TUESDAY, Nov. 17 (HealthDay News) -- Surging obesity rates,
especially among children, may be putting the brakes on progress made in
the past few decades against heart disease, researchers report.

And it doesn't help that many obese or overweight Americans still
consider their weight "normal," as one study found.

One of several studies on the subject of obesity presented Tuesday at
the American Heart Association (AHA) annual meeting in Orlando, Fla.,
found that adults' blood pressure and blood sugar levels are continuing to
rise, fueled in large part by expanding waistlines.

This is swamping recent heart-health improvements such as lowered blood
levels of LDL ("bad") cholesterol or fewer people smoking, experts
said.

Poring over government data between 1988-1994 and 2005-2006,
researchers found that adult Americans' average body mass index (BMI) rose
from 26.5 to 28.8 over that time span. To put that in context, a BMI of 25
marks the beginning of overweight, while doctors use a BMI of 30 as the
threshold for obesity.

More people did achieve optimal LDL levels (22 percent versus 28
percent) and were non-smokers (rising from 45 percent to 50 percent)
during the same time period, but those gains were outweighed by fewer
people having good blood pressure (48 percent versus 43 percent) or blood
sugar control (falling from 67 percent to 58 percent).

In fact, "many people feel the decline in [heart] risk factors is
leveling off and there will be an acceleration of cardiovascular disease,"
said AHA spokesman Dr. Roger Blumenthal, professor of medicine in the
division of cardiology at Johns Hopkins School of Medicine in Baltimore.

Things don't bode well for the next generation, either: U.S. Centers
for Disease Control and Prevention statistics now put the number of obese
children and teens in the United States at about one-third.

"The prevalence of obesity and oversight in the U.S. and all developed
countries is on the rise and reaching epidemic proportions among both
adults and children," said Dr. David Crowley, lead author of a study on
child obesity and a cardiology fellow at Cincinnati Children's Hospital.
"In the course of the past three decades, the prevalence of obesity has
doubled or in some cases tripled across all pediatric age groups."

Not only have children and teens become heavier, their hearts have
become unhealthily thicker, as measured by left ventricular mass (LVM),
indicating a higher risk for heart disease down the line.

"Left ventricular mass is a marker of stress on the heart and a
predictor of heart attack and stroke," Crowley explained.

Between the mid-1980s and today, average BMIs in this sample of
children went from 18.1 to 19.9, while LVM jumped from 31.4 to 32.7. Males
and blacks fared worse than their female and/or white peers.

There were nearly twice as many overweight and obese children in the
later period compared to the earlier era: 35 percent versus 20 percent.
And the number of children with abnormally thick hearts more than doubled,
Crowley reported.

"The obesity epidemic is indeed having adverse effects on the hearts of
children compared to two decades ago," he said. "Today's children have
higher BMI and higher LVM and therefore are at a higher risk of heart
attack and stroke. If we do not get a handle on this in this country, if
kids continue to get heavier, their hearts will inevitably get thicker and
kids will be at higher risk of heart attacks and stroke."

Simple denial may be a component of this disaster, speculated a third
study. It found that a large proportion of obese people believe their body
size is normal and that they don't need to shrink. Some even believe they
could safely gain more weight.

Almost one in 10 surveyed said they were okay with the size of their
bodies after picking from a series of silhouettes the one they felt best
represented their image of themselves.

This same group also thought they were healthy, even though many of
them had risk factors for heart disease such as diabetes or high blood
pressure.

Ironically, individuals who were actually average or thin thought they
were larger than they really were.

"Obesity is not benign," noted study lead author Dr. Tiffany Powell, a
cardiology fellow at the University of Texas Southwestern Medical Center
in Dallas. "This underscores the need for us as physicians to understand
that we not only need to target those who have misperceptions in clinical
settings, but we also need to do work at developing community programs
targeting those who avoid the health-care system," Powell said.

"From our data, it looks like those who have misperceptions of body
size are much less likely to be seen by physicians," she added.

Two other groups of researchers at the AHA meeting presented yet more
reasons to lose weight. In one study, obese patients who lost weight saw a
healthy normalization of the chambers in the right side of the heart
(although it's unclear if this results in decreased risk for actual heart
problems). And in another study, weight-loss surgery reduced the size of
enlarged hearts. Enlarged hearts carry with them the risk of heart
failure.

More information

There's more on obesity's impact on heart disease at the American Heart Association.