<s>[INST] What are the causes of stroke? [/INST] Stroke occurs when supply of blood (oxygen supply) is restricted or when a weak blood vessel tears out.

Lifestyle, genetics and other factors have influence on our overall well-being and health. Alterations in healthy lifestyle may increase chances of stroke.
People who live sedentary lifestyle may also suffer stroke
Alcohol and smoking are two demons that gradually kill you. Over consumption of alcohol has hazardous effect on bloodstream. People have reportedly been told to quit smoking as it poses serious threat to health. It not only sows a seed of stroke, but also a bunch of other diseases.
High blood pressure is another cause of stroke. As the name suggests, more pressure is build up against walls of blood vessels that make weak blood vessel to rupture. This causes hemorrhage.
Obesity leads to accumulation of fat deposits in blood stream that can block passages of blood vessels.
Diabetes
Genes too can be blamed for stroke. If any of your family member or close relative has had history of stroke, then you might as well suffer from stroke. So take precautions from beginning. Source: MEDIFEE. Link: https://www.medifee.com/faq/stroke#15. Field: Neurology. Disease: Stroke </s>