Article:The new trouble with fat cells

Active, powerful `glands' can spew toxic substances

Spare tires more dangerous than chubby backsides

DENISE GRADY
SPECIAL TO THE STAR

They are the building blocks of flab, the wages of cheesecake, the
bloated little sacks of grease that make more of us ‹ more than we can
fit into our pants. Scorned and despised, they are sucked out
surgically by the billions from bulging backsides, bellies and thighs.

But they are not without admirers.

"Fat cells are beautiful cells to look at," said Dr. Philipp Scherer,
an associate professor of cell biology and medicine at Albert Einstein
College of Medicine in New York. "I've been working with them for 10
years and I still enjoy looking at them.''

On a recent afternoon at his laboratory, Scherer slipped a Petri dish
of fat cells under a microscope and showed a visitor how strikingly
they caught the light and reflected it. Magnified, the cells became a
field of glittering rings. A mature fat cell, or adipocyte, contains a
huge, clear droplet of fat that takes up nearly the entire cell and
shoves the nucleus aside, squashing it up against the membrane so that
the cell appears empty. But it's actually a shining sea of fat, stored
as molecules of triglyceride.

Scientists used to think body fat and the cells it was made of were
pretty much inert, just an oily storage compartment. But within the
past decade research has shown that fat cells act like chemical
factories and that body fat is potent stuff: a highly active tissue
that secretes hormones and other substances with profound and sometimes
harmful effects on metabolism, weight and overall health.

In recent years, biologists have begun calling fat an "endocrine
organ," comparing it to glands like the thyroid and pituitary, which
also release hormones straight into the bloodstream. But there is an
important difference. Those glands cannot grow nearly as much as fat,
which has a seemingly infinite capacity to make more of itself. Too
much body fat can act like a poison, spewing out substances that
contribute to diabetes, heart disease, high blood pressure, stroke and
other illnesses, including some cancers.

Researchers trying to decipher the biology of fat cells hope to find
new ways to help people get rid of excess fat or, at least, prevent
obesity from destroying their health. In an increasingly obese world,
their efforts have taken on added importance.

A lean adult has about 40 billion fat cells, an obese one at least two
to three times that, and obese people have much larger fat cells than
lean ones. Even worse, the body can always make more, and compared with
other cells they are extremely long-lived. Though widely believed, it
is not true that a person's quota of fat cells is fixed forever
sometime in childhood.

Adults do not create new fat cells as readily as children do, but it
happens. If a person keeps overeating, the existing fat cells grow and
grow, looking as if they are about to pop, but there is a size limit.
When they reach that limit they do not divide, but instead send out a
signal to nearby immature cells to start dividing to produce more fat
cells.

It has been known for decades that some kinds of obesity are worse than
others. Body shape matters. People who are shaped like apples, carrying
excess weight in the abdomen, are more likely to have diabetes and
heart disease than are those built like pears, who deposit fat in their
hips, thighs and backsides. A person's tendency to store fat in one
place or the other is probably genetic, researchers say, though most
people will develop a big belly as the amount of excess weight rises.

Women tend to be pears, but they also redistribute fat and thicken in
the middle after menopause. Ethnic groups vary. For instance, Asians
are more likely than other groups to put weight in the abdomen and to
suffer health problems from lesser degrees of obesity.

Even a little too much abdominal fat ‹ an outsize gut on an otherwise
skinny person ‹ can increase the risk of high blood pressure, diabetes
and heart disease. Thin or average-looking people who actually are at
risk from belly fat may be falsely reassured by having a normal reading
on a common measurement of obesity, the body mass index, or BMI. The
problem is that the index, based on height and weight, does not take
body shape into account.

"We would like to eliminate the idea that BMI is the best indicator of
risk," said Dr. Osama Hamdy, director of the obesity clinic at the
Joslin Diabetes Clinic, in Boston. He said waist measurement is a
better predictor, with the danger zone being anything greater than 40
inches in men and 35 inches in women.

