Metabolic syndrome may undermine the brains of teens as well as their bodies, a small study suggests. Metabolic syndrome means having at least 3 of 5 unhealthy conditions. The conditions are high blood pressure, large waist, high triglycerides (a blood fat), low HDL ("good cholesterol") and insulin resistance. Metabolic syndrome increases the risk of diabetes and heart disease. The new study included 111 teenagers. Of this group, 49 had metabolic syndrome and 62 did not. Both groups were a similar mix of ages, family income, school grade, gender and ethnicity. Everyone took tests of ability in subjects such as spelling and math. They also took tests of brain function, such as memory and attention. Teens with metabolic syndrome had about 10% lower scores on the subject tests. They also scored lower on attention, but not memory. Each teen also had an MRI brain scan. Teens with metabolic syndrome tended to have a 10% smaller hippocampus. This part of the brain helps to form memories. These teens also had less "white matter," which carries information in the brain and to the spinal cord. The journal Pediatrics published the study online. HealthDay News wrote about it September 3.

By Henry H. Bernstein, D.O.
Harvard Medical School

What Is the Doctor's Reaction?

The facts are staggering.

• Being overweight or obese is a major health problem for families today.
• Childhood obesity has more than tripled in the last 30 years.
• More than 1 child or teen out of 3 is overweight or obese.
• Obese youth are more likely to have conditions that increase their risk of heart disease, such as high cholesterol or high blood pressure.
• Obese youth are at higher risk for strokes and type 2 diabetes as adults.

Childhood obesity also is linked with a condition called metabolic syndrome. This is not a disease itself. Metabolic syndrome describes a group of factors that increase the risk of developing heart disease and type 2 diabetes.

It is also known that adults with metabolic syndrome can have related effects on the brain. In a new study, researchers looked at whether these brain problems are also seen in teens with metabolic syndrome. The journal Pediatrics published the study this week.

Researchers compared 49 teens with metabolic syndrome to 62 teens without it. A child was diagnosed as having metabolic syndrome if he or she had at least 3 of the following:

• Excessive belly fat
• High blood pressure (hypertension)
• Low levels of HDL or "good cholesterol"
• High levels of triglycerides (a type of fat found in the blood)
• Insulin resistance (when the body's cells don't respond normally to insulin, the hormone that helps to move sugar from the bloodstream into cells)

The researchers found that teens with metabolic syndrome scored significantly lower than their peers without it on tests of:

• Spelling
• Arithmetic
• Attention
• Mental flexibility

They also tended to have lower overall intelligence than teens without metabolic syndrome. Teens with metabolic syndrome did not differ from their peers on memory tests. They also had similar psychomotor efficiency. This is the ability to respond quickly and appropriately to an event.

Teens with metabolic syndrome also had these brain abnormalities:

• Smaller hippocampus -- The hippocampus is a part of the brain that is very important in forming memories.
• Increased brain cerebrospinal fluid -- Cerebrospinal fluid is a clear liquid that acts as a cushion and protects the brain from injury.
• Lower quality of white matter -- White matter is brain tissue that carries information between the nerve cells in the brain and spinal cord.

These brain abnormalities seen with metabolic syndrome suggest that childhood obesity should be treated early and completely. Brain function may even need to be formally measured when considering the treatment of childhood obesity.

What Changes Can I Make Now?

A diet that is high in calories and low in good nutrients puts a child at risk for metabolic syndrome. Not getting enough (or any) exercise also increases a child's risk.

At home, you can help to prevent metabolic syndrome by living a healthy, active family lifestyle. Here's what you can do:

• Encourage physical activity. Parents play a key role in helping their children become more physically active. Encourage playtime! Make physical activity fun. Remember, parents are role models. If you are physically active, your child will follow your example. The American Academy of Pediatrics (AAP) recommends at least one hour of physical activity a day for children.



• Form healthy eating habits. Create a home where healthy choices are on hand and encouraged! Cook healthy meals together. The AAP recommends:
  
  • Regularly eating meals together as a family
  • Preparing foods at home as a family
  • Eating breakfast every day
  • Eating low-fat dairy products such as yogurt, milk and cheese
  • Limiting fast food, take-out food and restaurant meals
  • Eating a diet rich in calcium
  • Eating a high-fiber diet


• Limit screen time. Children spend too much time watching TV, using the computer or playing video games. The more time your child spends in front of a screen, the less time he is outside being active. The AAP recommends limiting screen time to no more than two hours per day.



• Avoid sugary drinks. Sugar-sweetened beverages are the largest source of added sugars in children's diets. Such drinks add many calories, but have little (or no) nutritional value. Instead, encourage your child who is 2 years of age or older to drink water and low-fat milk. Limited amounts of 100% fruit juices are OK too. The AAP recommends no sugary drinks for children.

What Can I Expect Looking to the Future?

Researchers will look at whether the brain concerns linked with metabolic syndrome can be reversed if the child loses a lot of weight.

You also can expect to hear more from your child's doctor about the importance of living a healthy, active lifestyle. This means good eating habits and lots of regular exercise.

It is important for all families to take up healthy habits. This should begin when children are young.