Tired This Winter? How Food Intolerances Affect Energy & Sleep

Tired This Winter? How Food Intolerances Affect Energy & Sleep

Written by: Molly Harvey-Love Nov 11, 2025

In this article

As the days get shorter and darker, it’s common to feel a little more tired and sluggish. Many people notice their energy dips, sleep becomes lighter or more disrupted, and motivation starts to fade. While the winter months naturally bring some changes in mood and routine, persistent fatigue or low energy can be a sign that your body is struggling with something deeper, such as hidden food intolerances.

If you often wake up groggy, rely on caffeine to get through the day, or feel bloated and irritable after meals, it may not just be the time of year. What you eat, and how your body responds to it, can have a big impact on energy, hormones, and sleep quality.

Let’s look at how inflammatory foods can affect your body’s natural rhythms, why some evening favourites might be making things worse, and what you can do to restore balance and feel more energised this winter.

The gut and hormone connection

Your gut does far more than digest food. It plays a central role in producing and regulating key hormones that influence how you feel day to day, including serotonin and cortisol. When your gut is inflamed or irritated by certain foods, that communication network becomes disrupted.

Serotonin:

Around 90% of this “feel-good” neurotransmitter is made in the gut. It helps regulate mood, digestion, and sleep. When your gut lining is inflamed, serotonin production can fall out of balance, leading to mood swings, low motivation, and disrupted sleep cycles.

Cortisol: 

This is your main stress hormone, but it also affects energy regulation. Chronic low-grade inflammation from food intolerances can keep cortisol slightly elevated, which makes it harder to fall asleep, stay asleep, and wake up refreshed.

Over time, this can create a pattern of feeling wired but tired, exhausted during the day but unable to fully rest at night.

How inflammatory foods affect sleep

Inflammatory reactions don’t always feel dramatic. You may not notice a clear link between what you eat and how you sleep, but your body often does. Hidden intolerances can lead to subtle changes in your sleep patterns through:

  • Digestive discomfort: Bloating or indigestion after certain foods can interfere with deep, restorative sleep.
  • Blood sugar swings: Foods high in refined carbs or sugars can cause energy spikes followed by drops, leading to nighttime waking or early morning fatigue.
  • Hormonal disruption: Gut inflammation can affect melatonin production (your sleep hormone), making it harder to fall asleep naturally.
  • Stress signalling: Even mild digestive stress can trigger your body’s fight or flight response, keeping cortisol elevated overnight.
If you find yourself waking around 2 or 3 a.m., feeling restless, or needing snacks or caffeine to get through the day, your body may be telling you that certain foods aren’t sitting well.

Common evening culprits

Many foods and drinks that feel comforting at the end of a long day can also be the ones most likely to disrupt digestion, mood, and sleep. Three of the most common culprits are:
  • Wine: Even small amounts of alcohol can affect blood sugar stability and suppress REM sleep. For those with food intolerances, sulphites or yeast in wine may also trigger inflammation or bloating.
  • Cheese: A frequent trigger for people with dairy sensitivities, cheese can contribute to congestion, headaches, or digestive sluggishness that affect rest and recovery.
  • Chocolate: A favourite evening treat, but it contains both caffeine and theobromine, natural stimulants that can keep the nervous system active long after you switch off the lights. It also often contains dairy, another common intolerance trigger.

If you tend to enjoy these in the evening, try taking a short break from them for a week or two and see how your sleep and mood respond.

 

Signs your energy and sleep issues could be linked to food intolerances

Food intolerances don’t always cause obvious digestive symptoms. You might notice some of the following instead:
  • Afternoon energy crashes
  • Poor concentration or brain fog
  • Feeling heavy or bloated after meals
  • Low mood or irritability
  • Restless sleep or waking in the night
  • Feeling tired even after a full night’s sleep
These are signs that your body is working harder than it should to process certain foods, creating a background level of inflammation that affects your hormones, energy, and recovery.

Nutritionist tips for rebalancing energy naturally

If you suspect food intolerances are behind your low energy or poor sleep, the first step is to create more stability for your body to recover.

  1. Start your day with protein and fibreA balanced breakfast with protein such as eggs, yoghurt, or chia pudding and slow-release carbohydrates like oats or quinoa helps stabilise blood sugar and energy levels throughout the day.
  2. Reduce evening stimulantsCaffeine, alcohol, and sugar can all interfere with sleep quality. Try herbal teas such as chamomile, passionflower, or lemon balm to wind down naturally.
  3. Eat anti-inflammatory foodsFocus on colourful fruits and vegetables, olive oil, avocado, flaxseed, turmeric, and oily fish. These support both gut and hormone balance.
  4. Support your gut microbiomeInclude fermented foods like sauerkraut, kimchi, or kefir if tolerated, and plenty of fibre from beans, lentils, oats, and vegetables. A healthy gut helps regulate serotonin and cortisol naturally.
  5. Prioritise rest and routineAim for consistent mealtimes and sleep times. Your body thrives on rhythm, and stability helps reset hormonal patterns linked to energy and sleep.

 

Testing Takes the Guesswork Out

Because intolerances can vary so much from person to person, testing can be a valuable way to uncover what’s really draining your energy. Sometimes the culprit isn’t what you’d expect, such as a healthy food you eat regularly that could be causing hidden stress on your system.

By identifying and removing the foods that are inflaming your gut, you can support hormone balance, stabilise energy, and improve sleep naturally.

 

Key Takeaway

If every day feels like an uphill battle with low energy, bloating, or restless nights, it might not just be the winter blues - it could be your body reacting to hidden food intolerances. Once you understand what’s behind the fatigue, you can take simple steps to restore balance and feel like yourself again.

Find your hidden triggers with our Intolerance Test - a quick, non-invasive way to identify foods that may be disrupting your energy, mood, and sleep.

More articles

Gut-skin connection: How digestive resilience improves skin
Gut-skin connection: How digestive resilience improves skin
Oct 16, 2025