Table of Contents I. Why Do Blood Clots Occur? II. Maintaining a Healthy Weight III. Avoiding Sedentary Periods IV. Staying Active V. Eating a Healthy Diet VI. Avoid Smoking Why Do Blood Clots Occur? Blood clots are very common, affecting around 900,000 Americans yearly. Your body’s clotting factor functions to stop excessive bleeding when there is an open wound. If plaque buildup causes a blood vessel to rupture, an internal blood clot may occur and lead to a medical emergency.