functional medicine and nutritional genomics - American Association ...

AAPI’S NUTRITION GUIDE TO OPTIMAL HEALTH: USING PRINCIPLES OF FUNCTIONAL MEDICINE AND NUTRITIONAL GENOMICS
Adapted from Crohn's and Colitis Foundation of America, Inc.
http://www.ccfa.org/research/info/aboutcd
Prevalence of Inflammatory Bowel Disease
The Crohn’s and Colitis Foundation of American
(CCFA) reports some alarming statistics. CCFA
estimates that approximately one million Americans
have IBD. This group is split almost evenly between
individuals with Crohn's disease and ulcerative colitis.
Crohn's disease affects both sexes fairly equally.
People of all ages are affected, but the largest group
is adolescents and young adults (ages of 15 to
35). Crohn's disease can occur in the 70+ age
group and in young children. Only 10% of those
affected are age 18 or younger. (4)
A recent review by Head reports that Crohn's disease
predominantly affects Caucasians, with a prevalence
rate of 149 per 100,000. However, recent trends
show that the prevalence of CD and UC is on the
increase with African Americans. IBD is largely a
disease of the industrialized nations, especially the US
and Europe, and is especially in cities and northern
climates. Crohn's disease is prevalent in developed
countries especially white-collar workers with indoor,
sedentary occupations. One theory is that sedentary
jobs delay intestinal transit time, allowing increased
contact between food antigens and the intestinal
mucosa. (11). The incidence of IBD varies by
population. Northern European populations such as the
Irish, Norwegians, Scots and Fins, have a modest risk
compared to those living in lower latitudes (12,13).
The prevalence of IBD in Asians, Arabs, Africans and
African Americans are absent or low (14-18).
Risk Factors
There are several risk factors for CD that range from
adult appendectomy to the use of various substances,
including nicotine (19-21), oral contraceptives,
antibiotics and nonsteroidal anti-inflammatory agents
(NSAIDs). Even second-hand smoke exposure has
(ranging from mild to intense) and cramps
following meals, as well as diarrhea. Fistulas may
form.
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been shown to increase risk for developing CD
(22,23). Other demographic factors such as
economical, educational, geographical and occupational
status can increase the risk of developing CD (24).
Despite these risk factors, Ferguson (25) explains
that ‚IBD is considered a genetic disease‛ as
approximately 20% of people with one form of IBD
have a blood relative also with IBD and 58% of
monozygotic twins share the disease as compared to
4% of dizygotic twins (26,27).
The Immune-Inflammatory Connection
The gastrointestinal tract contains trillions of bacteria
that are ideally in homeostasis with the host immune
system (28). The gut contains most of the immune
cells in the body and engages in a continuous fight
with potentially pathogenic bacteria while leaving
symbiotic bacteria largely unscathed (29). The
presence of antibodies to microbial antigens in CD
supports the theory that one aspect of CD pathology
involves an abnormal immune response to otherwise
normal intestinal flora resulting in inflammation and
impaired intestinal permeability. For example, Crohn’s
disease is characterized by elevations in anti-
Saccharomyces cerevisiae (brewer’s yeast) antibodies
in up to 60% of cases (30). Additionally, levels of
antibodies, such as protein-bound IgG, have been
found in the intestinal mucosa of patients with active
CD to be significantly higher than patients with UC,
irritable bowel syndrome, or non-specific IBD (31).
One theory of immune regulation involves homeostasis
between T-helper 1 (Th1) and T-helper 2 (Th2)
activity (32). "Th1" and "Th2" cells are "important
regulators of the class of immune response." (32)
Alterations in the host gastrointestinal flora can have a
significant influence on the Th1/Th2 balance of the
gastrointestinal immune system (gut-associated
lymphoid tissue or GALT). (33) Sometimes referred
to as the innate immune system or the acquired or