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The Effects of Antibiotics on Food Intolerances
Food intolerances can be life long burdens many Americans have to deal with.
According to an article by the U.S. Department of Health and Human Services, nearly 50
million Americans are troubled with lactose intolerance, just to name one (“Lactose
Intolerance”). To put this into perspective, the US Census Bureau reports that in 2014 just
over 38 million Americans were living in California, the most populated state that year
(“U.S. and World Population Clock”). So hypothetically, all of California and the near 12
million living in Pennsylvania l could all have been taxed with lactose intolerance ("Florida
Passes New York to Become Nation's Third Most Populous State."). Another example of a
food intolerance is a non-celiac disease gluten intolerance, which the National Foundation
for Celiac Awareness reports 18 million Americans are living with ("Non-Celiac Gluten
Sensitivity"). America’s current population is just over 322 million, so the percentage of
Americans who have gluten intolerances would be just near 5%, which is what the US
Bureau of Labor and Statistics reports the national unemployment rate is as of September
of 2015 ("Databases, Tables & Calculators by Subject"). Food intolerances such as lactose
and gluten intolerances affect a great deal of Americans, and have the potential to affect
more people daily.
As something that can affect food intolerances, the bacteria in the gastrointestinal
tract and digestive system play a role in the digestion and breaking down of food. The
gastrointestinal (GI) tract and digestive system includes the mouth, esophagus, stomach,
small intestine, large intestine, liver, pancreas, and gallbladder. The 4th edition of Medical
Microbiology reports “The intestinal micro flora may prevent infection by interfering with
pathogens . . . upset the balance of the normal flora can favor both infection by exogenous
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pathogens and overgrowth by endogenous pathogens” (Gorbach). If these essential
bacteria are harmed, the consequences can be detrimental to the health of the individual.
Published in the National Center for Biotechnology Information, Doctors Ann O’Hara and
Fergus Shanahan discuss that without gut flora, or bacteria, people are significantly more
susceptible to infections and diseases, have a decreased digestive enzyme activity, and a
thinner muscle wall (O’Hara and Shanahan). Without the friendly gut bacteria that are
currently in the gastrointestinal tract aiding in the detection of other bacterial infections,
the digestive tract would be under attack more than it may already be. The layers of the
intestinal lining may be jeopardized as well as surrounding organs, such as the colon or
liver. According to osteopathic medical doctor, David Williams, digestive enzymes “function
like solvents that break down foods into the components that allow them to be absorbed
and used by the body” (Williams). So without these digestive enzymes, the digestive system
will have a more difficult time breaking down components of foods ingested, potentially
leading to a hindrance in the absorption of nutrients from food.
Dysbiosis, or bacterial imbalance can have several causes such as stress, diet and
antibiotics. Stress in the gastrointestinal tract can lead to decreases in the diversity in
bacteria. In a study conducted by Bailey and Coe, young monkeys were tested for changes
in their gastrointestinal bacteria after being separated from their mothers. The results after
20 days show a decrease in the concentration of certain bacteria (Hawrelak). The study
shows the connection between psychological stress and gastrointestinal gut bacteria
diversity. Diet can also change the composition of gut bacteria. Unhealthy diets like those
that are high in fat or high in sugar have negative effects on gut bacteria. According to a
study done on mice by Turnbaugh, Backhed, Fulton, and Gordon, ten mice were put on the
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same diet then were all given the same types of bacteria, after four weeks five mice were
switched to a “western diet” which is a high fat and sugar diet. The results show the mice
on the western diet had a dramatic decrease in diversity because one type of bacteria that
does not have a cell wall barrier (Turnbaugh et al). In these mice, the abundance of bacteria
reduced drastically, because of the increase in the amount of a specific type of bacteria that
is weak and susceptible to toxins.
As previously mentioned, antibiotics are something that can cause imbalances in
gastrointestinal bacteria. The imbalance caused by antibiotics has the potential to cause
food intolerances. Antibiotic use has been suggested to be helpful in the termination of
bacterial and parasitic infections and invasions; antibiotics do have accessory effects that
may not be quite as helpful, like harming the good bacteria. The purpose of taking
antibiotics is to kill off the harmful bacteria or parasite that is causing an infection or
disease, but what antibiotics do not do is characterize the essential bacteria from the
destructive bacteria. As previously mentioned, the bacteria in the digestive tract
specifically play a role in the digestion and absorption of food. Irregularities can arise when
bacteria are not functioning like they are supposed to. Antibiotics, while helpful, are one of
the several causes of intestinal flora imbalance, and while there are ways to restore
balance, such as with the use of probiotics, bone broth, and diet changes, the brief time of
imbalance can lead to digestive issues such as this disruption can lead to digestive issues
like food intolerances.
