Explainer: What is metabolic syndrome? | Science News for Students

Explainer: What is metabolic syndrome?

This condition ups a person’s risk of heart disease and diabetes
Mar 4, 2016 — 7:00 am EST
waist measure

Kids and teens who consume too many soft drinks and other sugary foods may gain weight and end up with an “adult” problem known as metabolic syndrome.

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Many people slurp sodas, munch candy and chow down on pizza more often than they should. The body needs the sugar and fat in foods to fuel muscles and other bodily systems. But too much and a person can suffer. In some people, a “couch potato” lifestyle can even lead to life-threatening diseases. These include heart disease and diabetes, a condition that affects how the body processes sugar.

Doctors can check for signs someone is likely to develop these diseases. Enough of those symptoms can signal that someone has developed metabolic syndrome. This person may not have heart disease or diabetes yet, but they will have at least three of the following conditions. Each is a red flag that should alert someone that a lifestyle change is called for.

  • Obesity: When people eat too much and don’t exercise enough, they gain weight. One way doctors measure whether people have a healthy weight is by calculating their body mass index, or BMI. All someone needs to calculate this is have a person’s height and weight. BMI can signal not only whether someone has a weight problem, but also how severe it is. Obesity is the most obvious warning sign in metabolic syndrome. It’s also the one that troubles people most. “Our [overweight] patients get bullied and teased,” notes Melanie Cree-Green. She is a pediatrician at Children’s Hospital Colorado at the University of Colorado Anschutz Medical Campus in Aurora.
  • High blood pressure: Blood carries nutrients through the body. An overweight person has a bigger body, so the heart needs to pump more blood. This extra blood presses hard on the walls of the blood vessels. High blood pressure can lead to heart attacks and other heart problems.
  • Blood sugar problems: The body breaks down food into its building blocks, such as proteins, fats and sugars. A hormone called insulin helps move glucose — a simple sugar also known as blood sugar — from the blood into cells. But in overweight people, insulin often stops doing its job properly. Scientists don’t yet know why. When insulin stops working well, glucose can start to get stuck in the blood. This can lead to a dangerous condition known as insulin resistance. It is a sign the body is at risk of developing type 2 diabetes. That disease can lead to blindness, the loss of digits (such as toes) or limbs (an arm or leg), kidney problems, heart problems — even death. People with diabetes often take shots of insulin to control levels of glucose in their blood.
  • Too much bad fat: A person’s liver normally takes extra sugar and turns it into fats called triglycerides (Try-GLIS-ur-ides). If too many of these fats build up, though, they start to gunk up the inside of the liver. This can lead to a serious condition known as fatty liver disease. A person with this disease may notice dark patches on the skin of the neck or arms, or feel pain on the upper right side of the belly where the liver is located. Blood vessels may get blocked by the bad fats. This can make heart disease more likely.
  • Too little good cholesterol: Cholesterol is a waxy substance similar to fat. Low-density lipoprotein (LDL) cholesterol is the “bad” type because it can build up inside blood vessels. Many fatty foods such as French fries or pizza deliver this cholesterol into the body. The body itself also makes this type of cholesterol. High-density lipoprotein (HDL) cholesterol is the “good” type. It helps mop up the bad stuff, freeing up the blood vessels again. Having a healthy amount of HDL cholesterol can help protect someone from heart attacks and stroke.

Some measures of metabolic syndrome also consider two additional symptoms: blood clots and inflammation, which can be measured through blood tests.

In the past, doctors considered metabolic syndrome to be an “adult” problem. Kids and teens didn’t usually end up with any of the conditions, which can be warning signs of the syndrome. But that is changing. Today, obesity is on the rise among kids. So some are now developing metabolic syndrome and related diseases.

Cree-Green notes that the cure for metabolic syndrome is well understood. Patients must eat healthier food, get more sleep and spend less time sitting around. “I think figuring out how to exercise is the most important thing,” she says.

Power Words

(for more about Power Words, click here)

blood pressure    The force exerted against vessel walls by blood moving through the body. Usually this pressure refers to blood moving specifically through the body’s arteries. That pressure allows blood to circulate to our heads and keeps the fluid moving so that it can deliver oxygen to all tissues. Blood pressure can vary based on physical activity and the body’s position. High blood pressure can put someone at risk for heart attacks or stroke. Low blood pressure may leave people dizzy, or faint, as the pressure becomes too low to supply enough blood to the brain.

blood sugar    The body circulates glucose, a type of simple sugar, in blood to tissues of the body where it is used as a fuel. The body extracts this simple sugar from breakdown of sugars and starches. However, some diseases, most notably diabetes, can allow an unhealthy concentration of this sugar to build up in blood.

