1. ince the dawn of human
life, it has been with us.
Keeping us warm in cold
conditions. Storing the
energy we obtain from a
unique variety of foods
that the earth has given us to eat.
Protecting and padding the many complex
organs that move within us to keep us alive.
Encouraging balance within the metabolic
machines working under our skin. It is
essential for our health and existence. Yet
when it is mentioned it is associated with
disease. The World Health Organization
contributes the death of at least 2.8 million
adults worldwide each year to this naturally
beneficial entity within us. It is adipose
tissue, commonly called fat. And it is in each
and every one of us.
t would be wise for humanity to be
aware of the phenomenon that is
sweeping across the world. Although
most commonly attributed to the US,
obesity is prevalent in developed and
developing countries alike. It is true that
obesity is causing a worldwide epidemic.
Many factors have accelerated the
magnitude of obese individuals throughout
the world. The human diet has changed.
Workplaces force people to be sedentary
for a large portion of the day. Humans now
have transportation that takes them where
they desire. It is important to be aware that
obesity is on the rise, and that it is making
the world sick. And the numbers to prove it
are shocking.
The World Health Organization (WHO) has
estimated that 65% of humans live in
countries where obesity is the primary
cause of death. Continents experiencing
increases of obesity in populations range
from North America to Europe to Australia
and Asia too. The population of obese
human beings has doubled in size since the
year 1980. More recently, it is not only
adults who are becoming overweight and
obese. WHO has also found that a projected
4 million children under the age of 5 were
overweight in the year 2011. European
countries account for a large portion of that
number. These statistics are powerful
representations of just how prevalent
obesity has become around the world, and
how widespread it is throughout very
different populations and cultures.
dipose tissue within the human
body is meant to have a positive
impact on metabolic processes. It
has been well established that an over
accumulation of adipose tissue within the
visceral cavity causes metabolic syndrome.
There have been many changes in the
human diet, lifestyle and genome over time
All three of these have been contributed to
obesity through various studies done by
scientists around the world in response to
the obesity epidemic.
S
I A
Visceral Obesity
The Culprit of Metabolic Disease
By Emily Roderick

2. The Evolution of our Diet
Dr. Loren Cordain, most prominently known
for creating the Paleo Diet, has done a
significant amount of research on how the
human diet has changed over time. Cordain
suggests there have been drastic changes in
the human diet ever since humans began to
practice agriculture (the raising of crops)
and animal husbandry (the raising of farm
animals). These anomalies gained
widespread popularity in a short amount of
time relative to the entire existence of
humanity. The human species does not
have the capability to evolve with such
speed. Humans are unable to mold the
metabolic processes within their bodies
that were once optimal for the survival of
our early ancestors to suit our modern
diets.
Food products such as dairy, cereal grains,
and refined vegetable oils were not
available for human consumption until we
realized our capability to raise animals and
crops to suit our desires. The nutrient
content of plants that we grow and by-
products from the animals we nurture is far
different from the food once hunted and
gathered. The farm-raised meat we now eat
contains far more fat than that of the wild
game our ancestors once hunted. We have
found a way to refine sugars and we have
managed to put them in just about
everything. Dairy, cereal grains and refined
sugars each have their place on the
glycemic index, which indicates that they all
increase blood sugar levels when
consumed.
Four new sources of foods (cereal grains,
refined sugars, refined vegetable oils, and
dairy) with high energy density in the
human diet were introduced by the sewing
of seeds and breeding of farm animals. The
sugar from these foods can be converted
into fat in our bodies. Of course it is not as
simple as that. Sugar cannot be converted
directly into fat. When sugars are
metabolized, they are eventually broken
down into acetyl CoA. Acetyl CoA can be
converted into fatty acids, which make up
fat. Contrarily, the proteins from these
foods can be converted directly into fat.
These new sources of foods either contain
high quantities of fat or have the potential
of somehow becoming fat. High intake of
dairy, cereal grains, refined sugars and
vegetable oils are making stores of fat grow
larger.
