By
Dr. John McDougall
Out of the Mouths of Babes
Many years
ago on one summer evening when our daughter was 10 and our oldest son
was nine, we were enjoying a peaceful dinner when Heather asked, “Is
there something wrong with Jodi?” Heather and Patrick had spent the
previous night at their best friends’ home, Jodi and Mark. Heather
continued, “When Jodi is in the bathroom I hear these strange noises,
like she is in horrible pain.” She then made a long painful grunting
sound to demonstrate. Patrick interjected, “Mark makes the same noises
and he’s in there forever.” My children had never had to experience the
Herculean exertion most people require to move their bowels. In fact,
for them this daily process was accomplished effortlessly and in seconds
– back out to play before the ball stops bouncing.
Almost 30
years ago, as a general practitioner in a small rural community on the
Big Island of Hawaii, I had a chance to learn all about the personal
bowel habits of my patients. The most upsetting stories were about the
suffering children. Mothers often brought them to see me because of
lower abdominal pains and bleeding – blood on the toilet tissue or frank
blood in the toilet bowl. After detailed questioning, the concerned
mothers told me about the straining efforts their children experienced
with each bowel movement, every two to five days. No connection was
ever made between the child’s diet and this severe constipation. Nor
by patients, and nor by their concerned doctors, is there ever any
connection made between this constipation and diseases in other parts of
the body.
The Fiber
Man – Denis Burkitt
All of my
formal medical-school education focused on describing and treating the
signs and symptoms of chronic illness, rather than on really important
matters – cause and cure. A turning point in my life came in the autumn
of 1971, when I was a senior medical student. During a noontime
hospital conference I met the first doctor to tell me there were causes
for the common chronic diseases. Dr. Denis Burkitt was visiting the
Kellogg cereal company in Battle Creek, Michigan; trying to convince
them to add more dietary fiber to their products. He believed the lack
of fiber in our diet was at the root of our common chronic diseases.
Dr. Burkitt,
born in Ireland in 1911, became a surgeon at Edinburgh’s Royal College
of Surgeons in 1938, and was assigned to work for the colonial Medical
Services in Uganda, Africa in 1946.1 He served as the Government Surgeon of Uganda from 1946 to 1964. Here
he discovered a cancer of the immune system, which carries his name –
Burkitt’s lymphoma.
In Uganda,
Burkitt made many important observations about his African patients.
For example, they produce several times more quantity of feces than
people on the highly refined, high meat Western diet. He noticed their
feces were soft and passed without pain and attributed this to the high
fiber content of their foods. Westerners have 3 to 21 bowel movements a
week and the amount of stool passed is 85 to 150 grams/day (3 to 5
ounces). Africans have 30 to 60 movements a week with a stool weight of
200 to 500 grams a day (7 to 17 ounces). Most importantly, he noticed
that the diseases he had been trained to treat in Scotland were absent
among Africans. He saw no cases of type II diabetes, obesity,
appendicitis, diverticular disease, hemorrhoids, dental caries, varicose
veins, pulmonary embolism, inflammatory bowel diseases (Crohn’s disease
and ulcerative colitis) or hiatus hernia. The only heart attack he saw
was in a judge who had trained in London, developed a taste for roast
beef and Yorkshire pudding, and then returned to Africa. “In 20 years
of surgery in Africa, I had to remove exactly one gallstone,” Dr. Burkitt claimed.
I remember
only one slide from this “medical-student, mind-changing” lecture. On
one side of the slide was pictured a large hospital building with a
small bowel movement next to it; and in the adjacent frame was a small
hospital with a large stool. The message was clear – those populations
who eat a diet high in fiber have big bowel movements and few
illnesses. Denis Burkitt set out in the mid-1960s to tell the world how
important it was to add fiber back to your diet. He became known as
“The Fiber Man.” In retrospect, his focus was too narrow – simply
sprinkling bran over bacon and eggs will not solve the health problems
of Western man.
Historically, similar changes in disease patterns, as seen in Africa,
have been seen as the diets of people in England, the United States, and
most recently Japan, have switched to processed foods and animal
products.2-4 There are many more important qualities to the plant-based diet of
Africans than the fact that it was high in dietary fiber. The African
diet has been traditionally a diet based on grains, legumes, vegetable
and fruits – his patients ate very little meat, dairy products or
refined foods. This means the diet was very low in animal protein, fat
and cholesterol, and high in complex carbohydrates, dietary fiber, and
healthful phytochemicals.5-6
All these ingredients go together to define a healthy human diet – like
that of Burkitt’s patients (and by no coincidence, The McDougall Diet).
