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Bloodletting Makes Comeback for Metabolic Syndrome

A small study shows that a little blood loss might improve cardiovascular health for obese people with metabolic syndrome. Katherine Harmon reports

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Leeches and lances might seem like prescriptions from the past. But bloodletting might be back in vogue. A small study shows that losing a little blood might improve cardiovascular health for obese people who also have what’s called metabolic syndrome.

The study tracked 33 patients with metabolic syndrome—defined by the presence of some of an assortment of conditions, such as high cholesterol, hypertension and insulin resistance. Researchers took 300 milliliters of blood from the patients, a little less than the one pint standard donation, with a repeat treatment a month later.

After six weeks, treated adults had lower blood pressure than the control group. Glucose levels also decreased, which suggests limited blood removal might improve metabolic health. The findings are in the journal BMC Medicine. [Khosrow Houschyar et al., "Effects of phlebotomy-induced reduction of body iron stores on metabolic syndrome: results from a randomized clinical trial"]


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The researchers think that the blood loss reduces iron levels. And excess iron in the blood has been tied to many metabolic syndrome ailments.

The FDA has okayed leeches for some procedures. Which could lead patients to thank their doctors for a treatment that sucks.

—Katherine Harmon

[The above text is an exact transcript of this podcast.]

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