The Genetics of Obesity
A much newer explanation for the increase
in obese individuals has been explored by
Tove Fall and Erik Ingellson, both part of the
Department of Medical Epidemiology and
Biostatistics at the Karolinska Institutet in
Stockholm, Sweden. They conducted a large
research project in which they investigated
the role of the human genome in the
predisposition for obesity. The human
genome contains the genetic information of
our species and it may have a large
influence on the occurrence of obesity
passed down from generation to
generation.
Fall and Ingellson looked at 39 studies that
have linked certain genes to obesity. They
came across noteworthy accounts of genes
influencing obesity. One significant article
described a gene called fat mass and
obesity associated, aka FTO. FTO was one of
the first genes to be directly tied to obesity.
Interestingly, a strong correlation was
found between the presence of this gene in
adolescents and sever childhood obesity.

3. This gene had most widely been found in
people who were of European descent. This
finding set off a domino effect in the
research of genome-wide influence on
obesity.
Many genes have since then been identified
to have an influence on obesity in various
ethnic groups through numerous studies
examined by Fall and Ingellson. These
findings have proven to be helpful in the
prediction of onset of obesity throughout
families who have a predisposition for the
expression of these obesity associated
genes.
The Sedentary Lifestyle
A sedentary lifestyle can largely contribute
to obesity. It cannot be overlooked when
exploring why obesity has been caused to
proliferate. Dr. Manson of the Department
of Epidemiology at the Harvard School of
Public Health in Boston, Massachusetts
published a 12 page call to action in 2004,
describing the severity of obesity and its
direct association with a sedentary lifestyle.
She went as far as to set in place a
“blueprint” for physicians to follow in
directing their patients to a healthier way of
life.
Manson describes the burden of disease
among the rising obese population and the
economic losses due to health care costs.
Manson estimates that around $90 billion
dollars is annually spent treating individuals
with obesity caused metabolic dysfunction,
amounting to about 10% of the total money
spent on healthcare each year in the US
alone. Manson suggests that “weight loss
and physical activity offer substantial health
benefits”. Just through lifestyle changes, a
large number of this population can prevent
and even reverse the health consequences
they so often experience.
n May of 2013 the US National Lipid
Association published a consensus
statement titled Obesity, Adiposity, and
Dyslipidemia. In this report they state that
an escalation of adipose tissue growth in
one’s body can actually trigger a pathogenic
response within the adipocytes themselves.
The US National Lipid Association uses the
term adiposopathy to describe what they
refer to as “sick fat”. This sick fat can
manifest itself in various forms of metabolic
disease. The most common diseases
associated are dyslipidemia, insulin
resistance, type II diabetes and
hypertension.
Dyslipidemia
The US National Lipid Association uses the
term dyslipidemia to describe an abnormal
numbers of lipids within our blood. The US
National Lipid Association states in their
2013 consensus statement that
dyslipidemia can often be caused by taking
in more calories than we can use (referred
to as positive caloric balance). Adipose
tissue does not have the holding ability to
take up all of the lipids being ingested,
which can lead to over storage of lipids
within non adipose tissues such as liver
tissue and muscle tissue. The over storage
of lipids often results in lipotoxicity,
meaning there are toxic amounts of lipids
within non-adipose tissues. In this case,
lipids are being stored where they don’t
belong. In response to lipotoxicity, the cells
become sick and cannot function properly.
This toxicity becomes a problem because
these non-adipose tissues are responsible
for the breakdown of lipids. The adipose
I

4. tissue cells, once over filled, begin to
secrete a variety of different hormones and
enzymes in abnormal ways. These
secretions begin to cause disarray among
the internal organs of our body. Functioning
normally, adipocytes secrete enzymes that
aid in pulling individual fatty acids off of
their glycerol backbone which creates free
fatty acids. The free fatty acids are then
able to be taken up by different tissues like
muscle or adipose to be stored or used as
building blocks for cells and energy
production. If adipocytes are not properly
functioning, they will not secrete these
enzymes and free lipids are left floating
through the bloodstream.
