Feeling Tired, Foggy, or Flat? Why Your Energy Levels Feel So Unpredictable

That mid-morning dip, the 3 pm slump that leaves you reaching for cake and coffee, and the foggy, flat feeling that makes you wonder whether it was your lunch, your sleep, or just life catching up.

When energy levels feel unpredictable and you feel tired all the time, it's easy to assume something's wrong with you. In reality, your energy is shaped by several interconnected systems, and when one of these systems is out of balance, the knock-on effects can appear quickly.

In clinic, I see this pattern of chronic fatigue again and again. People often come to see me believing they lack willpower, or that they're not doing enough. More often than not, it isn't about doing more, but supporting the body to keep up with demand.

In this busy, fast-paced world, our bodies are often more depleted than we realise. Chronic stress, poor sleep, and demanding lifestyles can leave you feeling exhausted and experiencing sudden drops in energy levels.

Here are some common causes of fatigue I see, and where it's helpful to start if you're feeling constantly tired during the day.

1. Blood Sugar Balance

If you experience fatigue, energy crashes, sweet cravings, or irritability when meals are delayed, blood sugar regulation is often the first place to look.

Your brain and muscles rely on a steady supply of glucose to maintain energy throughout the day. When meals are unbalanced, heavy on refined carbohydrates and light on protein, fibre, or healthy fats, blood sugar rises quickly and then drops just as fast. That drop in energy levels is what creates the slump and can cause fatigue.

This is where your internal "safety officer" steps in, megaphone in hand, looking for the quickest way to bring those levels back up, which is often chocolate, cake, or energy drinks that provide quick energy but don't sustain it.

Instead, we want to support slower, steadier energy release and boost energy levels naturally. This is why I often start with the idea of a balanced plate:

• A source of protein – around ¼ of the plate
• Colourful vegetables or fibre – around ½ of the plate
• Healthy fats – roughly a thumb-sized portion
• Complex carbohydrates that release energy more slowly (such as brown rice, wholewheat pasta, or sweet potato) – around ¼ of the plate

This balanced diet approach is about giving your body needs the building blocks it requires to sustain energy, rather than chasing it with quick fixes.

2. Absorption Also Matters

What you eat is only half the story. How well you digest and absorb nutrients matters just as much.

Eating on the go, rushing meals, scrolling through emails, or eating under stress keeps the nervous system in "fight or flight" mode. In that state, digestion is not a priority, which can disrupt how your body processes nutrients.

Creating simple habits, such as slowing down, taking a deep breath before eating, chewing properly, and giving yourself space to eat, may sound basic, but they directly affect how effectively nutrients are broken down and absorbed.

Without this, even the most nutrient-dense diet can fall short and leave you feeling fatigued despite eating well.

3. Sleep and Stress

Poor sleep quality and chronic stress quietly drain energy reserves and are among the most common causes of fatigue.

Sleep is when the body repairs, detoxifies, and resets hormone signalling. Without adequate hours of sleep or quality sleep, you may feel tired the next day, struggle to fall asleep the following night, and experience persistent fatigue that affects both mental and physical health.

Chronic conditions like sleep apnea or other sleep disorders can also disrupt sleep patterns and negatively affect sleep quality, leaving you feeling chronically tired even after what seems like enough rest.

Chronic stress, on the other hand, increases the demand for nutrients, particularly magnesium and B vitamins, while simultaneously impairing digestion and blood sugar balance. This combination can cause extreme fatigue and feelings of exhaustion.

This is why someone can be eating well and still experience fatigue. The system is simply working harder behind the scenes, and stress and anxiety may be exacerbating fatigue.

I've found that using the NUYU Magnesium Sleep Spray as part of my bedtime routine helps me begin to feel ready to wind down in the evening, which can be particularly helpful during busier or more stressful periods when getting good sleep feels harder. Ten sprays provide around 30% of your daily magnesium intake and can help support your sleep cycle.

4. Nutrient Status: Supporting What's Already There

Nutrients such as vitamin B12 and magnesium play an essential role in energy production, nervous system function, and mental clarity. Low levels can contribute to tiredness and fatigue, brain fog, and reduced resilience to stress – all physical symptoms that could be a sign of nutrient deficiencies.

In clinical practice, I always advocate for testing where possible, because everyone's needs are different, and understanding what your body and mind actually require matters. This is particularly important if you're experiencing sudden episodes of fatigue or extreme tiredness that doesn't improve with rest.

That said, many people struggle to maintain optimal nutrient levels due to modern lifestyles, ongoing chronic stress, and depleted food soils. This lack of energy from nutritional gaps is a common cause of fatigue that's often overlooked.

This is where high-quality supplements can play a supportive role to help boost your energy, not as a replacement for food or lifestyle changes, but as a way of supporting the system while foundations are being rebuilt.

Think of supplements as scaffolding: useful, temporary support that works best when the bigger structure is being addressed.

The Bigger Picture: It's Not Just One Thing

If your energy levels feel inconsistent and you feel exhausted regularly, it's rarely about one single health condition or medical issue. More often, it's a combination of blood sugar balance, digestion, sleep quality, stress load, and nutrient demand all working together.

While feelings of fatigue are normal to feel tired after a long day or during particularly demanding periods, persistent tiredness during the day or feeling drained constantly may be a sign that your body needs more support.

Fatigue is often caused by:

• Poor sleep patterns and sleep deprivation
• Chronic stress affecting both mental and physical health
• Blood sugar imbalances from an unbalanced diet
• Nutritional deficiencies affecting energy production
• Dehydration (a surprisingly common cause of low energy)
• Underlying mental health conditions like depression or anxiety and depression
• Physical health issues or chronic conditions that disrupt normal function

Starting with the balanced plate is often the simplest first step to boost energy levels naturally. Notice how you're feeling throughout the day, then layer in changes gradually – better sleep hygiene, stress management, regular physical activity, and staying hydrated – until your energy returns and you help you feel better.

If fatigue persists despite these changes, or if you're experiencing extreme fatigue that makes it difficult to get out of bed or complete daily tasks, it's important to speak with a healthcare professional. Sometimes persistent fatigue could be a sign of conditions like chronic fatigue syndrome, sleep apnoea, or other medical conditions that require professional support to help you develop strategies for managing symptoms.

Remember: it's normal to feel tired sometimes, but feeling tired all the time or experiencing sudden, extreme tiredness isn't something you have to live with. With the right support for both your body and mind, sustainable energy is possible.

Learn More About Claire - www.nourishtosoar.co.uk