Cognitive Symptom

Brain Fog — Causes, Related Tests & What Helps

Why you feel mentally foggy or unfocused, the underlying causes worth ruling out, and what helps.

What Is Brain Fog?

Brain fog isn't a medical diagnosis itself — it's a cluster of symptoms including poor concentration, forgetfulness, and a feeling of mental fatigue or confusion. It can stem from many underlying causes.

Common Causes

Tests Your Doctor May Order

TestPurpose
TSHChecks thyroid function
Vitamin B12 & FolateCommon deficiencies linked to cognitive symptoms
Vitamin DLow levels are linked to fatigue and poor concentration
CBCChecks for anaemia
Fasting Glucose / HbA1cRules out blood sugar imbalance
CRPScreens for underlying inflammation

What Helps

Important: Persistent brain fog deserves a medical work-up to rule out treatable causes like thyroid disease or vitamin deficiency.