Type II Diabetes
Type II diabetes is very closely tied to one’s
lifestyle. It can be prevented through
proper diet and exercise. Yet, it is on a
steady rise throughout the world. This
disease comes about when the body does
not respond to insulin being created by the
pancreas and can often be in response to
over stimulation of insulin receptors from
excessive intake of carbs and sugars in the
diet.
Amalia Gastaldelli, from the National
Research Council based out of the Institute
of Clinical Physiology in Pisa, Italy, has
observed from studies that free fatty acids
(FFAs) have a heavy interaction with the
liver. The liver takes up the FFAs that are
not absorbed by other tissues. When there
are too many FFAs in circulation, they can
lead to insulin resistance within the liver
itself. Insulin is a very important hormone
which plays a large role in carbohydrate and
lipid digestion. It promotes the absorption
of glucose and lipids flowing through the
bloodstream following a meal. Glucose can
be stored in the form of glycogen within our
liver and muscle tissues to be used in the
future as an energy source. Lipids can be
stored in adipose tissue. If our tissues are
not responsive to insulin, then our bodies
will not take up and store glucose and lipids
from the foods we are eating. If there is
insulin resistance in the liver then it will
Illustration by World Obesity Federation
Almost every country in the world is experiencing the obesity epidemic to some extent. This map shows the spread of obesity
throughout the countries of the world.

5. have limited intake and storage of glucose.
When the liver does not have adequate
amounts of glucose, the body resorts to
gluconeogenesis to produce glucose for
fuel. Gluconeogenesis is not a favorable
metabolic pathway and is only meant to be
used during periods of prolonged fasting.
Hepatic (meaning in the liver) insulin
resistance triggers unnecessary
gluconeogenesis.
To relate this back to adipose tissue,
researchers have found that if adipose
tissue is not functioning properly, it can
create an influx of free fatty acids in
circulation, which can lead to insulin
resistance.
In the study described by Gastaldelli,
individuals found to have type II diabetes
caused by visceral obesity were put on a
low calorie diet and were told to exercise.
Following this diet/exercise program, many
of the symptoms of type II diabetes were
decreased, which demonstrates that this
disease is reversible. This is a very popular
topic for research and many scientists have
found heavy correlations between visceral
obesity and the occurrence of type II
diabetes.
Hypertension
Hypertension is a medical term for high
blood pressure. Researchers from Sapporo
Medical University School of Medicine,
Sapporo, Japan screened the adult
population from a rural community and
have found strong correlations between
visceral fat accumulation and hypertension,
specifically in the male population. They
think that the reason for an increase in
blood pressure due to visceral fat
accumulation is in response to insulin
resistance. Hypertension can have very
negative effects on the heart and
circulatory system if not monitored and
treated effectively.
The American Heart Association (AHA)
supports an article done by Wayne
Alexander from the Division of Cardiology at
Emory University School of Medicine in
Atlanta, Ga. This article specifically looks at
the effects that hypertension may have on
atherosclerosis, one of the major risk
factors for heart attacks in adults.
Metabolic Issues Associated
With
Visceral Obesity
Whether it be bad diet, a sedentary lifestyle, or a
genetic predisposition, visceral obesity can cause a
wide variety of metabolic issues within the human
body.

6. The AHA provides that atherosclerosis
results when free lipids and lipid derivatives
(often in the form of cholesterol within the
blood stream) begin to build up, and when
not properly addressed can cause the blood
supply to be cut off. This of course is also
very related to dyslipidemia as excess
amounts of lipids in your blood stream can
lead to build up (referred to as plaque) in
the arteries. In fact, Alexander has found
that only when hypertension and
dyslipidemia are working together do they
lead to atherosclerosis. Both contribute in
different ways to the production of plaques
in the arteries, and both are most
commonly contributed to visceral obesity.
