A stroke occurs when the supply of blood, and therefore oxygen, to the brain is interrupted, either by the blockage of a blood vessel (called an ischemic stroke) or the rupture of a blood vessel (called a hemorrhagic stroke).

There is growing evidence that a deficit of oxygen to the brain contributes to Alzheimer’s disease and other forms of dementia. It’s also known that tiny cerebral strokes can result in cognition problems.

For these reasons, as well as the acute danger, recognizing that you’re having a stroke and getting help fast is extremely important. The symptoms can include:

• Weakness or numbness on one side of your body

• Drooping on one side of your face

• Difficulty reading or understanding speech

• Slurred speech

• Sudden, extreme headache

• Loss of peripheral vision

• Difficulty walking

One or more of these symptoms should alert you to call 911. The quicker you get to the hospital, the better. But don’t drive yourself.

The steps you take to prevent heart disease support stroke prevention as well:

• Control high blood pressure, which is the greatest stroke risk factor.

• Quit smoking, including e-cigarettes and vaping.

• Control diabetes. Get your blood glucose levels checked regularly; studies find that once diabetes is diagnosed, systemic damage has already occurred.

• Lose weight. Being overweight increases your probability of developing other stroke risk factors, including high blood pressure, high cholesterol, diabetes, and coronary artery disease.

• Limit alcohol intake.