In last
month’s newsletter I explained that fiber, which is only found in plant
foods, is mostly non-digestible carbohydrate, which passes through the
small intestine intact to become the bulk of the stool. The fiber pulls
in water to further expand the volume of the stool. Americans eat very
little fiber because their meals are made of mostly fiber-free animal
products and refined grains. The result is tiny rock-hard fecal marbles
– and so begins health problems throughout the body. The following
diseases are found commonly in populations of people who consume a
“rich” diet, and are essentially unknown in people, who, like Dr.
Burkitt’s Africans, consume a diet based on unrefined plant foods.
Appendicitis:
The contents
of the small intestine empty into the large intestine. The first part
of the large intestine is called the cecum (located in the right lower
part of the abdominal cavity). A small pouch or diverticulum, called
the appendix, is attached to the cecum. When the opening of the
appendix becomes blocked, fluids accumulate. These stagnant fluids
become infected creating a disease condition common to Westerners,
called appendicitis.
The cause of
this blockage is unhealthy remnants of partially digested foods, which
irritate the opening of the appendix. The observation that
appendicitis is unknown in populations of people who eat a plant-based
diet must be surprising (and maybe disappointing) to surgeons trained,
like Dr. Burkitt, to treat this common condition in Westerners.7-9 The incidence of appendicitis is increasing among Africans as their
diet changes.10
Diverticular Disease:
In Western
societies, diverticulosis occurs in at least one person in two over the
age of 50 years. The frequency increases with age. Denis Burkitt,
practicing in Uganda, and doctors taking care of similar populations of
people, never see this condition among the natives.11,12
As the food
moves through the small intestine the nutrients – protein, fats,
carbohydrates, vitamins, and minerals – are absorbed through the
intestinal wall into the bloodstream. Left behind are non-digestible
matters (dietary fibers), colon bacteria and a few dead cells – these
materials soon become the stool. Movement from the right side of the
large intestine to the left side is accomplished by rhythmic
contractions, known as peristalsis.
According to
a law of physics (Laplace’s Law), the pressure within a cylindrical
structure with a given wall tension increases with decreasing radius.13
In other words, contractions at small diameters cause high pressures.
The remnants of digestion on the Western diet produce only a small mass,
and therefore, high pressures.14
Years of elevated pressures produce ruptures in the walls of the
intestine, making balloons, called diverticula.
Blood supply
of the intestine begins on the outer surface, and then these small
vessels dive through the muscular wall to supply the inner surfaces of
the intestine. The weakest part of the wall of the intestine is where
the blood vessels pass through the wall. As a result, the most common
locations of these diverticula are next to blood vessels. Not
surprisingly, one of the most common symptoms of this disease is
bleeding. I have seen the bleeding so severe that the only way to save
the person’s life was to surgically remove the bleeding portion of the
intestine.
When the
diverticula become irritated by the unhealthy remnants of digested food
in the large intestine the openings can close, allowing the fluids to
become stagnant and infected – a condition known as diverticulitis.
This disease is sometimes referred to as “left-sided appendicitis,”
(remember the real appendix is located in the right lower part of the
abdomen), and is usually treated with antibiotics.
A change to
a high fiber diet will greatly reduce the risk of future bleeding and
infection – in other words, people with diverticular disease have much
less trouble after they change to a healthy, high fiber, plant-based
diet.15
However, the diverticula do not disappear with a change in diet.
The Final
Act – Defecation
Matter is
further digested and water is removed during the movement from the right
to left colon. In the final few inches of the large intestine, called
the rectum, the feces accumulate. With adequate filling the rectum
becomes distended, causing reflex contractions, which initiate the
evacuation of the stool into the outside world – properly referred to as
a bowel movement. Unfortunately, life is not so simple for those who
make tiny rock-hard fecal marbles. These little guys simply do not
provide adequate filling to stimulate the rectum. Plus, because of their
slow passage almost all of the water has been removed and they become
dry and hard, thus more difficult to pass. To get them out requires
enormous effort and harmful straining.
Picture a
person seated on the toilet – grunting and groaning. The face is
flushed red from blood pushed up into the head and neck. This is not
the only direction blood is forced by straining. Blood diverted under
pressure into all other body parts causes structural damage. After many
years all this translates into diseases suffered by the majority of
people living on the Western diet.
