People who are obese probably already know that they're more
likely than lean people to develop heart disease and
diabetes. But they may not realize that they are also at
increased risk for a range of gastrointestinal (GI) diseases,
including fatty liver disease, gastroesophageal reflux
disease (GERD), gallbladder disease, severe pancreatitis and
some GI cancers.
Having excess body fat means not just having excess fat
inside fat tissue, but also having excess fat in organs,
including the gastrointestinal organs, particularly the
liver. Having excess fat in the liver causes liver
dysfunction and even can lead to serious long-term liver
disease. For example, if you're obese and have diabetes and
hypertension, you have about a 75 percent chance of having
fatty liver disease.
Normally, nutrient-rich blood passing from the stomach and
intestines through the liver is converted into energy when
carbohydrates, protein, fats and minerals are processed. But
the metabolism of excess fat and the subsequent increase in
fatty acids can damage the liver, impairing its functions
such as regulating blood sugar levels by storing glucose for
later use. Fat in the liver can begin as nonalcoholic fatty
liver disease, which resembles the damage to the liver done
by alcohol abuse, and progress to cirrhosis of the liver, in
which liver cells are replaced by scar tissue. As a result,
liver disease due to obesity is a leading cause of liver
transplantation in the United States.
Obesity is also a risk factor for GERD, a condition that
affects the lower esophageal sphincter, which is a muscle
that acts as valve between the esophagus and stomach. In
GERD, this valve doesn't close, so contents from the stomach
slip back up into the esophagus, causing heartburn and acid
indigestion. Losing weight, especially if people improve
their diets in the process, can ease GERD symptoms.
The relationship between weight and gallbladder disease is a
more complex one. Gallbladder disease is characterized by the
development of gallstones, which are balls of solid material
— usually mostly cholesterol — that form in the
gallbladder when it cannot dissolve all of the cholesterol in
bile, or when the gallbladder is not emptying properly.
People who are obese, particularly obese women, have a much
higher risk of gallstones than non-obese women. But losing
weight initially increases your risk of having gallstones
because weight loss itself changes the composition of bile.
Gradual weight loss, as well as exercise, is thought to
result in lower gallstone risk. And after someone has
maintained weight loss, their risk of gallstones goes
down.
While obese people are not more likely to get pancreatitis,
or inflammation of the pancreas, they are more likely to have
a severe form of it. The reason for that is unknown. It might
be due to excess fat around the pancreas that gets digested
by leaky pancreatic enzyme, releasing fatty acids and toxic
products around the pancreas.
Additionally, colon and rectal cancer have been found to
occur more often in people who are obese than in leaner
people. And a recent study found a link between liver cancer
and obesity. Although its not understood how obesity
increases cancer risk, it's thought to be due to a genetic
predisposition combined with a poor diet.
Specialists recommend screening for GI conditions for all
people who are obese, particularly if they also have high
cholesterol, high blood pressure and/or diabetes. It's
important to recognize that, in addition to the diseases we
associate with obesity — diabetes, hypertension and
heart disease — being overweight can also increase risk
of GI disease. These diseases need to be on the radar
screen.
2004 Dr. Reuven Bruner. All Rights Reserved.
For more information contact him at: POB 1903, Jerusalem,
91314, Israel; Tel: (02) 652-7684; Mobile: 052 2865-821; Fax:
(02) 652-7227; Email: dr_bruner@hotmail.com
