How Weight Affects DVT

Obesity has more than doubled since 1980 worldwide. The number of deep-vein clots is rising right along with that.

Doctors aren't yet sure exactly why, but people who have a body mass index of at least 30 are more likely than people of normal weight to get a blood clot deep in a vein, called deep vein thrombosis, or DVT.

What Causes It?

People who are obese tend to have a less active lifestyle. Being idle makes your blood flow sluggish, and this makes clots more likely.

Extra fat around your belly will also stop blood from moving easily through the deep veins.

Obesity changes the chemical makeup of blood, and it leads to inflammation. Both make your blood more prone to clotting.

And obesity puts you at risk for diabetes, which boosts your chances for getting DVT, too.

What You Can Do

Studies show that losing weight can change your blood chemistry and lower your risks. Overweight and obese adults who did moderately intense aerobic exercise improved their blood health, even if they didn't lose weight.

Unfortunately, it doesn't look like you can lower the risk of a second DVT by losing weight after you've had one.

A lot of fish with omega-3 fatty acids in your diet may help protect your blood against abnormal clotting. Avoid high-carb diets -- they can make your blood more likely to clot.

Your doctor can and should help you get from obese to a healthy weight.

WebMD Medical Reference Reviewed by Nayana Ambardekar, MD on January 21, 2020



Allman-Farinelli, M. Seminars in Thrombosis and Hemostasis, November 2011.

CDC: "Deep Vein Thrombosis [DVT] / Pulmonary Embolism [PE] -- Blood Clot Forming in a Vein, Facts."

Sam Schulman, MD, director, Clinical Thromboembolism Program, Hamilton Health Sciences, Hamilton General Hospital, Hamilton, Ontario.

Natalie Evans, MD, vascular medicine specialist, Miller Family Heart and Vascular Institute Cleveland Clinic, Cleveland, OH.

Marc Passman, MD, director, Vein Program, University of Alabama at Birmingham.

© 2020 WebMD, LLC. All rights reserved.