official definition of Leaky Gut Syndrome is an increase in
permeability of the intestinal mucosa to luminal macromolecules,
antigens, and toxins associated with inflammatory degenerative
and/ or atrophic mucosa or lining.
more simply, large spaces develop between the cells of the
gut wall allowing bacteria, toxins and food to leak into the
of our immune system is located around the digestive system.
In a normal healthy person the small intestine behaves like
a selective sieve allowing only the breakdown products of digestion
into the bloodstream. 
Nutrients and well digested fats, proteins and starches are
readily able to enter into the bloodstream whilst large molecules,
microbes and toxins are kept out.
the intestinal tract, villi (finger like projections off the lining
the intestinal tract with hair like cell membrane extensions called
microvilli), serve as a point of absorption of nutrients. Nutrients
such as glucose, amino acids or electrolytes are carried through
the microvilli into the cells of the villus via active transport
(carrier molecules take the nutrients across the cell membrane).
Leaky Gut Syndrome causes the intestinal lining to become inflamed
and the microvilli become damaged or altered. The damaged microvilli
cannot then produce the necessary enzymes and secretions that are
essential for a healthy digestion and the absorption of nutrients.
between cells reside desmosomes. These adhere adjacent cells together
to form a strong, sturdy structure, which prevents large molecules
from passing through. When an area becomes inflamed this weakens
the structure of the desmosomes and larger molecules can escape
through. This provokes the immune system to produce antibodies (a
protein utilised by the immune system to locate and attack foreign
objects) to fight off the molecules, as they are perceived as antigens
(substances capable of triggering the production of antibodies).
healthy individual would have a strong enough immune system to control
the leakage of toxic substances but as it becomes over loaded the
toxins leak into the liver resulting in an overworked overburdened
liver is the largest gland in the body and plays a really important
part in detoxification as well as having many other functions including:
producing bile, containing bile acids, which aid digestion, filtering
out toxins, such as drugs, alcohol and environmental toxins, storing
glucose as glycogen, then breaking it down about 4 hours after a
meal to be converted to glucose to regulate blood sugar levels,
converting ammonia to urea and removing damaged red blood cells.
Gut completely overworks the liver because it floods it with additional
toxins diminishing the liver's ability to neutralise chemical substances.
When it cannot cope with the level of toxins the liver expels them
back into the bloodstream. The circulatory system then pushes the
toxins into the connective tissues and muscles where the body stores
them to prevent major organ damage. The liver doesn't get the time
to go back and rid the body of the toxins.
As the intestinal lining becomes more and more damaged substances
larger than particle size such as disease causing bacteria and fungus,
potentially toxic molecules and undigested food particles pass through
the weakened cell membranes. These enter the bloodstream, triggering
antibodies and cytokines (protein molecules released by the immune
system to cause a reaction in other cells) to fight the antigens.
The cytokines alert the lymphocytes (white blood cells) to fight
the particles that have escaped through the intestinal lining. Toxic
oxidants are produced as a result causing allergic reactions and
more inflammation throughout the body.
The digestive tract is normally coated with a mucus layer, which
keeps out foreign substances. Leaky Gut Syndrome develops as the
mucus layer is weakened and the bacteria, which usually resides
in the intestine starts to inhabit other parts of the body as well
(bacterial translocation), due to the intestinal permeability.
So put very simply your intestine develops leakages allowing substances
that would normally be digested to enter the bloodstream. These
toxins are passed onto the liver to deal with but it cannot cope
with the overwhelming toxins and stores them in the body tissues
to come back to later on. The liver is too overworked to go back
to the toxins and as the intestinal lining gets consistently weaker
more and more toxins and undigested food enter into the bloodstream.
The immune system sends out antibodies to fight these foreign substances
and in doing that toxic oxidants are produced which attack the body
tissues causing allergic reactions and pain and inflammation throughout
Spaeth G, Berg RD, Specian RD, Deitch EA, August 1990, "Food
Without Fiber promotes bacterial translocation from the gut"
Surgery 108 (2) pp 204-47
 Sharma R, 2005, Leaky Gut Syndrome, article.
E Leaky Gut Syndrome, 1998, "What to do about a health threat that
can cause arthritis, allergies and a host of other illnesses" p10
 Gilbere G, 2001, I Was Poisoned By My Body...I Have A Gut Feeling
You Could Be, Too, p10, Lucky Press.
G, 2001, I Was Poisoned By My Body...I Have A Gut Feeling You Could
Be, Too, p11, Lucky Press.