What is metabolic syndrome?

Metabolic syndrome is a name given to a number of conditions that often occur together, including obesity, high blood sugar, high blood pressure and high levels of fat in the bloodstream, which can lead to diseases affecting the heart and blood vessels. Multiple studies around the world have shown that this syndrome is common among people with serious mental illness.

Metabolic syndrome is defined as a cluster of risk factors — high blood pressure; low levels of HDL or "good" cholesterol; excessive abdominal fat; and elevated levels of blood sugar, C-reactive protein and triglycerides — that increase a person's chances of developing cardiovascular disease or diabetes later in life. The single biggest risk factor is obesity, and metabolic syndrome usually improves when a person loses weight.

Robert S. Kaufmann, MD
Internal Medicine
If you have the metabolic syndrome, you have an increased risk for heart disease. The syndrome isn't a disease itself but a cluster of risk factors for heart disease and other disorders, such as diabetes. One risk factor alone increases your chance of developing heart disease - having a group of them boosts your risk more. This is true even though some of the factors in the metabolic syndrome may be at levels below those for full-fledged heart disease risk factors. In fact, research indicates that having the metabolic syndrome can raise your chance of developing heart disease and diabetes even if your LDL cholesterol isn't elevated.

Heredity can play a role in whether a person develops the metabolic syndrome, but its underlying causes are abdominal obesity - too large a waist - and physical inactivity. The metabolic syndrome also is related to a condition called "insulin resistance" - which can lead to diabetes.

Insulin is a hormone that helps your body convert glucose (sugar) in the blood into energy. With insulin resistance, the body cannot properly use the insulin it produces. As more and more Americans have become obese in recent years, the problem of metabolic syndrome has become more widespread. Today about one-quarter of all adults in the United States have the metabolic syndrome.

This answer from the National Heart, Lung, and Blood Institute has been reviewed and/or edited by Dr. Robert S. Kaufmann.
Daniel R. Spogen, MD
Family Medicine

The NCEP adult treatment panel 3 defines metabolic syndrome as having three or more of the following criteria:

 1. Abdominal obesity with a waist circumference greater than 40 inches in men, or 35 inches in women.

2. Elevated triglycerides, fasting blood triglycerides equal or greater than 150 mg/dL.

3. Low levels of high-density lipoprotein cholesterol, less than 40 mg/dL for men, and less than 50 mg/dL for women.

4. Elevated blood pressure greater than 130/85, or documented evidence of hypertensive treatment.

5. Evidence of insulin resistance with fasting glucose equal to or greater than 110, although the American Heart Association suggests equal to or greater than 100.

Metabolic syndrome is a name for a group of risk factors that occur together and increase the risk for coronary artery disease, stroke, and type II diabetes. If you have been given a diagnosis of metabolic syndrome (also called Syndrome X), it is because you met some or all of the following criteria: Blood pressure equal to or higher than 130/85 mmHg; Fasting blood sugar (glucose) equal to or higher than 100 mg/dL; Large waist circumference (length around the waist) - Men - 40 inches or more and Women - 35 inches or more; Low HDL cholesterol - Men - under 40 mg/dL and Women - under 50 mg/dL; Triglycerides equal to or higher than 150 mg/dL
Metabolic syndrome is a combination of problems that includes obesity, type 2 diabetes, high blood pressure, abnormal cholesterol levels, and heart disease. It’s thought that from 25 to 33 percent of adults in the US have metabolic syndrome, which greatly increases the risk of heart disease.

According to the American Heart Association and the National Heart, Lung, and Blood Institute, metabolic syndrome is identified as the presence of three or more of the following unhealthy components, including elevated waist circumference (40” or higher for men; 35” or higher for women); elevated triglycerides (150 mg/dL or higher); reduced good (HDL) cholesterol (less than 40 mg/dL for men; less than 50 mg/dL for women); elevated blood pressure (equal to or greater than 130/85 mm Hg); and elevated fasting blood glucose (100 mg/dL or greater). If you have increased blood sugar, abnormal cholesterol, and obesity -- all risk factors for heart disease -- talk to your doctor about a glucose tolerance test. Then follow your doctor’s instructions about diet, exercise and other lifestyle changes you must make to keep metabolic syndrome from damaging the heart, brain and other organs.
Rick Sayegh
Rick Sayegh on behalf of MDLIVE
Internal Medicine
A constellation of symptoms including obesity, high glucose, high cholesterol, and high blood pressure. It is also known as syndrome X.

Metabolic syndrome is the name for a group of risk factors that has been linked to obesity, and that can increase the risk for heart disease, diabetes and stroke (it has also been labeled syndrome X and obesity syndrome). Generally this situation does not have official symptoms, however, patients with metabolic syndrome may also have:

• high blood sugar-when diabetes is present
• high blood pressure
• fatigue
• blurred vision
• headache

Jill A. Grimes, MD
Family Medicine
Metabolic syndrome is passing smoking as the number one risk factor of heart disease in America. Metabolic syndrome occurs when you have three or more of the following:
  • Large waistline (more than 40 inches for men; more than 35 inches for women)
  • High triglycerides, which are a type of fat found in your blood similar to cholesterol (more than 150 mg/dL+M98)
  • Low HDL, the good cholesterol (less than 40 mg/dL for men; less than 50 mg/dL for women)
  • High blood pressure (more than 130 top number or more than 85 bottom number)
  • High fasting blood sugar (more than 100 mg/dL)
  • Also note that if you are on medications for triglycerides, cholesterol, high blood pressure or diabetes, it counts as one of the three conditions, regardless of your current numbers.