While the terms have been used interchangeably, there is a clear distinction
between food allergies and food intolerances. True food allergies are immune system
responses, while food intolerances are digestive system responses. During a food allergy,
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the immune system sends out a cell, called an immunoglobulin, which is sent by the
immune system to combat bacteria that have been triggered as harmful; immunoglobulin E,
or IgE is the specific immunoglobulin sent out during food allergies. After these IgE cells
are sent out into the blood stream, hormones are secreted, and according to Charles
Janeway, Paul Travers, Mark Walport and colleagues who wrote Immunobiology, symptoms
can vary from itchy, watery eyes, sneezing, and hives, to full systemic anaphylaxis (Janeway
et al). The chain reaction the immune system sends can have various ways of presenting
itself in the outward appearance, some of which may resemble a food intolerance, but still
originated with the immune system. The other noteworthy difference is the anaphylactic
reaction. The National Institute of Health (NIH) defines anaphylaxis as “a sudden and
severe allergic reaction that occurs within minutes of exposure. Immediate medical
attention is needed for this condition. Without treatment, anaphylaxis can get worse very
quickly and lead to death within 15 minutes” ("Allergic Reactions: MedlinePlus Medical
Encyclopedia."). Several full blown allergic reactions can be fatal, as the NIH states, and is
typically more severe than a reaction to a food intolerance.
As previously mentioned, the symptoms of food allergies can range from stomach
pain or nausea to full on anaphylaxis. Symptoms can vary depending on how severely
allergic the individual is and the level of exposure to the allergen. Research at the
University of Nebraska also adds that symptom severity can be dependent on the “amount
of food ingested, the tissue receptors that are affected, and the length of time since the
previous exposure” (“Symptoms and Severity”). Once the food allergen is ingested, an
individual might begin to feel the throat tighten up or might even begin to have swelling in
the lips and face. If the individual has more severe food allergies the trouble breathing
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might be the beginning stage of an anaphylactic shock. According to the National Institute
of Health, anaphylaxis is the immune system responding to an allergen and can affect ones
skin, nose, throat, chest, heart and nervous system (“Anaphylaxis”). This severe allergic
reaction to food affects several organ systems, which is part of the reason anaphylaxis can
be so fatal. Medical attention must be sought after immediately when someone is in
anaphylactic shock to prevent the symptoms from worsening and to ensure the safety of
the individual.
In contrast to food allergies, which are immune reactions, food intolerances are
responses of the digestive system and are caused by gastrointestinal irregularities, rather
than an immune system response to a cell deemed fatal. According to the American
Academy of Allergy Asthma and Immunology (AAAAI), a food intolerance happens when “a
person has difficulty digesting a particular food. This can lead to symptoms such as hives,
intestinal gas, abdominal pain or diarrhea” (“Food Intolerances Defined”). There could be
several causes that could lead to having a difficulty digesting food, such as food poisoning,
natural histamine in foods, additives in foods, enzyme deficiencies, and bacterial
disturbances. According to an interview with Dr. Art Ayer, writer Eric Hunter reports that,
“food intolerance is based on missing bacteria in the gut rather than inadequacy of human
enzymes . . .” (Hunter). Slight changes in bacteria can cause the irregularities in digestion,
which not only did Dr. Ayer claim was harmful towards the development of food
intolerances, but can also he harmful in the way nutrients are absorbed and released as
waste. Previous knowledge in food intolerance believes enzyme deficiencies are the leading
cause of food intolerances, but as Dr. Ayer shows, research is shifting this accepted
observation.
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Similar to the mild food allergy symptoms, symptoms or signs of food intolerances
can be characterized by nausea, hives, chest pain, and shortness of breath. However, the
difference in reactions between food allergies and food intolerances is the reaction time
and the severity of reactions. Since the immune system is not the organ system that is
reacting when it comes to food intolerances, reactions are often more delayed and last
longer than in the case of food allergies. Because the digestive system has to rid the body of
this food it is struggling to digest, the symptoms may last even longer until the food is
completely expelled from the body. Since food intolerances do not trigger the immune
system, the individual with the intolerance may be able to have small amounts of the food,
and may only experience symptoms when the digestive system is not able to handle the
unlimited amount of food. Food intolerances do not result in anaphylaxis and are not fatal,
but individuals may still experience harsh stomach pains.
Bacterial imbalances are the cause of several cases of food intolerances, but enzyme
deficiencies are what cause the greatest number of food intolerances. Having an
intolerance to lactose is usually the result of lacking the enzyme that breaks down lactose
or the body doesn’t produce adequate amounts of the enzyme, which is called lactase.
