A brain map shows how your brain is working. It can’t show why on its own. Some of the most common and most treatable contributors to poor memory, focus and energy start elsewhere in the body, and a blood test is the simplest way to find them.
Routine tests for brain health
Our standard brain health blood tests check for general metabolic issues, vitamin deficiencies and problems with organ function that can affect how you think:
- Vitamin B12 and folate. Deficiencies can cause confusion, memory loss and fatigue.
- Thyroid function (TSH, T3, T4). An underactive or overactive thyroid can affect brain metabolism and alertness.
- HbA1c and fasting glucose. These measure blood sugar to check for diabetes, which affects blood flow and brain health.
- Liver and kidney function. These confirm that metabolic waste is being filtered properly, so it isn’t affecting mental clarity.
- Inflammatory markers (CRP). These check for chronic inflammation in the body, which can influence cognitive decline over time.
An abnormal result here doesn’t explain everything. But when it does turn up, it is often something that can be addressed directly, and it changes how a brain map should be read.
Advanced biomarkers, where appropriate
These are not standard tests, and we only recommend them where they are clinically appropriate. Blood testing can now measure specific proteins linked to neurodegeneration:
- Amyloid-beta and tau proteins can detect abnormal protein build-up associated with Alzheimer’s disease in people with symptoms.
- Neurofilament light chain (NfL) is a structural protein released when nerve cells are damaged, so raised levels can indicate active nerve cell damage and neurodegeneration.
These markers need careful interpretation. NfL, for example, isn’t specific to one condition, and levels are affected by factors such as age and kidney function. A single result is read in the context of your history, your symptoms and your other findings, never on its own.
Why put them together?
Suppose a brain map shows the slowed, foggy pattern often seen with mental fatigue. If your B12 is also low, or your thyroid is underactive, that changes what you should do first. Looking at the brain and the body together means the plan addresses the cause, not just the pattern.
Sources
- Barro C, Chitnis T, Weiner HL (2020). Blood neurofilament light: a critical review of its application to neurologic disease. Annals of Clinical and Translational Neurology, 7(12), 2508–2523. View source
This article is general information, not medical advice. It doesn’t replace the guidance of your own doctor. If you have sudden or severe symptoms, contact your GP, NHS 111 or A&E.