Hemorrhoids:
Diets low in
fiber cause hemorrhoids by creating high pressure in the veins found in
the very last part of the large intestine, the anus.16,17 A ring of internal veins, the hemorrhoidal veins, provide a
compressible lining which allows the anus to completely close – sealing
the intestine closed – allowing us to act sociably by preventing release
of gasses and stool at inappropriate times and places.
Straining to
pass the small stools causes retrograde pressures in the hemorrhoidal
veins, dilating them. Eventually, after years of straining they are
permanently enlarged and commonly hang out of the end of the anus.
Later stages of hemorrhoid development include the displacement of the
anal muscles toward the outside. Hemorrhoids located higher up are
called internal hemorrhoids; the lower ones are called external
hemorrhoids, the latter are commonly the painful ones.
Since these
are structural changes caused by physical forces they can be expected to
be permanent. Surgery can counter some of this damage with removal of
some of the stretched-out tissue – a hemorrhoidectomy. Surgeries
include sclerotherapy (injection with a caustic substance),
photocoagulation, rubber band ligation, cryotherapy (freezing) and
cutting with a knife and laser. Laser surgery is no less painful and is
more expensive.18
Surgery
should be reserved for those who fail to find comfort from less drastic
means – like topical cleansing and creams, and most importantly, better
food choices. The main symptoms from hemorrhoids are itching, pain, and
bleeding. Sitting in a warm bath (a sitz bath) can provide much
relief. A change to a healthy plant-based diet will do wonders – the
itching, pain, and bleeding usually stop.
You may
wonder why other forms of straining such as lifting or straining to
deliver a baby don’t cause permanent dilation of the hemorrhoid veins.
In all forms of straining, except those associated with bowel movements,
there is a reflex contraction of the anal muscles (sphincter), and this
compensates for the raised pressures in these veins.1
Although
hemorrhoids may have been rare in rural Africa before modernization of the diet, that is not the case today.
Approximately one-fifth of modern black Africans now have these dilated
veins – a direct result of their switch to a modern diet.19
Varicose
Veins:
Straining to
push out small stools causes great retrograde pressures into the veins
of the legs. This pressure is even higher and more damaging because of
our custom of sitting to defecate on high-seated toilets. If you have
traveled to less developed countries, you may have been shocked to find
their toilets are simply holes flush with the ground. To relieve
yourself, you squat. This position bends the legs at the hips and knees
cutting off the veins and preventing pressures created by straining from
being transmitted down into the leg veins – thus protecting them.
Notice that
when you are standing, the distance from the feet to your heart is about
four to five feet. A column of blood this tall would place tremendous
pressures due to the weight of the blood on the veins in the lower leg
and feet. To prevent this, the large veins in the legs have valves that
shut closed to prevent flow of the blood in the direction of the feet.
When we walk the muscles in the legs contract, pushing blood past open
valves towards the heart. However, the valves are one way, preventing
the blood from falling back down toward the feet.
When a
person strains to move those stubborn fecal marbles, the high pressures
dilate the leg veins and stretch out the valves. After years of such
damaging forces, the valves become distorted and incompetent – producing
those well-recognized “blue worms,” that we call varicose veins.16,19
Varicose
veins occur elsewhere: Varicose veins in the scrotum of men are called
varicoceles. In women, this dilation of veins can occur in their vulva
and around their ovaries.
Hiatus
Hernia:
The action
of defecation raises the pressures in the abdominal cavity above those
that are in the chest. The result is that the contents of the abdomen
are pushed up into the chest. The chest and the abdomen are separated
anatomically by a large muscle used for breathing, called the
diaphragm. Three structures pass though the diaphragm – the aorta, vena
cava and esophagus. Only the esophagus is moveable. Straining pushes
the stomach into the natural opening for the esophagus causing the
muscular opening to dilate. A dilated muscle is known as a hernia.
This condition is called a hiatus (or hiatal) hernia.21-22 Eventually
the top portion of the stomach may actually sit in the chest cavity.
Each breath creates negative pressures in the chest that draw acid up
into the esophagus. With the stomach out of its natural position, the
sphincter (lower esophageal sphincter) that functions to close the
opening between the esophagus and stomach when we are not swallowing
becomes incompetent. The result is acids from the stomach can reflux
into the esophagus and up into the mouth and lungs causing esophagitis,
loss of dental enamel, sinusitis, and asthma (see the February 2002
McDougall Newsletter). This condition is referred to as
Gastroesophageal Reflux Disease (GERD).
Surgical
repair can move the stomach back into the abdominal cavity and close the
hernia. However, this operation should be reserved for those who cannot
find relief from a healthy diet, raising the head of their bed and/or
antacids.