According to the National Institute of Health, the most common form of a lactase deficiency
is primary lactase deficiency which is when “lactase production declines over time . . . some
people inherit genes from their parents that cause a primary lactase deficiency” ("Lactose
Intolerance," Lactose Intolerance). Instead of the continuing production of lactase, the body
starts producing fewer and fewer enzymes, which raises the intolerance levels to lactose.
As the intolerance levels rise, symptoms like diarrhea, bloating, nausea and stomach pains
can become more severe especially if the lactose product was consumed in a large quantity.
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As briefly mentioned, bacterial imbalances can cause food intolerances, and one of
the causes of bacterial imbalances is the use of antibiotics. Antibiotics are a prescribed
medication used to destroy and prevent growth of bacteria, and can work very well when
diminishing the invasive bacteria; however, the antibiotics cannot discern the harmful
bacteria from the helpful bacteria, and ends up destroying both. In a report published in the
journal Elsevier, Doctor Stig Bengmark exposes that “antibiotic treatment will dramatically
destroy intestinal homeostasis and introduce changes that affect almost 90% of the
functions of microbiota” (Bengmark). Since the majority of gut bacteria are jeopardized, the
susceptibility for the development of food intolerances greatly increases. This increase has
the potential to be short lived, as antibiotics do not permanently destroy bacteria; with
time some of the essential microbiota will recolonize. While some may become a presence
in the gut again, some bacteria may not reappear again in the digestive system. An
experiment conducted by Doctor Les Dethlefsen observing the effects antibiotics have on
human gut microbiota by rRNA, Dethlefsen found that the antibiotic ciprofloxacin
decreased the diversity and composition of bacteria in the gut (Dethlefsen et al). In this
study, the specific antibiotic ciprofloxacin, which is often used to treat bronchitis, urinary
tract infections, and staph infections among other infections, was shown that the bacteria
in the GI tract are vulnerable to antibiotics even when the infection may not be related to
the digestive system or related organs.
The effect antibiotics have on bacterial imbalances can be crucial, but not everyone
develops food intolerances as a result of antibiotics. Due to bacteria being live organisms,
they can adapt to survive, which is what happens with antibiotics. The good and bad
bacteria can change and become resistant to antibiotics for repeat users of a specific
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antibiotic. This is not ideal in terms of the harmful bacteria, but when discussing the helpful
bacteria that live in our gastrointestinal tract, it can be advantageous. For individuals who
often have bacterial infections or diseases, helpful bacteria can become resistant and the
colonies and diversity left it the gut after a dosage will not end up being as damaged as the
individuals with nonresistant bacteria.
Resistant bacteria can be a reason some people do not experience food intolerances
after using antibiotics, but it may be a result of the frequency an individual uses antibiotics.
Someone who rarely uses antibiotics may be more likely to develop an intolerance that is a
result of a bacterial imbalance because the helpful bacteria in their digestive system has
not grown to be resistant. However, there are individuals who over use antibiotics and
there are people who get bacterial infections and diseases so often that they need
antibiotics frequently. Some individuals tend to take antibiotics for viral infections, which
builds up bacterial resistance for when they are actually prescribed antibiotics in the
future. Similarly, there are individuals who have bacterial infections frequently enough that
the bacteria have become resistant causing more extensive antibiotics and medicines to be
used. For both over users and frequently prescribed users, the bacteria causing more
extensive and expensive medicines and solutions to rid the body of the resistant bacteria
that is causing the infection build up resistance.
As briefly mentioned, some bacteria do, in fact, recolonize, and there are different
dietary measures and perspectives that can be taken to aid in this process. First, there is
the paleo-diet, also referred to as the caveman diet, consists of only eating foods that
primitive man would have been exposed to. For example, an article on paleoleap.com
reports fifteen rules on eating paleo, to include keeping a high fat and low carbohydrate
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diet; eating fruits, vegetables, and nuts; but to eliminate all grains such as wheat, corn,
brown rice, and oats (“Paleo Diet 101”). The purpose of this diet is to eat clean and rid
your diet of processed food. This clean eating provides the opportunity to rid the digestive
system of any toxins and reduce the amount of dairy and sugar consumption. The paleo
diet also eliminates additives and preservatives that processed foods add to a diet, as an
article in Natural Family Today describes ("5 Ways to Heal Your Gut After Antibiotics.").
