Brain Fog

Difficulty concentrating, forgetfulness, or a persistent mental fog can be linked to underlying nutrient and hormone levels. Thyroid function, vitamin B12, and ferritin all play a role in cognitive function, and are simple to check with finger-prick blood tests.

Order your tests online, take a small sample at home, and post it to our UK lab using the prepaid envelope provided. Results are typically ready within days, with clear reference ranges to discuss with your GP.

Brain fog has many possible causes, including sleep, stress, and other health conditions. These tests are designed to help identify physical contributors alongside your symptoms, not to diagnose the underlying cause on their own.

Browse our brain fog blood tests below, or explore individual tests for Thyroid Function, Vitamin B12, and Ferritin.