Tired all the time but blood tests are normal? Here’s what your body might be telling you

Feeling exhausted but your blood tests are normal? This blog explores five hidden reasons for persistent fatigue.

You’ve done everything “right.” You booked the blood test, showed up fasting, waited for results, only to be told everything looks “normal.”

But here’s the thing: you still feel wiped out. You’re struggling to get through the day without caffeine, wondering why your brain feels foggy, why your gut’s unpredictable, and why you don’t feel like yourself, whoever that is anymore.

If this sounds familiar, you’re not alone. Every week, I speak to women who’ve been told their results are fine but feel anything but. When your labs say one thing but your energy levels says another, it’s time to look beyond the basics.

This post explores five common but overlooked reasons why you might feel fatigued, even when your blood tests are “normal”, and what to do next.

Why normal blood tests don’t always mean you're thriving

Most routine blood tests are designed to detect disease, not dysfunction. They’re excellent at identifying when something is severely off, anaemia, diabetes, thyroid disease, but not as helpful at spotting subtler imbalances that affect your energy, hormones, or nervous system.

Let’s be clear: normal doesn’t always mean optimal. And it definitely doesn’t mean your symptoms don’t matter.

Hidden signs your body is struggling (even if labs look fine)

Here are five subtle but meaningful signs that your body may need more support, even if everything looks okay on paper.

1. You feel you’re getting enough sleep, but still waking up exhausted

Getting 7–9 hours of sleep should help you feel restored. But if you wake up feeling groggy, sluggish, or like you haven’t slept at all, it might be more than a bad night’s rest.

Possible contributors:

Low ferritin (iron storage): Many women feel depleted when ferritin is under 70 ug/L, even though NHS ranges consider 40+ acceptable.
Magnesium deficiency: Essential for muscle relaxation and deep sleep, but often missed on standard tests.
Blood sugar swings: Night wakings around 2–3am can signal a dip in blood glucose.

💡 Tip: Ask for a full iron panel (not just ferritin), and consider testing magnesium and fasting insulin or HbA1c. Keeping blood sugar balanced with protein and fibre-rich meals can also improve sleep quality.

2. Your mood is low or anxious, but your B12 looks normal

Mood changes like irritability, anxiety, or brain fog aren’t just emotional, they often reflect what’s going on biochemically. Nutrients like B6, B12, and folate are needed for neurotransmitter production and nervous system function.

Even if your B12 is “in range,” symptoms can appear when levels fall below 700 pmol/L in some people. And if you're not absorbing well (due to low stomach acid, medications, or gut issues), the numbers may not reflect what’s actually reaching your cells.

💡 Tip: Consider private testing for homocysteine as a more functional marker of methylation and B vitamin activity. Consider a trial of B-complex support under supervision if symptoms persist.

3. Your gut is unsettled, but tests show no inflammation

You may experience bloating, irregular stools, or food sensitivities that didn’t exist a year ago. Yet standard tests like coeliac screening or inflammatory markers might come back fine.

Why? Because symptoms often show up long before damage does.

Low stomach acid, sluggish bile flow, gut dysbiosis (imbalanced bacteria), or stress-related motility changes can all cause discomfort without raising red flags on routine labs.

💡 Tip: Try slowing meals down, chewing properly, and supporting digestion with bitter foods like rocket, lemon water, or apple cider vinegar before meals. If symptoms persist, stool testing can reveal deeper patterns.

4. Your muscles feel heavy or weak, even with gentle activity

Are you struggling to bounce back from a short walk or workout? That could point to mitochondrial dysfunction, essentially, your cells’ energy factories aren’t running efficiently.

Low levels of nutrients like CoQ10, magnesium, carnitine, and B2 can reduce ATP production, leaving you feeling like your internal battery never fully recharges.

This might not show up on basic tests unless you're specifically looking at thyroid function (especially Free T3), markers of muscle metabolism (CK, LDH), or functional nutrient levels.

💡 Tip: A full thyroid panel (TSH, Free T4, Free T3, and antibodies) is essential for uncovering suboptimal thyroid function that affects muscle recovery and mood.

5. You’re wired but tired, and your body can’t switch off

One of the most common symptoms I see is “tired but wired”, when you feel drained but still buzzed, edgy, or restless. This often points to chronic stress and dysregulated cortisol, even if your cortisol level is within the standard range.

Clues include:

Feeling alert at bedtime
Waking early with a racing mind
Crashing after meals
Feeling shaky or anxious between meals

💡 Tip: Blood pressure swings and energy dips can be tracked at home. A 4-point saliva or urine cortisol test may provide a better picture of how your stress response is functioning throughout the day.

How to get better answers when you're tired all the time

When your bloods come back “fine” but your body doesn’t feel right, the goal isn't to over-test, it’s to ask better questions. Start with what you’re noticing day to day:

Are there patterns to your energy dips?
Do certain foods affect your mood or digestion?
Are you sleeping but still exhausted?
What’s your menstrual cycle or stress level telling you?

From there, targeted testing can fill in the blanks. Tests I often use in clinic include:

Full thyroid panel (including antibodies)
Ferritin, transferrin saturation, and full iron panel
B12, folate, homocysteine
Vitamin D
Blood glucose and insulin
Stool analysis (where gut symptoms persist)

But more than testing, it’s about putting the whole picture together. Your symptoms are a form of data, often more honest than your lab printout.

You’re not being dramatic, your symptoms are real

If you’ve ever been made to feel like you’re “just tired” or “too sensitive,” I want to challenge that. You’re smart, capable, and self-aware and you’re noticing things that matter.

You don’t have to wait for your health to decline further before getting answers. Listening to the small signs now can help prevent bigger issues later.

You deserve more than just reassurance, you deserve clarity.

Are you wanting support?

If you’re tired of feeling tired and want someone to help make sense of your symptoms and blood test results, I’d love to help. The Wellbeing Kickstart is designed for women like you:
✔ Full blood panel
✔ Nutrition and lifestyle review
✔ Personalised, practical plan
✔ Real clarity without overwhelm

Head to Your Wellbeing Kickstart to book.

About Claire

Claire Thomas is a Nutritional Therapist, NLP Practitioner, and Phlebotomist with a background in Children’s Nursing. She specialises in supporting ambitious women who feel exhausted, burnt out, or stuck in survival mode. Through personalised nutrition, mindset coaching, and functional testing, Claire helps her clients increase their energy levels, find clarity, and feel like themselves again. Based in Tiverton, Devon, she works both in-person and online through her clinic, Nourish to Soar

Categories: : energy, fatigue