The effects of these diseases are
concerning for the human population. It
is becoming more and more common
that individuals express one or more of
these metabolic diseases. People who
are experiencing hypertension, type II
diabetes and dyslipidemia are not
experiencing a good quality of life and
many times these diseases result in
early death.
nterestingly, it seems that the location
of the adiposity within the body has a
heavy influence on whether or not it
will cause metabolic dysfunction. Many
researchers have found that when obesity is
found in subcutaneous tissue (that found
under the skin), it is relatively harmless. It is
the visceral adipose tissue (found around or
within internal organs) most often
attributed to the apple shaped body that
has been found to cause disease in humans.
These are the same tissues that cradle and
protects our organs. It has been found to
cause the most harm when it becomes
overgrown and ill. This is the type of fat that
is causing metabolic disease.
The Physiology
Taking a look at adipose tissue and how it
functions in the body may help to better
understand why it can cause disease.
Historically, people thought that adipose
tissue functioned mainly as an energy
storage site (which is a large role that it
plays). The lipid holding cells that make up
adipose, called adipocytes, resemble
clusters of yellow grapes which can range in
size. The lipids contained within these cells
hold potential energy for our body to use in
a fasting state, when available energy from
diet is low. The role of adipose tissue as a
lipid storage site is essential for the human
body to function normally.
Researchers now know that adipose tissue
also plays an important role in the immune
defense system, and it even acts as an
organ of the endocrine system due to its
capability to secrete hormones and to
receive hormone signals.
Through metabolic processes such as
lipolysis and glycogenolysis, the human
body has the ability to produce energy from
lipids and glucose storages. Lipolysis is our
body’s ability to break down triglycerides,
which are the form in which the human
body stores lipids within adipose tissue, into
free fatty acids and glycerol.
It is important to know the structure of a
triglyceride to understand how they are
broken down within our bodies. Think of a
triglyceride as a jellyfish. The bell of this
jellyfish is made up of glycerol, a water
soluble alcohol. Attached to this glycerol
bell are three tentacles. Each tentacle is its
own fatty acid chain. There are 20 different
fatty acid chains, and the three fatty acid
tentacles can be in any order or
combination along the glycerol bell.
I

7. Used as a source of fuel for many tissues
and as important structural elements of
cells, free fatty acids play many significant
roles in the human body. Although our
bodies have other ways of storing energy,
lipids hold as much energy as carbohydrates
(mostly made up of glucose) and proteins
combined.
Glycogenolysis is the process in which the
body breaks down glycogen, the storage
form of glucose, into individual glucose
molecules which can be used for energy.
Glucose is very essential as it is the main
fuel source for both the brain and red blood
cells. This is important in relation to lipids
stored in adipose tissue. If someone goes
without eating carbohydrates for more than
18 hours, the body’s glycogen stores will be
all used up and the body will be void of
glucose. The body must produce glucose
somehow to avoid damage to the brain. The
glycerol bell found on the triglyceride
jellyfish, after being broken apart from the
fatty acids through lipolysis, can be
converted into glucose through a process
known as gluconeogenesis. The purpose of
this process is to form glucose from non-
carbohydrate sources, such as glycerol.
Adipose cells can become enlarged and can
multiply. Both of these processes are
reversible. Enlargement of adipocyte cells is
caused by an excessive intake of lipids that
the body could not possibly use up. This
leads to the physical expression of what is
recognized as obesity in individuals. This
swelling capability of adipose tissue is an
ingenious feature the human body created
years ago to store energy for later use when
food was not so readily available. Now food
is prevalent in developed countries of the
world and our caloric intake has increased
drastically. The lives of human beings have
become more sedentary and we do not
require as much energy day to day.
Measuring Obesity
There are many tests and formulas that
have been created over the years to
measure obesity, but the most universal
measurement used throughout the world is
the Body Mass Index, abbreviated BMI. This
system uses weight in proportion to height
to determine where an individual falls on
the BMI chart, which ranges from
underweight to obese. Doctors take the
weight of the individual and divide that by
their height to give a number somewhere
between around 15 and 40+. A BMI of I5
would indicate someone as severely
underweight whereas a BMI of 40+ would
indicate someone as severely obese. A
healthy BMI is considered to be between
18.5 and 25. Although this measurement is
not flawless due to factors such as muscle
mass, it has been the most effective around
the world in classifying individuals as obese.