Another means to restoring bacteria colonies in the digestive system is by taking
probiotics. An article on the National Institute of Health website defines probiotics as
“Probiotics are live microorganisms that are intended to have health benefits”
(“Probiotics”). Adding these helpful bacteria to a post-antibiotics diet can help expedite the
process of bacteria re-expansion. Since probiotics are live bacteria, adding it to ones diet
can also aid in the digestion of food, as well as add more diversity to the bacteria left in the
gut after a round of antibiotics. An article on WebMD discusses the different ways
probiotics can be taken, which include: in the form of a supplement, foods such as yogurt,
fermented foods like sauerkraut or pickles, and yeast (DiLonardo). It is important that
probiotics used specifically for replenishing after a series of antibiotics is taken once the
dosage of antibiotics has been completed or else the antibiotics have the potential to kill
those bacteria taken in from the probiotics. Since probiotics, such as some yogurts, provide
the digestive system with more helpful bacteria, there is a reduced risk in developing a
food intolerance as a result of antibiotics.
A final way to help reduce the post-antibiotic bacteria deficit would be adding bone
broth to ones diet. Bone broths are a recommendation made by several alternative
medicine websites and doctors that use medicines as minimally as possible. According to
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Natural Family Today, bone broth helps in the restoration of the mucosal lining in the
intestines after antibiotics ("5 Ways to Heal Your Gut After Antibiotics."). The mucosal layer
in the intestines is important for absorption of water and electrolytes. Without this
absorption there would be a lack in electrolyte uptake, which is important for the pH of
blood, and there would be serious changes in the consistency of stool in humans. The
mucosal layer in the intestines also has the potential to become damaged by having food
intolerances. In an experiment conducted by Doctors Carroccio, Scalici, Maresi, and
colleagues, fifty-two patients with chronic constipation were set up with either a cow’s milk
free diet or an oligoantigenic diet, which is a diet that has the least risk for causing an
allergic reaction, for four weeks; the researchers concluded that the subjects with food
intolerances had a much higher frequency of mucosal layer deterioration (Carroccio et al).
So if a patient, who already has a food intolerance, then takes antibiotics the mucosal layers
are being corroded even more than they already are, conversely, if a patient does not have
a preexisting food intolerance, the course of the antibiotics begins to wear down the
mucosal layer. As mentioned, bone broth can help restore this erosion with the gelatin that
is contained in bone.
In short, the use of antibiotics without any follow up use of a probiotic has
the potential to be a main factor in the development of food intolerances. The dietary
adjustments that can be made during a dosage of antibiotics can be crucial to avoiding
some symptoms of food intolerances, which may include: nausea, stomach pains and
discomfort, diarrhea and vomiting. As stated, necessary antibiotic use paired with
probiotics and clean eating can provide the intestines and the rest of the digestive system
with the helpful bacteria that aids in the breaking down and absorption of food and
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nutrients. These few changes can save Americans the agony of dealing with more
discomfort and symptoms on top of the reason for the antibiotic use.
Since antibiotics can affect the bacteria in the gastrointestinal tract, physicians
should recommend dietary changes patients could consider making during the course of
the antibiotics. Physicians making these suggestions could help in the prevention or
minimization in the development of digestive complications. A personal physician
recommendation might also influence Americans more than impersonal television ad
marketing based on the professional knowledge of physicians. Physicians may make verbal
suggestions, or may even pair up with the pharmacist that the patient receives the
antibiotics from and deliver the suggested food and meal adjustments through that setting.
Physicians and pharmacists could also team up to create general meal plan guidelines and
templates for patients, so patients can have an idea of changes and modifications to make
while taking the prescription of antibiotics. This change may be impractical based on the
resources a physician might have, or even the type of pharmacy a patient gets prescriptions
from, but even if the physician is not fully forthcoming with all the approaches to handle
taking antibiotics, starting the dialogue with the primary care physician can be helpful to
find more information as well as helpful in building a relationship for future visits.
Another partnership that can develop and use the information provided could be
marketing departments of corporations that sell probiotics and medical researchers.
Knowing that probiotics, such as those found in yogurt can be an advantageous marketing
tool for companies. A medical research team could conduct studies comparing different
probiotic yogurts and how they effective they are in diversifying the bacteria in the gut of
the consumers. A research team could also compare the effectiveness of a probiotic yogurt
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versus a probiotic supplement and how well they achieved the goal of restoring bacteria
after a course of antibiotics. This information can help a yogurt or supplement company
target a specific group of consumers in a new campaign. This relationship between medical
researchers and yogurt corporations can also allow medical research to discover more
about the benefits of probiotics and look into how different types of yogurt, such as Greek,
nonfat, or Swiss can have different affects on the growth of friendly bacteria in the
intestines. This relationship could also have drawbacks. The financial expenditures a
partnership like this might be great, but it could also lead to an increase in profits. The
medical researchers would also have to be weary of any biases towards the effect of the
corporation’s probiotic on the bacteria richness in the gut, but with a maintained integrity
on both ends, medical research might be a marketing tool that could improve yogurt sales,
as well as improve the gut health of many Americans.
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