Introduction to Metabolic Syndrome

About 30 percent of adults in the U.S. and 25 percent of adults around the world have metabolic syndrome, also known as Syndrome X. What is this medical condition, and how is it related to obesity?
Introduction to Metabolic Syndrome

Metabolic Syndrome, sometimes called Insulin Resistance Syndrome or Syndrome X, is a medical condition characterized by a cluster of health-related findings. People with metabolic syndrome are more likely to have (or develop) a variety of diseases, including atherosclerotic heart disease, high blood pressure, type 2 diabetes, polycystic ovary syndrome and blood clots.1 Metabolic syndrome has also been linked with gout and nonalcoholic fatty liver disease.2 Obesity is the primary cause.

Risk Factors
According to the National Institutes of Health (NIH) and International Diabetes Federation (IDF) diagnostic criteria, metabolic syndrome is identified when three of the five risk factors are present:

  1. Abdominal obesity, defined as a waist circumference of more than 40 inches in men or 35 inches in women.
  2. Blood triglyceride levels that are 150 milligrams per deciliter (150 mg/dL) or higher.
  3. High Density Lipoprotein (HDL) Cholesterol levels of less than 40 mg/dL in men or 50 mg/dL in women.
  4. Blood pressure that is 130/85 mmHg (millimeters of Mercury) or higher.
  5. Fasting blood glucose level of 100-110 mg/dL or higher.3,4

Metabolic syndrome is common in the United States and throughout the world. Diagnostic factors that are behind the high prevalence include the presence of high blood pressure, abdominal obesity and elevated blood triglyceride levels.5

Metabolic syndrome is also found in adolescents. In the U.S., it is estimated that 6-7% of adolescents fit the diagnostic criteria for metabolic syndrome. The syndrome is found significantly more often in boys than girls.6

Link to Obesity
As weight increases, so does the likelihood of having metabolic syndrome. In a study done in Italy, metabolic syndrome was found in 53% of the people who were obese. In this group, the likelihood of having metabolic syndrome increased with age and was less likely to occur among those who followed a structured exercise regimen.7

Treatment for Metabolic Syndrome
Medical monitoring by a health care professional is important for people with metabolic syndrome. Lifestyle change is the primary treatment for this condition. All five components of metabolic syndrome are improved with weight loss and exercise.

For those with an elevated fasting glucose level, there is good evidence that eating a diet rich in fiber and low in saturated fat, along with regular physical activity and weight loss, is helpful in preventing the development of diabetes. Those who exercise the most gain the most benefit. In addition, nonalcoholic fatty liver disease and polycystic ovary syndrome improve with lifestyle modification.8

The Weight Watchers Approach
The lifestyle changes recommended to treat metabolic syndrome are built into the Weight Watchers approach. The food plan encourages making food choices that are rich in fiber and low in saturated fat. The PointsPlus Activity System provides a way to make regular exercise a part of daily life.

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This content is reviewed regularly. Last updated June 10, 2011.


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1Smith DO, LeRoith D. Insulin resistance syndrome, pre-diabetes, and the prevention of type 2 diabetes mellitus. Clin Cornerstone. 2004;6(2):7-6.

2Daskalopoulou SS, Mikhailidis DP, Elisaf M. Prevention and treatment of the metabolic syndrome. Angiology. 2004 Nov-Dec;55(6):589-612.

3National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Circulation. 2002 Dec 17;106(25):3143-421.

4The International Diabetes Federation consensus worldwide definition of the Metabolic syndrome. 2006.

5Mozumdar A, Liguori G. Persistent increase of prevalence of metabolic syndrome among U.S. adults: NHANES III to NHANES 1999-2006. Diabetes Care. 2011 Jan;34(1):216-9.

6Duncan GE, Li SM, Zhou XH. Prevalence and trends of a metabolic syndrome phenotype among U.S. Adolescents, 1999-2000. Diabetes Care. 2004 Oct;27(10):2438-43.

7Marchesini G, Melchionda N, Apolone G, Cuzzolaro M, Mannucci E, Corica F, Grossi E; QUOVADIS Study Group. The metabolic syndrome in treatment-seeking obese persons. Metabolism. 2004 Apr;53(4):435-40..

8Wagh A, Stone NJ. Treatment of metabolic syndrome. Expert Rev Cardiovasc Ther. 2004 Mar;2(2):213-28.