What's the biggest risk factor for stroke?

High blood pressure (or hypertension) is the biggest risk factor for stroke (by far). It is, of course, controllable and can be lowered safely into the normal range. Other risk factors for stroke that are equally controllable are (in order of their importance):

That is all that we'll say here about factors #1 through #3. Now a few things about hypertension, the top contributor to stroke.

The risk of stroke varies directly with the blood pressure. As the blood pressure rises, so does the risk of stroke. The role of hypertension as a risk factor for stroke is further magnified by how common it is. Close to one in three adults in America has hypertension.

Sex does not mitigate the danger of hypertension. Women with high blood pressure are as likely as men to suffer a stroke.

Age does not ease the effect of high blood pressure. At age 60 hypertension is a risk factor for stroke just as it was at age 40.

You (and everyone else) should have a regular blood pressure check. If your blood pressure is not taken, how can you know if it is OK? or too high?

Reducing hypertension cuts the chance of a stroke significantly. Since the risk of a stroke varies directly with the blood pressure, as the blood pressure goes down, so does the risk of stroke.

High blood pressure can often be brought into the normal range by natural means - by eating a healthier diet, by exercising properly, and by attaining and maintaining proper weight.