Why should a big belly be more dangerous than a big backside? Many
researchers think the culprit is visceral fat, meaning deposits inside
the abdomen, as opposed to subcutaneous fat, under the skin. An
apple-shaped person is sure to have visceral fat, as well as
subcutaneous fat in the abdominal area. Anybody with a belly has
visceral fat, and the more you have the worse off you are. It is not
clear why visceral fat is riskier; it may be more active metabolically
and spew out more toxic substances. In addition, its secretions go
straight to the liver and may interfere with its functions, which
include helping to regulate blood glucose and cholesterol.

Some studies even suggest that the cells in visceral fat are uniquely
active because they differ from other fat cells when it comes to which
genes are turned on or off.

A recent study published in the New England Journal Of Medicine lent
support to the notion that visceral fat is more of a threat than fat
under the skin. Doctors found that liposuction, which removes only
subcutaneous fat, had no effect whatsoever on health, even when
surgeons sucked out 20 pounds of subcutaneous abdominal fat. But a
person who lost that much weight through dieting and exercise would
almost certainly see significant changes in blood pressure, cholesterol
and insulin resistance.

Besides leaving visceral fat untouched, liposuction may fail to improve
health for another reason, said the first author of the study, Dr.
Samuel Klein, director of the Center for Human Nutrition at the School
of Medicine at Washington University in St. Louis. He said that while
liposuction removes billions of fat cells, it does not shrink the many
more left behind. Obese people have huge fat cells, with 50 to 75 per
cent more mass than fat cells in lean people, Klein said. Large fat
cells are not a good thing to have because research has found that they
are more active metabolically than small ones, and more likely to churn
out harmful substances.

The best way to get rid of visceral fat and shrink fat cells all at
once is diet and exercise. Even a small amount of weight loss, about 7
per cent of total body weight, helps. Researchers do not fully
understand why, but there is something about burning more calories than
you eat, creating a state of negative energy balance, that quickly
begins melting away the mass of visceral fat and slimming down bloated
fat cells. Indeed, most dieters find that belly fat comes off first and
that weight in the hips and thighs is much harder to lose.
Unfortunately, diet and exercise have high failure rates. Even those
who do manage to lose weight often regain it.

Since visceral fat is harmful and many people cannot lose it on their
own, researchers have been experimenting with surgical removal. Studies
in animals show that blood fats and other risk factors quickly improve
when the fat is taken out. In people, not all of the visceral fat can
be removed safely because of where it is situated.

But a portion called the "omentum" can be taken out relatively easily,
according to Dr. Edward Mun, a surgeon at Beth Israel Deaconess Medical
Center in Boston. It is a pad of fat weighing 2 to 4 pounds that hangs
like a curtain in the abdomen. "We estimate that it's more than
one-third of the visceral fat,'' Mun said.

He is doing a pilot study, performing the surgery in six obese,
diabetic patients to see if it can reverse their diabetes.

new york times

--
Diva
******
There is no substitute for the right food

One dark day on Usenet, Carol Frilegh said:

Active, powerful `glands' can spew toxic substances

Spare tires more dangerous than chubby backsides

DENISE GRADY
SPECIAL TO THE STAR

They are the building blocks of flab, the wages of cheesecake,
snip

Very interesting article, Carol --thanks for posting it...


--
J.J. in WA * 275/231/225 (mini)
(COLD to HOT for e-mail)

One dark day on Usenet, Carol Frilegh said:

Active, powerful `glands' can spew toxic substances

Spare tires more dangerous than chubby backsides

DENISE GRADY
SPECIAL TO THE STAR

They are the building blocks of flab, the wages of cheesecake,
snip

Very interesting article, Carol --thanks for posting it...


--
J.J. in WA * 275/231/225 (mini)
(COLD to HOT for e-mail)

Carol Frilegh wrote in message ...
Active, powerful `glands' can spew toxic substances

what an informative article...

somewhat similar to this website:

http://www.sportsci.org/encyc/adipose/adipose.html

"A lean adult has about 40 billion fat cells, an obese one at least
two
to three times that"

nice to have some actual NUMBERS for a change. I don't think fat
issues are linear with the number of fat cells, but since my balloon
up was stopped before things got way out of hand hopefully I didn't
quite react that 2x number. What that means for maintenance is an open
question still. I suppose with exercise it won't matter too much.

I've read somewhere that even existing fat cells, once stretched out
by fat uptake, are more a problem in keeping them unfilled in
maintenance.