
Unformatted text preview: Lec 19 - Adverse Food Reactions I
Thursday, March 12, 2020 10:13 AM Food Reactions
• Recalls of meat have happened because of E.Coli present in the
meat
○ Intestines of animals get ruptured due to E.Coli
○ Not so much of a problem in cooked meat
• Spinach can be contaminated by E.Coli
○ If the fertilizer has manure in it, and the manure is
contaminated with E.Coli then leads to recalls of spinach
• Cantaloupes can be recalled for E.Coli as well - issue of fertilizer as
well
○ Deaths have occurred from contamination of cantaloupes
• If apple juice is unpasteurized, can harbour E.Coli
• Bottled garlic in water can produce botulin - one of the most toxic
substances that exists
○ Seen in carrot juice as well but very rare
• Can get food poisoning from fish and other seafood
○ Norovirus
○ Inflammation of stomach and intestines
• Perceived risks: no real reaction but people think there is
• Real risks: actual physical effects on the body
• Salem, New Jersey (1820): Robert Gibbon Johnson
○ Tomatoes were not eaten in America because believed they
were thought to be toxic
○ Tomatoes are from the same family as the Belladonna plant,
which is toxic, so people assumed tomatoes were toxic
○ Johnson put an ad in the newspaper that he would eat a
tomato in front of an audience
○ He ate multiple tomatoes and nothing happened to him,
and that is when tomato eating in the USA was born
• Tomatoes have a variety of antioxidants such as lycopene, that
reduces the risk of macular degeneration
• In 1850, English physician Arthur Hasall saw that a steel fork
became coated with copper when he mashed gooseberries that
he had bought for a pie
○ They had been adulterated with copper to make them green
○ Iron reacts with copper compounds to cause oxidation • • •
• reduces the risk of macular degeneration
In 1850, English physician Arthur Hasall saw that a steel fork
became coated with copper when he mashed gooseberries that
he had bought for a pie
○ They had been adulterated with copper to make them green
○ Iron reacts with copper compounds to cause oxidation
In early 1900's, chalk was added to watered down milk
○ Arsenic and boric acid sprinkled on meat and fish to retard
spoilage
○ Lard was added to "extend" butter
Tea was extended by adding indigo
Our food now is closely regulated so we don’t have to worry as
much Toxins
1. Unintentional toxins
○ People overestimate rare risks associated with pesticides
○ People underestimate common risks associated with
microbial contamination
○ Pesticides are a problem when they are improperly used
○ Aldicarb: pesticide used on cucumbers
§ In Dublin, a 15 year old showed up to the emergency
room after getting sick during a soccer game, turned
out he had eaten half a cucumber 30 minutes before
the match
§ The farmer who had used aldicarb on the cucumbers
had not diluted the chemical properly before use, so
there was a high concentration of it present on each
cucumber
§ Symptoms suggested cholinergic poisoning
§ Not the fault of the pesticide, the fault of the farmer
who used it improperly
○ Picnic in the USA: roughly 45 minutes later, 14 became ill
with cramps, nausea, diarrhea, dizziness, sweating, muscle
and eye twitching, and blurred vision
§ The problem was traced to the cabbage salad - added
some ground black pepper, was tested and found to
be 13.7% aldicarb granules, not pepper
§ Most recovered in a few hours but one had to be
given atropine for a slow heart rate and the other
digitalis for an increased and irregular heart beat
§ The common food eaten by those who got sick and
not by those who did not was the cabbage salad § Most recovered in a few hours but one had to be
given atropine for a slow heart rate and the other
digitalis for an increased and irregular heart beat
§ The common food eaten by those who got sick and
not by those who did not was the cabbage salad
○ Mercury in fish: comes from burning coal that gets into the
air and gets washed into the water
§ Can be a problem for pregnant women, because the
developing embryo is most sensitive to toxins pregnant women told to stay away from predator fish
because they contain the highest concentration of
mercury
2. Naturally occurring toxins
○ Coniine: found in hemlock plants, this toxin is lethal
○ Potatoes: sprouting produces solanine, which has the
potential to cause gastric problems
§ Don’t eat green parts on potatoes
○ Mushrooms: the death cap mushroom contains Amanitin,
which will kill humans but rabbits can eat it without issues
§ Amanita muscaria mushroom contains muscarine,
which can also be lethal
○ Molds: some molds can be very toxic
§ Grains are most susceptible to producing toxic mold
§ Mycotoxins found in cereals
§ Aflatoxins (ochratoxin A, patulin, fusarium) are the
most carcinogenic toxins known
§ Corn, barley, peanuts can be contaminated with mold
○ Aged cheese and red wine has tyramine which can give rise
to headaches in people
○ Fish can have histamine, which is a break down product of
proteins - leads to scromboid poisoning which is a reaction
to histamine
§ Happens when fish has not been properly refrigerated
or preserved
§ Histamine causes:
□ Tingling or burning sensation in the mouth
□ Rash on the face and upper body
□ Throbbing headache
□ Hives and itching of skin
□ Nausea, vomiting, diarrhea
§ Treatment is with anti-histamines like Benadryl
○ Ciguatera Poisoning: common in fish like barracuda
§ Happens because these fish eat a certain type of algae
which can be toxic □ Hives and itching of skin
□ Nausea, vomiting, diarrhea
§ Treatment is with anti-histamines like Benadryl
○ Ciguatera Poisoning: common in fish like barracuda
§ Happens because these fish eat a certain type of algae
which can be toxic
§ Within just 3-5 hours, can experience nausea,
vomiting, watery diarrhea, numbness and tingling
about the mouth and extremities
§ In severe cases, can experience muscle pains,
dizziness, and sensations of temperature reversal
where hot things seem cold and cold things seem hot