Another useful, popular measurement
technique is the skin fold thickness test. The
goal of this test is to measure subcutaneous
fat using a clamp-style tool that pinches
your skin together and measures the
thickness. With some simple calculations,
you can determine the percentage of
subcutaneous fat in your body. With BMI,
skin fold thickness, and another simple
measurement called hip to height ratio can
all be used together to gauge the amount of
visceral fat an individual has.
While the methods previously explained are
useful, inexpensive, and easy to do, they
are not useful for measuring visceral body
fat accumulation. This just may be the most
important type of body fat to measure

8. when metabolic dysfunctions arise. A
simple measurement of waist
circumference, when analyzed along with
BMI can vaguely and inexpensively measure
the amount of visceral obesity in an
individual. This measurement is nowhere
near exact, and most scientists strongly
support other methods that are more
precise in measuring visceral obesity.
In a study done by Dr. Shiga, from the
Research and Development department of
Omron Health Care Inc, Ltd in Tokyo Japan,
he mentions that the “gold standard” for
measuring visceral fat accumulation is CT
imaging, which basically involves an X-ray of
the abdominal area of an individual.
Unfortunately, this method is expensive
making it inaccessible to a large portion of
the world’s population, and it also has
associated health risks due to the radiation
produced by the x-ray. This method is the
most reliable in clinical settings because you
can target specific organs within the body
to measure the amount of fat accumulation
within the organs themselves.
Dr. Shiga suggests another method.
Bioelectrical impedance analysis. This is
essentially a test that uses electrical
currents to measure the volume of body fat
in an individual. Electrodes are attached to
the individual, which create currents that
flow through the abdomen. Researchers
can then read the resulting measurements,
which will vary depending on how quickly
the currents are able to pass through the
individual’s body tissues. Electricity travels
much slower through fat than it does other
tissues of the body such as bone or muscle.
By using a special formula, they can
specifically measure the visceral fat volume
(VFV). This method does require expertise,
but it is safe and reliable, making it a
favorable method for the measurement of
visceral adipose tissue.
There are many more techniques used for
measuring obesity that are used
prominently throughout the world, and
many times the method of measurement is
dependent on what types of fat and areas
of accumulation doctors or scientists are
interested in observing, as well as how
much money and time are available.
Research Provides Insight
Dr. Michelle Foster, an assistant professor
in the Department of Food Science and
Human Nutrition at Colorado State
University, does research pertaining to
adipose tissue in hopes of discovering new
links between subcutaneous and visceral
adipose tissue, and how their location
within the body can influence metabolic
disease. She has had the opportunity to
observe and measure direct health
consequences and improvements related to
adipose tissue distribution, removal and
transplantation. Foster carries out her
research by surgically removing and
transplanting two different types of adipose
tissue, subcutaneous and visceral, into or
out of mice and rats.
In one experiment, Dr. Foster surgically
removed non-visceral adipose tissue and
visceral adipose tissue from the abdominal
cavities of two different groups of rats. The
mice that underwent visceral fat removal,
specifically from sights that drain into the
hepatic-portal system (which transports
blood to the liver) showed significant
metabolic improvements. The mice who
received the adipose tissue transplant had
significant decreases in metabolic

9. dysfunction. These findings show how
health consequences are not just attributed
to an excess of visceral adipose tissue
accumulation. The consequences are very
dependent on the precise location of
adipose tissue accumulation.
In another experiment, Dr. Foster wanted
to see what would happen if subcutaneous
tissue was removed from an obese mouse,
and placed into the visceral cavity of
another mouse. Results showed that the
health of the mouse declined following the
removal of the subcutaeous fat which
would implicate that subcutaneous tissue--
contrary to popular belief--is essential for
our health. The fat that is the primary
contributor to the aesthetic expression of
fat in obese individuals is not the culprit of
metabolic disease. It is actually a large
storage site that helps cleanse our system
of abundant amounts of dietary lipids and
cholesterol.
