By Sue Bedford (MSc Nutritional Therapist)
As the darker months draw in, many of us begin to feel the effects of reduced daylight — sluggishness, low mood, or even symptoms of depression. For some, this seasonal dip can develop into a more significant condition known as Seasonal Affective Disorder (SAD), a form of depression that occurs during certain times of the year, typically from October to April.
SAD affects millions of people worldwide, particularly in the northern hemisphere where sunlight is limited during winter. Studies estimate that between 1% and 10% of the population may experience SAD, with higher rates in areas further from the equator.
While some people experience mild “winter blues,” others may struggle with debilitating fatigue, anxiety, and depression. The main trigger is thought to be a lack of sunlight, which disrupts the body’s production of key hormones and neurotransmitters that influence mood, sleep, and overall wellbeing.
What Causes Seasonal Affective Disorder (SAD)?
SAD is believed to result from a combination of factors, including:
- Reduced exposure to natural light
- Imbalance in serotonin (the “feel-good” hormone)
- Disrupted circadian rhythm or body clock
- Stress and biological predisposition
- Low levels of vitamin D
Women and individuals with a family history of depression are more likely to experience SAD. To be diagnosed, symptoms must appear during the same season for at least two consecutive years.
Common Symptoms of SAD
- Low energy and motivation
- Overeating or sugar cravings
- Weight gain
- Social withdrawal
- Feeling sleepy or oversleeping
- Anxiety or low mood
Nutrition and SAD: Supporting Your Body and Mind Naturally
Optimising your nutrition and lifestyle can make a huge difference in how your body and brain cope with the darker months. Here’s how to naturally boost your mood and energy this winter — and support your fertility in the process.
Vitamin D — The “Sunshine Vitamin”
Vitamin D is essential for hormone balance, immune function, and mood regulation — all key factors for fertility and mental health. It’s produced when your skin is exposed to UVB rays from sunlight, but in the UK and northern climates, we don’t get enough sunlight between October and April.
Low vitamin D has been linked to low mood, fatigue, and infertility.
Top sources of vitamin D:
- Egg yolks
- Oily fish (salmon, sardines, herring, mackerel)
- Red meat and liver
- Fortified foods (milk, cereals, orange juice)
💡 Tip: Choose a supplement that contains vitamin D3 (cholecalciferol) — the same form naturally produced by your skin. Ask your GP or a registered nutritional therapist for guidance and testing.
Omega-3 Fatty Acids
Omega-3s are essential fats that support brain health, reduce inflammation, and boost serotonin production. Research links low omega-3 levels with anxiety, depression, and poor cognitive function.
Top sources: oily fish, nuts, seeds, avocado, and grass-fed eggs or meat.
Eat Quality Protein
Protein provides amino acids — the building blocks for neurotransmitters like serotonin and dopamine, which regulate mood. Include lean protein with every meal:
- Eggs
- Chicken or turkey
- Fish
- Legumes and pulses
- Nuts and seeds
Turkey, in particular, contains tryptophan, which helps produce both serotonin and melatonin, supporting better sleep and mood.
Support Serotonin Production
Serotonin is your body’s natural mood stabiliser. To boost it naturally, eat foods rich in tryptophan, such as:
- Oats and dairy
- Poultry and fish
- Sesame and sunflower seeds
- Almonds, chickpeas, and peanuts
- Bananas (also great for promoting calm and better sleep)
Boost Antioxidants and B Vitamins
B vitamins — especially B6, B12, and folate — are vital for brain function and mood balance. Deficiencies are linked to fatigue, anxiety, and depression.
Good sources: leafy greens, lentils, eggs, fortified cereals, salmon, and dairy.
Combine these with antioxidant-rich fruits like berries, which can help reduce the effects of stress by lowering cortisol (the body’s stress hormone).
Cut Back on Sugar, Alcohol, and Caffeine
It’s tempting to reach for sugary treats or extra coffee when you’re tired or low, but these cause blood sugar spikes and crashes that can worsen mood swings and fatigue.
Swap processed snacks for:
- A handful of nuts and seeds
- Oatcakes with hummus
- Natural yoghurt with berries
Move Your Body and Get Outdoors
Exercise is a powerful natural antidepressant. Just 20–30 minutes of brisk walking each day can help increase endorphins, balance hormones, and improve sleep.
Whenever possible, get outside during daylight hours to maximise your exposure to natural light.
Prioritise Mind-Body Wellbeing
Stress reduction is key to both emotional wellbeing and fertility health.
Incorporate small daily practices to help you stay grounded:
- Meditation or mindfulness
- Deep breathing exercises
- Gentle yoga or stretching
- Gratitude journaling
Final Thoughts
The darker months can be tough — but with the right nutrition, self-care, and support, you can nurture both your mood and your fertility health.
Remember, if you’re struggling with low mood or anxiety, don’t hesitate to reach out to your GP, counsellor, or qualified nutritional therapist. You don’t have to face this alone.
🌿 About Sue Bedford (MSc Nutritional Therapist)
Sue is a leading fertility and nutritional therapist, specialising in women’s health, fertility nutrition, and emotional wellbeing. She helps individuals and couples improve fertility and overall health through personalised nutrition and lifestyle plans.
💬 Want to find out more?
Chat with Sue Bedford to explore how nutrition and lifestyle changes can boost your mood, energy, and fertility this winter.
