Tired? Bloated? Foggy? It’s Probably Not Just Stress

You’re exhausted no matter how much you sleep. You can’t focus. Your gut feels unpredictable. And yet, when you raise it with your GP, you hear the same phrase again:

“It’s probably just stress.”

But what if it’s not?

While stress can trigger a wide range of physical symptoms, vague complaints like fatigue, brain fog, and bloating are often tied to underlying imbalances in key biomarkers—markers that are routinely overlooked unless you test for them intentionally.

At TrueVitals, we believe in investigating what’s behind the symptoms. Below, we break down some of the most common culprits and how blood testing can reveal what’s really going on.

1. Fatigue That Doesn’t Go Away? Check Your Iron, B12, and Thyroid

Chronic tiredness is one of the most common complaints in general practice—and also one of the most under-explored.

Key biomarkers to test:

• Ferritin (Iron stores): Low-normal ferritin (<50 ng/mL) is strongly associated with fatigue, especially in women¹.
• Vitamin B12: Levels below 300 pmol/L can impair energy production and neurological function, even if they’re technically within NHS reference ranges².
• TSH, T3, T4 (Thyroid hormones): Subclinical hypothyroidism can cause profound fatigue long before it meets diagnostic thresholds³.

Feeling “fine on paper” doesn’t mean your body is functioning at its best. Small deficits, across multiple systems, can compound into persistent exhaustion.

2. Bloating and Digestive Upset? Look at Inflammation and Nutrient Absorption

Digestive issues are often dismissed as lifestyle-related—but can stem from measurable dysfunctions.

Biomarkers that may reveal insight:

• CRP (C-reactive protein): Low-grade systemic inflammation can affect gut health and immune signalling.
• Iron, Folate, and B12: Poor absorption due to undiagnosed GI issues (like SIBO, low stomach acid, or IBS) often presents with deficiencies.
• Vitamin D: Deficiency has been linked to both gut permeability and microbiome disruption⁴.

Testing these markers gives you a clearer picture of whether your digestive issues are rooted in biology—not just food or stress.

3. Brain Fog? Cortisol, Inflammation and Glucose Control May Be the Cause

Brain fog isn't just “in your head”—it’s often linked to hormonal or metabolic disruption.

Check these markers:

• Cortisol (morning): Chronic stress can dysregulate the HPA axis, causing cortisol to spike or crash at the wrong times⁵.
• HbA1c & Glucose: Blood sugar fluctuations (even in non-diabetics) can reduce cognitive clarity and focus.
• hs-CRP: Inflammation is strongly associated with cognitive dysfunction and brain fog, especially in younger adults⁶.

If you feel like you’re thinking through syrup or struggling to find words, your blood might explain more than you realise.

4. Why Guess, When You Can Test?

Symptoms like tiredness, bloating, and fogginess are frustrating because they’re non-specific. But they’re often early warnings—the body’s way of asking for help long before a condition becomes serious.

Conventional healthcare waits for disease. TrueVitals looks for dysfunction.

By testing up to 80+ biomarkers in a single screen and interpreting your results against optimal, not just clinical ranges, we help uncover:

• Nutritional deficiencies
• Hormonal imbalances
• Inflammatory activity
• Metabolic inefficiencies

All of which can be adjusted, optimised, and retested—so you can actually feel better, not just get told you're fine.

5. Take Control Before It Escalates

When vague symptoms are ignored, they don’t usually resolve—they adapt. You learn to function at 70%. You rely on caffeine. You get used to feeling foggy.

But there’s a smarter way forward:

• Take our lifestyle quiz to find the right panel for your goals.
• Test your key biomarkers with expert lab analysis.
• Get a personalised report explaining what’s affecting your body and what you can do about it.

You deserve more than “probably just stress.” You deserve answers.

References

1. Tolkien, Z. et al. (2015). "Ferrous sulfate supplementation in iron-deficiency anaemia: A systematic review." BMJ Open.
2. O'Leary, F., Samman, S. (2010). "Vitamin B12 in health and disease." Nutrients.
3. NICE NG145. "Thyroid disease: assessment and management." (2019)
4. Cantorna, M. T. (2011). "Vitamin D and the immune system: an overview." Proceedings of the Nutrition Society.
5. Tsigos, C., Chrousos, G. P. (2002). "Hypothalamic–pituitary–adrenal axis, neuroendocrine factors and stress." J Psychosom Res.
6. Marsland, A. L. et al. (2006). "Systemic inflammation and cognitive performance." Psychosomatic Medicine.

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