High insulin levels hammer the hearts of obese teenagers

Carrying extra pounds means you’re increasing the chances of dying of a heart attack – someday.

For many of us, “someday” is far away, so although the risk is acknowledged, it doesn’t feel very real and so it hard to feel motivated to change our behaviour.

But “someday” may not be when you’re old and grey. If you’re carrying those extra pounds as a teenager – your heart may already be taking strain.

Fat teens fail a heart check up

Washington University researchers investigated the cardiac function of a selection of 77 teenagers (mean age 13.9 years). The teens that were part of the study had one thing in common – they were overweight, but did not have any other health problems.

The barrage of tests performed on the teens included :

an ECG (echocardiography) to check on how their heart was pumping
a lipid profile test, to see if they had high cholesterol
fasting plasma insulin levels
body mass index (BMI)

Lots of study participants failed the heart stress test.

Fat teen score card – mixed results

On the surface, cardiovascular health looked okay in all the teens. The ECG results showed pumping under normal circumstances was okay and cholesterol levels were normal in all participants.

So what is the fuss ?

When the teenagers’ hearts were pushed a little, many hearts started to splutter. Left ventricular global longitudinal strain, longitudinal systolic strain rate, and early diastolic strain rate were all significantly decreased in some of the teens.

Who failed the heart test ?

The level of fatness (BMI) was not what determined if the heart got a passing or failing grade on the heart test.

Failing the heart test was related to insulin levels. The higher the fasting insulin level, the more trouble the heart was in, when it was stressed.

Insulin resistance not so good for a heart under pressure

When the heart is stressed, it has to work extra hard. To work that little bit extra needs additional energy. The easiest way to boost the cell’s energy supply is to burn glucose (sugar).

Heart cells that are insulin resistant, run into trouble because they cannot get the sugar inside. No sugar means an energy crisis within the cell.

The energy crisis makes it hard for the heart to function normally.

Insulin resistance is a common problem

A diet high in carbohydrates pushes up insulin levels. Continuously high insulin levels often causes the cells to stop “listening” to the insulin, which leads to insulin resistance.

Most of us are insulin resistant to some degree. A blood test will tell you your status – a fasting level below 10 ulU/mL is normal, anything above this is considered to be a problem.

As a rule, if you’re overweight with a big tummy – you’re insulin resistant.

Rein in insulin for a happier heart

It’s never too early to start – if you’re thirteen or thirty, insulin resistance ups the pressure on your heart and contributes to blood vessel blockages. Take the load off – rein insulin in.

Insulin resistance is a determinant of cardiac dysfunction in obese children. ASE 2011; Abstract P1-72 Singh G, et al

Subscribe to E-spoons, to get e-mail updates once a month.

NOTE : Privacy & spam policy. Spoonful of Science will not rent, trade or sell the e-mail list to anyone. You can unsubscribe at any time by following the unsubscribe link.

Know someone who will find this post useful ? Share it on facebook, linkedi n, twitter