Obese people develop dangerous blood clots -- which can cause heart attacks and strokes - more often than people who are not overweight**.**** Understanding Blood Clotting**
Blood clotting is an important process that helps the body repair injured blood vessels. Mechanisms leave the blood stream to form clots as needed, and platelets form the first cap. These platelets release chemicals to begin the clotting. The protein fibrin is formed and makes a netting to construct the final blood clot.
Blood clotting is a normal process by which the body repairs itself, but if a clot forms that is not needed the consequences can be severe, even deadly.
Blood Clot in Vein (Venous Thrombosis) Venous thrombosis is when blood clots form in a vein. This happens when a person is immobilized and muscles no longer push blood to the heart. The stagnant blood forms small clots along the walls of a vein where the clot can grow until the vein is blocked and blood is prevented from returning to the heart. Large blood clots can break free and travel to the heart or lungs. Here, the clot can cause cardiac arrest (sudden stopping of heart function), stroke, and even death.** Test your knowledge of Post Cardiac Care.**
venous thrombosis - blot clot in the vein
Learn more in HealthCentral's Venous Thrombosis Series.** Research Regarding Blood Clots and Obesity**
Danish researchers found that women who had fat on their hips and men who carried excess weight at the waist were at higher risk for blood clots.
The study was active for ten years and involved some 57,000 subjects who were between the ages of fifty to sixty-four. Six hundred and forty-one blood clots were discovered, and researchers found a positive correlation between blood clots and hip circumference on women and between blood clots and waist size on men. The location of body fat and clotting was gender specific although researchers cannot explain why that is.
A more recent study found a correlation between obesity, blood clots, and height. The research showed that the risk for blood clots was higher for men not only because of weight but also because of height. Body height was not a risk factor for women alone but when combined with weight, the risk factor was greater than for weight alone. Once again, researchers were at a loss to explain the correlation that was found.
Although there is not yet a definitive explanation for the association, it clearly does exist.
When short, non-obese men were compared to tall, obese men, the results showed that tall, obese men had a 5.28 higher rate of clots, and that tall, normal height men had a 2.11 higher risk.** Obese, tall women had a 2.77 higher risk for blood clots** than short, normal weight women.** The Link Between Leptin, Obesity, and Blood Clots** Leptin is a hormone produced by fat cells in the body. Blood clotting begins from an interaction between leptin and the leptin-receptor that is on platelets.
When fat cells release leptin, the appetite is suppressed and body weight can be regulated. As leptin levels rise, the brain sends signals to stop eating.
Leptin levels increase a great deal with every pound of weight that is gained, and obese people have a greater number of fat cells that produce leptin. When leptin reaches extreme levels, obese people become resistant to the signals that are being sent and become more vulnerable to leptin-induced blood clotting.
The association between obesity and blood clots is well known but the cause has remained a mystery. High levels of leptin caused by obesity could explain why.