The Vein Signal

Shining a light on the circulatory blindspot — venous disease, microclots, lymph & vascular damage — so you can fight for a better new "normal," one they said you couldn’t have.

Brain Fog

Brain Fog — When It’s Not Just in Your Head.

Some days, you just can’t focus. Your brain feels wrapped in cotton, your attention wanders, you can’t find the words. The term brain fog may sound soft, but to those of us experiencing it — especially in the context of long-COVID, vascular injury (including varicose veins, lymphedema, and peripheral artery disease), chronic inflammation, or hormone imbalance — it can be deeply distressing and disabling.

What Is Brain Fog, Really?

Brain fog isn’t a medical diagnosis, but it’s a signal. And like all signals, it’s telling us something about the state of our internal systems. It’s a form of cognitive dysfunction often described as:

  • Short-term memory lapses
  • Mental fatigue
  • Trouble concentrating or focusing
  • Slowed thinking or word recall
  • Feeling disoriented or detached

These conditions are often overlooked because the term “vascular” is so often associated with the heart alone. But perfusion issues, meaning how well blood is delivering nutrients thru tissue, begin in the legs, the lymph, or the brain — and perfusion issues impacting the brain are significant: Many of us feel a specific kind of friction or fizzle in our thinking, like we’re trying to work through molasses — or feel as if we need a special jolt. It’s as if blood, oxygen, and clarity just aren’t getting to the right places fast enough.

The Vascular Connection

But brain fog needs to be evaluated through a systems lens — and vascular health is foundational.

The brain demands a constant, rich supply of oxygen and nutrients. If blood flow is compromised — through microclots, endothelial damage, autonomic nervous system dysfunction (often called dysautonomia), or chronic venous insufficiency (CVI, the clinical term for varicose veins and related vein issues) — mental performance suffers. This isn’t speculative. We now know that impaired perfusion, meaning blood flow through tissue, can impact not just muscles and organs, but memory, processing speed, and emotional regulation.

Cognitive impairment is frequently observed in patients with chronic heart failure and other vascular diseases, suggesting that reduced cerebral perfusion is a key mechanism of dysfunction.

— Journal of Cerebral Blood Flow & Metabolism

COVID-related spike protein exposure, including from vaccines, has been linked to microvascular dysfunction. For some, this presents as sudden-onset brain fog. For others, it’s a progressive decline in cognition that doesn’t reverse with rest.

Glymphatic Dysfunction and Drainage Issues

When blood can’t reach the brain efficiently, waste can’t drain properly either. Enter the glymphatic system — a newly recognized brain-cleaning mechanism that operates mostly during sleep. It clears cellular, metabolic waste through fluid exchange between cerebrospinal fluid and interstitial fluid.

Poor sleep, chronic inflammation, intracranial hypertension, and microvascular injury can all impair glymphatic flow — leading to toxin buildup in brain tissue.

This might explain why:

  • Brain fog worsens after poor sleep.
  • You feel foggy during a flare-up of systemic symptoms – even a head cold or the flu.
  • Certain head positions or postures during sleep can make it worse.

When Fog Meets Hormones

Estradiol, testosterone, progesterone, thyroid hormones, and even melatonin all impact cognition, perfusion, and neuroprotection. When these are low or dysregulated, the brain may receive less oxygen, fewer protective nutrients, and diminished anti-inflammatory signals.

The result? Brain fog with emotional volatility, spatial disorientation, or slowed reaction time — even in people with otherwise normal labs.

It’s Not All in Your Head

Brain fog is often brushed off — especially for women, the elderly, and people with chronic illness — as anxiety, aging, or “just stress.”

But if you:

  • Frequently lose your train of thought mid-sentence (beyond just the occasional lapse)
  • Feel like you’re moving through static
  • Experience light sensitivity or word-finding issues
  • Notice changes in how you handle pressure or time

…you’re not imagining it. And you’re not alone. Brain fog is real. It’s traceable. And often, it’s reversible — but only when we acknowledge its vascular and systemic underpinnings.

Suggestions and Next Steps

If you’re experiencing persistent brain fog — especially alongside symptoms like leg swelling, varicose veins, or unexplained fatigue — you may benefit from exploring these related topics — including how micro vascular dysfunction might be blocking your recovery:

Basic Support Strategies

These suggestions are not a substitute for medical advice but may offer gentle support while you explore the root causes of your symptoms:

  • Prioritize sleep hygiene to support glymphatic drainage: No blue light for at least an hour before bedtime, sleep in a dark bedroom, and optimally sleep on your left-side. Note that lying on your right side is still more optimal than sleeping on your back or your stomach for glymphatic support.
  • Consider leg elevation and compression when you’re not sleeping if you have signs of varicose veins, heavy legs, or venous disease.
  • Support nitric oxide production with gentle movement, hydration, and flavonoid-rich foods (like cocoa or pomegranate) or high-flavanol supplements.
  • Avoid alcohol or sedatives in the evening — they reduce restorative sleep phases.
  • Avoid long periods of sitting or standing without movement; if you work at a computer, you need to work movement into the mix.

At The Vein Signal, we know how frustrating it is to feel like your brain is slipping — especially when the medical system doesn’t acknowledge that brain fog is real. That’s why we’re building tools to help people connect symptoms to deeper root causes.

This article is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider regarding any medical concerns or before beginning any new protocol.

References

Cramer H. et al. (2023). Sex Hormones and Cognitive Function: Emerging Insights. Frontiers in Aging Neuroscience. https://doi.org/10.3389/fnagi.2023.1190885

Benveniste H. et al. (2019). The Glymphatic System and Waste Clearance with Brain Aging: A Review. Gerontology. 65(2): 106–119. https://doi.org/10.1159/000490349

Heneka MT. et al. (2020). Neuroinflammation in Alzheimer’s Disease. The Lancet Neurology. 19(8): 711–726. https://doi.org/10.1016/S1474-4422(20)30226-9

Reynolds JL. et al. (2022). The Impact of Long COVID on Cognitive Function: A Review. Nature Reviews Neurology. https://doi.org/10.1038/s41582-022-00735-x

Wostyn P. (2021). The Glymphatic Hypothesis of Brain Fog in Long COVID. Med Hypotheses. 152:110612. https://doi.org/10.1016/j.mehy.2021.110612

Iadecola C. (2017). The Neurovascular Unit Coming of Age: A Journey through Neurovascular Coupling in Health and Disease. Neuron. 96(1):17–42. https://doi.org/10.1016/j.neuron.2017.07.030

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Disclaimer: The Vein Signal provides educational content only. It’s not a substitute for medical advice. Always consult your healthcare provider before making changes to your health regimen.