The transplant of subcutaneous tissue into
areas of visceral dysfunction has potential
as a solution of obesity-induced metabolic
disease. This study also shows that
metabolic issues arising from obesity within
visceral fat can actually be reduced and
even reversed with the transplant of
subcutaneous fat into the visceral cavity.
Think of visceral adipose tissue as a sponge,
surrounding your organs and absorbing
extra lipids present in your body. These
sponges can only become so saturated, and
there are only so many present within your
visceral cavity. Once they become
saturated, they begin to malfunction. By
adding more sponges, you have a higher
storage capacity of healthy fat cells, and
metabolism will return to homeostasis.
Obese mice with metabolic health issues
that underwent this adipose tissue
transplant procedure performed by Dr.
Foster had noticeable improvements in
health after just 4 weeks. In this case,
subcutaneous fat transplanted into the
visceral cavity was able to mimic the
visceral fat, resulting in an expansion of the
holding capacity of the abdominal adipose
tissue.
The implications of Dr. Foster’s research
provide insight as to the difference of
function between subcutaneous and
visceral adipose tissue within the body.
Subcutaneous adipose tissue encourages
balance in the body, where visceral adipose
tissue discourages balance in the body.
t has been scientifically tested and
proven time and time again that the
accumulation of visceral fat (VF) has
negative consequences on the health of
individuals. Furthermore, these ailments
have been associated most strongly with
the adult population. The most common
found health issues linked to VF buildup are
dyslipidemia, hypertension, and type II
diabetes (in response to insulin resistance).
These metabolic diseases are indirect
effects of adipose tissue dysfunction.
The science supporting visceral obesity
as a cause of deadly and expensive
metabolic dysfunction is overwhelming.
Through proper diet and exercise, many
of these diseases can be prevented.
Even individuals who are already
predisposed to obesity because they
express obesity related genes. Many
researchers including Dr. Foster of
Colorado State University and Dr.
Manson of the Harvard School of Public
Health are looking for answers and
solutions to the ever increasing issue on
I

10. hand. If the world began to focus in on
this issues they could save millions of
lives, and billions of dollars each year. It
is entirely up to the individual to take
control of their diet and activity levels
to either combat or prevent the onset
of visceral obesity.
Looking at a single adipocyte cell may
seem like a small matter. But where
there is one adipocyte, there are many.
Where there are many adipocytes,
adipose tissues are formed. These
tissues interweave themselves within
the organs of the human body. These
organs have important functions and
are essential for the life of human
beings. If a single, or a few, or many
adipocytes become sick, the effects can
spread in dangerous ways leading to a
sickness deep inside. Be aware of your
body and take care of it. Many diseases
are not preventable. Stop the ones that
are.
______________________________________________________________________________
Contacts for more information…
World Health Organization
Avenue Appia 20
1211 Geneva 27
Switzerland
Telephone: + 41 22 791 21 11
www.who.int
American Heart Association
National Center
7272 Greenville Avenue
Dallas, TX 75231
USA
www.heart.org
World Obesity Federation
Charles Darwin House
12 Roger Street
London, WCIN 2JU
United Kingdom
Telephone: +44 20 7685 2580
www.worldobesity.org
National Lipid Association
6816 Southpoint Parkway, Suite 1000
Jacksonville, FL 32216
USA
Telephone: 904 998 0854
www.lipid.org
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304-383.
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Origins and evolution of the Western diet: health implications for the 21st century. The American Journal of Clinical Nutrition, 81,
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Foster, M.T., Softic, S., Caldwell, J., Kohli, R., deKloet, A.D., & Seeley, R.J. (2013). Subcutaneous adipose tissue transplantation in diet-induced
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Role of Hepatic Triglyceride Storage. Physiol Behav, 104, 845-854.
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