○ Domoic acid: comes from algae sucking it out of the water
§ 3 people in Canada died from eating muscles
imported from Prince Edward Island that were
contaminated with domoic acid
§ Poisoning causes short term memory loss and
amnesia - but rare
○ Cassava-cyanide: occurs naturally if cassava is not properly
prepared
○ Glycyrrhizin: can be present in licorice root
§ Leads to potassium deficiency, which can cause
paralysis
§ Real licorice root in high doses can be dangerous, not
the licorice you buy in stores
○ Pyrrolizidine Alkaloids: can be present in comfrey tea leaves
3. Body Chemistry Problems
○ Phenylketonuria: genetic condition where people cant
metabolize phenylalanine
§ Phenylalanine is naturally present in aspartame
§ Rare condition, affects 1 in 20,000 births
§ Detected early on in life
○ Lactose intolerance: 70% of the world is lactose intolerant
§ Can occur at any time in life
§ Not a milk allergy - that is an allergy to a protein in
milk, caused by antibodies
§ In lactose intolerance, lactase enzyme is missing in
body so body cannot break down lactose and it goes
to the intestine, where bacteria attack it and body
experiences bloating and diarrhea
§ Breath test used to diagnose lactose intolerance
§ Much of the lactose in yogurt is broken down during
fermentation, so many lactose intolerant people can
still eat yogurt ○ ○ ○ ○ to the intestine, where bacteria attack it and body
experiences bloating and diarrhea
§ Breath test used to diagnose lactose intolerance
§ Much of the lactose in yogurt is broken down during
fermentation, so many lactose intolerant people can
still eat yogurt
§ Can add the lactase enzyme to milk so that people can
digest it
Fructose malabsorption: fructose does not get absorbed
into the blood stream properly in small intestine, goes to
large intestine where bacteria attack it and produces gas
§ Can happen when people eat fruit
§ Hereditary fructose intolerance: problem is that body
cannot process fructose properly because of missing
enzyme called Fructose-1-phosphate aldolase, which
is necessary to absorb fructose
□ Fructose builds up and gives rise to symptoms
of hypoglycemia: nausea, sweating, seizures,
tremors
□ People who suffer from this generally have a
very strong aversion to anything sweet
Sugar alcohol: used widely in processed foods because can't
decay teeth
§ If not processed properly, body will try to flush it out
through diarrhea
Favism: people can suffer from hemolytic anemia, an
abnormal breakdown of red blood cells
§ A deficiency of glucose-6-phosphate dehydrogenase
enzyme when eating fava beans
§ Symptoms of fatigue, shortness of breath, headache,
nausea, vomiting, fever
§ Takes years until proper diagnosis is made
§ Pythagoras suffered from favism
Celiac disease: gluten sensitivity
§ Dr. Samuel Gee (1888): noted that children
sometimes suffer from bloated stomachs, diarrhea,
stunted growth - cause was unknown
§ Dr. Willem. K. Dicke in WWII: Germans cut off food
supply in Holland, including wheat
□ He noticed in 1950 that an unknown constituent
of the diet was damaging the intestines of celiac
patients, the patients got better when they
stopped eating wheat
§ Wheat contains a family of proteins called gluten § § § §
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§ □ He noticed in 1950 that an unknown constituent
of the diet was damaging the intestines of celiac
patients, the patients got better when they
stopped eating wheat
Wheat contains a family of proteins called gluten
□ Gliadin protein: the real problem in celiac
disease, found in wheat, barley, rye, oats
® People who have celiac disease can eat
quinoa because no gliadin in it
® The immune system mistakes gliadin for
an invader and mounts an antibody
attack. This triggers the release of
cytokines which damage the villi
□ Glutenin
Although some people manifest evidence of celiac
disease in the first year of life shortly after the
introduction of gluten into the diet, others experience
the onset of disease manifestations later in life - even
very late in life
It has been hypothesizes that some environmental
factor is likely to be involved in triggering the disease
□ Candidates for this environmental factor are
viral infection, parasite infection, surgery,
childbirth, even the stress of giving up smoking these suggestions are highly speculative
Larger surface area means high absorption
Villi fuse together and inflame - causes celiac disease,
poor absorption of iron, folic acid, calcium, protein
Children: persistent diarrhea and failure to grow can
indicate celiac disease
Adults: unexplained weight loss can indicate celiac
disease
Sometimes get rashes, but the only way to confirm is
diagnosis by endoscopic biopsy
Anti-gliadin antibodies: only about 50% of patients
show damaged villi upon biopsy
Anti-tissue Transglutaminase Test (ANTI-tTG)
Anything made from rice, corn, soy are fine, there is
no gluten
A whole industry created for gluten free products
Incidence is 1 in 100 people, may be linked with Non
Hodgkins Lymphoma
□ Osteoporosis, headaches, behavioural
problems, neurological problems, autism (only a no gluten
§ A whole industry created for gluten free products
§ Incidence is 1 in 100 people, may be linked with Non
Hodgkins Lymphoma
□ Osteoporosis, headaches, behavioural
problems, neurological problems, autism (only a
theory)
§ 1 in 200 people may have "silent celiac disease" - no
overt symptoms on ingesting gluten, but a positive
blood test and biopsy
□ Preventative gluten-free diet is usually
recommended because if they are not put on a
gluten free diet, then eventually they will
develop celiac disease
§ Latent celiac disease = positive blood test but negative
biopsy
□ Usually "watchful warning" given to person, but
no need for gluten free diet
§ Non celiac gluten sensitivity may affect 6-10% of the
population - 6 times as much as celiac disease
○ Allergic reactions
○ Hypoglycemia
4. Idiosyncratic reactions
5. Contamination with microbes ...
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