus sandwich on wholegrain bread can genuinely be a sensible bedtime snack — it fuels the ‘chemistry’ of rest.
Why Nutrition and Sleep Work Both Ways
It’s worth noting that poor sleep often drives poorer food choices the following day. When we’re sleep-deprived, the hormones that control appetite (ghrelin and leptin) become dysregulated, increasing cravings for quick-energy foods — typically those high in sugar and refined carbohydrates (3). Think of how you feel after a night of little sleep or a hangover: you’re less likely to fancy porridge and berries, and more likely to reach for pastries or crisps (or takeaways). Over time, this cycle of fatigue, stress and compensatory eating can undermine metabolic health and energy levels.
By improving sleep quality, we often see appetite normalise, caffeine reliance drop and patients report steadier energy throughout the day.
Takeaway Message
As the clocks change and the darker evenings set in, focus on:
Keeping a regular sleep and wake routine
Prioritising daylight exposure during the morning
Creating a calm, screen-free wind-down routine
Choosing lighter, balanced evening meals with magnesium and tryptophan-rich foods
Avoiding caffeine, alcohol and heavy meals near bedtime
Better sleep doesn’t just help you feel refreshed but it supports cardiovascular, metabolic and cognitive health, reduces stress and even helps regulate your food choices the next day. Nutrition and sleep are partners, not separate silos.
References
NHS. Vitamins and minerals – magnesium; How to get good quality sleep. NHS UK, 2024.
Itani O et al. Short sleep duration and health outcomes: a systematic review and meta-analysis. Sleep Med 2017; 32: 246–256.
Chaput J-P et al. Sleep patterns, diet quality and energy balance. Eur J Clin Nutr 2018; 72: 149–156.
Irwin MR, Vitiello MV. Implications of sleep disturbance for Alzheimer’s disease risk. Neurotherapeutics 2019; 16(2): 251-259.
Halson SL. Nutrition and sleep: links to recovery. Sports Med 2014; 44 (Suppl 1): 13-23.
NICE. Sleep and sleep conditions overview. NICE Guidance, 2023.
NHS Every Mind Matters. How to fall asleep faster and sleep better. Public Health England, 2024.