Other
Possible Conditions from Straining:
I believe
the following conditions are also due to straining to defecate:
prolapse of the female uterus, spermatocele (dilation of the spermatic
cord), cystocele (prolapse of the female bladder), and rectocele
(prolapse of the rectum).
Treatment
of Damaged Tissues:
Unfortunately, the conditions that are caused by straining are not
returned to normal with a change in diet. But diet will relieve most of
the problems associated with diverticulosis (bleeding and infection),
hemorrhoids (bleeding, pain and itching) and hiatus hernia (heartburn).
Surgery for these conditions and the others discussed (diverticulosis,
varicose veins, and prolapsed uterus) should be reserved for those who
cannot find relief with less drastic measures. I would expect that
changing to a healthy high-fiber, plant-food based diet will slow the
progression of all these conditions, preventing them from becoming
worse.
Rather than
wonder why so much disease is caused by the simple act of moving your
bowels, you should marvel at the strength of your body to withstand
these tissue-wrenching forces for so many years. Today would be a great
day to start reducing the wear and tear on your body – you will be
amazed by how quickly it responds.
References:
1) Ginsberg
A. The fiber Controversy. Dig Dis 1976 Feb, 21:103-112.
2) Taylor
R. Management of constipation. 1. High fibre diets work.
BMJ. 1990 Apr 21;300(6731):1063-4.
3) Burkitt
D. Effect of dietary fibre on stools and the transit-times, and its
role in the causation of disease. Lancet. 1972 Dec
30;2(7792):1408-12.
4) Walker
A. Epidemiology of noninfective intestinal diseases in various ethnic
groups in South Africa. Isr J Med Sci. 1979 Apr;15(4):309-13.
5) Segal I.
Physiological small bowel malabsorption of carbohydrates protects
against large bowel diseases in Africans. J Gastroenterol Hepatol.
2002 Mar;17(3):249-52.
6) Segal
I. Persistent low prevalence of Western digestive diseases in Africa: confounding aetiological factors. Gut. 2001 May;48(5):730-2.
Review.
7) Friedman
GD. Appendectomy, appendicitis, and large bowel cancer.
Cancer Res. 1990 Dec 1;50(23):7549-51.
8) Burkitt
D. The aetiology of appendicitis. Br J Surg. 1971
Sep;58(9):695-9.
9) Walker
A. Appendicitis, fibre intake and bowel behaviour in ethnic groups in
South Africa. Postgrad Med J. 1973 Apr;49(570):243-9.
10) Naaeder
SB. Acute appendicitis and dietary fibre intake. West Afr J Med.
1998 Oct-Dec;17(4):264-7.
11) Simpson
J. Pathogenesis of colonic diverticula. Br J Surg. 2002
May;89(5):546-54.
12)
Painter N. Diverticular disease of the colon, a 20th century problem.
Clin Gastroenterol. 1975 Jan;4(1):3-21.
13)
Young-Fadok T. Epidemiology and pathophysiology of colonic diverticular
disease.
http://www.uptodate.com/patient_info/topicpages/topics/6088F9.asp
14) Aldoori
WH. A prospective study of dietary fiber types and symptomatic
diverticular disease in men. J Nutr. 1998 Apr;128(4):714-9.
15) Leahy
AL. High fiber diet in symptomatic diverticular disease of the colon.
Ann R Coll Surg Engl. 1985 May;67(3):173-4.
16) Burkitt
D. Varicose veins, deep vein thrombosis, and hemorrhoids: epidemiology
and Suggested aetiology. Br Med J. 1972 Jun 3;2(813):556-61.
17) Haas
P. The prevalence of hemorrhoids. Dis
Colon Rectum.
1983 Jul;26(7):435-9.
18)
Brisinda G. How to treat hemorrhoids. Prevention is best;
hemorrhoidectomy needs skilled operators. BMJ. 2000 Sep
9;321(7261):582-3.
19) Ogendo
SW. A study of hemorrhoids as seen at the Kenyatta
National Hospital with special
reference to asymptomatic hemorrhoids.
East Afr Med J.
1991 May;68(5):340-7.
20) Burkitt
D. A deficiency of dietary fiber may be one cause of certain colonic
and venous disorders. Am J Dig Dis. 1976 Feb;21(2):104-8.
21) Sontag
SJ. Defining GERD. Yale J Biol Med. 1999 Mar-Jun;72 (2-3):69-80.
22) Burkitt
DP. Hiatus hernia: is it preventable? Am J Clin Nutr. 1981
Mar;34(3):428-31.