Dr. Vonda Wright, MD
Orthopedic Surgery
When you carry your weight around your waistline you are more likely to develop "metabolic syndrome." This is a dangerous condition where your waist measures greater than 36 inches if you are a man, and greater than 40 inches if you are a woman and you have two of the following four cardiac risk factors: high triglycerides (blood fat), high blood sugar, high blood pressure, and low HDL (the good cholesterol). Metabolic syndrome increases the likelihood of developing type II diabetes by more than 500 percent, increases your chances of having a heart attack by 300 percent, and dying of a heart attack by 200 percent.

Fitness After 40: How to Stay Strong at Any Age
Dawn Marcus
Patients with metabolic syndrome have abnormalities in their blood levels of fats, cholesterol, and glucose. They typically have high blood pressure and are overweight. Metabolic syndrome increases your risk for developing diabetes and heart disease. Being inactive and overweight are major risk factors for developing metabolic syndrome. Metabolic syndrome affects about one in every three adults. And what’s the most important way to both prevent and treat metabolic syndrome? Exercising and losing weight.
In addition to a host of other conditions and diseases, being overweight or obese can also lead to metabolic syndrome, a disorder that often includes high blood pressure, high cholesterol and high blood sugar.

Metabolic syndrome is not a single disease but a cluster of health problems. Experts say the syndrome may be caused by a combination of genes and lifestyle factors, including overeating and lack of physical activity.
A complex health problem, metabolic syndrome blends three or more of the following factors: a large waistline, high blood pressure, high triglycerides, low high-density lipoprotein (HDL) cholesterol, and difficulty regulating blood sugar. Research has shown metabolic syndrome significantly raises risk for stroke, heart disease, and diabetes. A growing body of evidence suggests that it raises risk for Alzheimer's disease, too.
Michael T. Murray, ND
Naturopathic Medicine

Many people with impaired glucose tolerance fulfill other criteria of what is known as the metabolic syndrome. This condition, originally referred to as "syndrome X" by Stanford University endocrinologist Gerald Reaven, M.D., refers to a cluster of metabolic risk factors that includes:

  • Central obesity (excessive fat tissue in and around the abdomen) as demonstrated by a greater waist-to-hip ratio
  • Low levels of HDL cholesterol:
  • Men: Less than 40 mg/dl
  • Women: Less than 50 mg/dl
  • Fasting blood triglycerides greater than or equal to 150mg/dl
  • Elevated blood pressure (130/85 mmHg or higher)
  • Insulin resistance (the body can't properly use insulin or blood glucose), as demonstrated by the presence of pre-diabetes (glucose levels between 101 and 125 mg/dl)

The metabolic syndrome is a serious health issue, because people who have it are at increased risk for coronary artery disease, other diseases related to plaque buildup in artery walls (e.g., stroke and peripheral vascular disease), and type 2 diabetes. The presence of four or more of the above criteria is associated with a two and a half times greater risk of having a heart attack or stroke and a nearly twenty-five times greater risk of developing diabetes.

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If you have three components of the deadly quintet of abdominal obesity, high blood pressure, glucose intolerance (or prediabetes), high triglycerides and low good (HDL) cholesterol, you will have a markedly increased risk of cardiovascular disease. This condition is called metabolic syndrome.
Also called syndrome X, metabolic syndrome is really a cluster of factors that together have been shown to coincide with heart risk. These factors are a large waist, high triglyceride levels, low high- density lipoprotein (HDL), high blood pressure, and high fasting blood glucose. Weight loss, exercise, and a heart-healthy diet low in sugar and refined carbohydrates are often prescribed to help treat metabolic syndrome.
Agueda Hernandez, MD
Family Medicine
Metabolic syndrome does not refer to a single condition but to a group of risk factors -- such as high blood pressure, high blood sugar, undesirable cholesterol levels, and a large waist size. 

Individually, these risk factors post a risk to your health. But when they're combined, they can add up to much more serious problems.

The risk factors in some combination can double your risk for cardiovascular disease, which can lead to heart attacks and strokes. They increase your risk of diabetes by five times.

Metabolic syndrome is becoming more common and better understood. And more people are becoming aware that these risk factors can be controlled and reduced through diet, exercise and medication if needed.

According to the American Heart Association, 47 million Americans have metabolic syndrome.

Metabolic syndrome has varying definitions, depending on which society's guidelines you look at. Whether you are a man or woman, the definition is also going to vary, and your ethnicity also factors into that a bit. Nevertheless, you would fit the definition for having metabolic syndrome if you have an increased waist circumference with a combination of at least two of the four following medical problems: elevated triglycerides, a low HDL (the good cholesterol), high blood pressure (high systolic blood pressure or high diastolic blood pressure) and an elevated blood sugar level.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.