When your left eye twitches, it usually means an involuntary spasm or fluttering of the eyelid muscles, medically called eyelid myokymia. This is typically harmless and often caused by factors like stress, fatigue, caffeine intake, or dry eyes. Most eye twitches resolve on their own and are temporary. Occasional left eye twitching is not a sign of serious health issues and is commonly linked to lifestyle-related triggers. However, if the twitching persists for weeks, becomes severe, or spreads to other facial muscles, it could indicate a more serious condition requiring medical attention. In summary, left eye twitching generally means a minor muscle spasm often triggered by fatigue, stress, or caffeine, but persistent or worsening twitching should be evaluated by a professional.