body mass index (BMI)    A person’s weight in kilograms divided by the square of his or her height in meters. BMI can be used to evaluate if someone is overweight or obese. However, because BMI does not account for how much muscle or fat a person has, it is not an accurate measure.

cholesterol    A fatty material in animals that forms a part of cell walls. In vertebrate animals, it travels through the blood in little vessels known as lipoproteins. Excessive levels in the blood can signal risks to the blood vessels and heart.

clot    (in medicine) A collection of blood cells (platelets) and chemicals that collect in a small region, stopping the flow of blood.

couch potato    Slang for people who get very little exercise, often because they spend much of their leisure time sitting around, usually watching television.

diabetes    A disease where the body either makes too little of the hormone insulin (known as type 1 disease) or ignores the presence of too much insulin when it is present (known as type 2 diabetes).

fat    A natural oily or greasy substance occurring in animal bodies, especially when deposited as a layer under the skin or around certain organs. Fat’s primary role is as an energy reserve. Fat is also a vital nutrient, though it can be harmful to one’s health if over consumed in excess amounts.

fatty liver disease    A condition that results when too much fat builds up inside the liver. People who are obese or drink too much alcohol risk developing this condition.

glucose   A simple sugar that is an important energy source in living organisms. It is half of the molecule that makes up table sugar (also known as sucrose).

high blood pressure    A serious health condition where blood presses too hard against the walls of blood vessels as it flows. This condition can lead to heart disease, heart attack, kidney failure, stroke and other problems.

hormone    (in zoology and medicine)  A chemical produced in a gland and then carried in the bloodstream to another part of the body. Hormones control many important body activities, such as growth. Hormones act by triggering or regulating chemical reactions in the body. (in botany) A chemical that serves as a signaling compound that tells cells of a plant when and how to develop, or when to grow old and die.

inflammation    The body’s response to cellular injury and obesity; it often involves swelling, redness, heat and pain. It is also an underlying feature responsible for the development and aggravation of many diseases, especially heart disease and diabetes.

insulin    A hormone produced in the pancreas (an organ that is part of the digestive system) that helps the body use glucose as fuel.

insulin resistance    A condition where the body begins to ignore the presence of insulin, a hormone needed to help move energy (sugar) from the blood and into cells where it can fuel their activities. Insulin resistance is an early symptom of people at risk of developing type 2 diabetes.

metabolic syndrome    A health condition made up of any of at least three of the following six problems: obesity, high blood pressure, insulin resistance, high levels of bad fats alongside low good cholesterol, extra blood components that cause inflammation and extra blood components that lead to clots. People with metabolic syndrome have an increased risk of developing diabetes or heart disease.

metabolism    The set of life-sustaining chemical reactions that take place inside cells and bigger structures, such as organs. These reactions enable organisms to grow, reproduce, move and otherwise respond to their environments.

obesity    Extreme overweight. Obesity is associated with a wide range of health problems, including type 2 diabetes and high blood pressure.

overweight    A medical condition where the body has accumulated too much body fat. People are not considered overweight if they weigh more than is normal for their age and height, but that extra weight comes from bone or muscle.

pediatrics    A field of medicine that has to do with children and especially child health. A doctor who works in this field is known as a pediatrician.

proteins    Compounds made from one or more long chains of amino acids. Proteins are an essential part of all living organisms. They form the basis of living cells, muscle and tissues; they also do the work inside of cells. The hemoglobin in blood and the antibodies that attempt to fight infections are among the better-known, stand-alone proteins.Medicines frequently work by latching onto proteins.

stroke    (in biology and medicine) A condition where blood stops flowing to part of the brain or leaks in the brain.

toxin    A poison produced by living organisms, such as germs, bees, spiders, poison ivy and snakes.

triglyceride    The main ingredient of many animal fats and oils. A high level of triglycerides in the blood puts a person at risk for heart disease or stroke.

type 2 diabetes (see also diabetes)    A disease caused by the body’s inability to effectively use insulin, a hormone that helps the body process and use sugars. Unless diabetes is controlled, a person faces the risk of heart disease, coma or death.


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Further Reading

S. Ornes. “Kids with ‘adult’ problems.” Science News for Students. July 2, 2012.

J. Raloff. “Our increasingly not-so-little kids.” Science News. May 21, 2012.

S. Ornes. “Obesity linked to location.” Science News for Students. May 11, 2012.

S. Ornes. “Losing control over sugar.” Science News for Students. March 1, 2012.

S. Ornes. “Fat weights heavy on the brain.” Science News for Students. April 13, 2011.

S. Ornes. “Obesity and the common cold.” Science News for Students. October 5, 2010.

E. Sohn. “Kids now getting ‘adult’ disease: More kids are developing diabetes, and obesity is a major reason why.” Science News for Students. April 24, 2009.

Learn about obesity and try the BMI calculator on the Stanford Health Care website.