Research published in the International Journal of Cardiology demonstrates a strong relationship between elevated blood viscosity and the severity of metabolic syndrome. 

Metabolic syndrome affects more than 45 million people in the U.S. The disease is a cluster of conditions– increased blood pressure, elevated insulin levels, excess body fat around the waist, elevated triglycerides, and low HDL levels – that together sharply increase the risk of type-II diabetes and cardiovascular diseases. Metabolic syndrome is defined as having three or more of these conditions, according to National Cholesterol Education Program guidelines. 

Cardiologist Lei Zhang studied 1,400 people aged 35 to 59 and placed them into one of four groups based upon their systolic blood viscosity levels. Subjects with metabolic syndrome were twice as likely to be in the highest viscosity group as the lowest. Subjects with all four of the metabolic syndrome components were almost five times as likely to be in the highest blood viscosity group as the lowest. 

Blood Viscosity (BV) Quartiles: 

First quartile (BV < 43) 

Second quartile (43 < BV < 47) 

Third quartile (47 < BV < 52) 

Fourth quartile (BV > 52) 

The study authors stated that viscosity “is strongly related to the severity of the metabolic syndrome and that the hemorheological parameters could be added to the indicators of the metabolic syndrome” as well as targeted to reduce the risk of cardiovascular diseases.

Blood viscosity has been previously associated with many cardiac risk factors including high blood pressure, LDL cholesterol, and obesity. A study published in the International Journal of Obesity noted obese patients (BMI > 28) had on average 15% higher diastolic blood viscosity than non-obese healthy controls. 


1. L. Zhang, et al. Blood rheological properties are strongly related to metabolic syndrome in middle-aged Chinese. International Journal of Cardiology, 2006; 112(2):229-233. 

2. E. Rillaerts, et al. Blood Viscosity in Human Obesity: Relation to Glucose Tolerance and Insulin Status. International Journal of Obesity, 1989; 13(6):739-745.