Food is the basic source of energy for all living beings, stands as a universal
fact. But, sometimes, these food trigger an abnormal immune reaction which
tells us that food can also become harmful to our body. Confusing? Let's
simplify things for a better understanding.
Your body may react differently to certain foodstuffs to which others may
not experience any effect, this unusual reaction can be due to food intolerance.
Symptoms of intolerance may overlap with the food allergy, both may appear
similar but are two different concepts.
Food allergy is an immune reaction that involves IgE antibodies against a
specific food. This reaction is visible within 3-4 hours after the food is
ingested. However, Food intolerance is due to an immune reaction
involving the IgG antibodies. These antibodies form complexes with
the intolerant food that act as immunotoxins, affecting negatively
to our body. They delayed allergic hypertensive reaction, hence,
also named as "delayed food allergy or latent food allergy.
inflammation and chronic diseases may develop due to continuous consumption
of non-tolerated food. Globally, between 20% and 25% individuals suffer from
food intolerance with adults contributing 45% of all.
Know the reason of Food allergy:
In normal condition, the digestive tract epithelium does not allow antigens
to enter it. During the process of inflammation, the antigens gain entry into
the digestive tract and initiate an immune response activating IgG antibodies.
Similarly, during food intolerance, inflammation occurs due to the interaction
between IgG antibodies and food allergens (antigens), this binding damages
the digestive tract layer and allows the food antigens to gain access, thereby
activating more IgG antibodies. Thus, the presence of IgG antibodies against
a specific food allergen direct towards the natural defense reaction against
that pathogen that has entered due to the epithelial barrier damage.
Signs and Indicators of Food Intolerance!
Causes of Food Intolerance :
Some of the common allergens that cause food intolerance are
Milk products, Eges, Peanut, Wheat and Soya. Intolerance can be
explained by either of the below reasons.
Enzymatic Defect: Common example of enzymatic defect is lactose
intolerance. Enzyme betagalactosidase hydrolyzes lactose into
two monosaccharides making them easily available for the body.
During deficiency, lactose reach the colon where the bacteria
degrades the lactose causing disturbances like bloating, abdominal
pain and diarrhea.
Pharmacological Food Intolerance: Vasoactive amines that cause
vasodilation (dilation of blood vessels decreasing blood pressure)
are also a cause of food intolerance. These include dopamine,
histamine, nor-epinephrine, phenylethylamine, serotonin and
tyramine. Food rich in histamine stimulate reactions similar to
the allergic reactions. Under normal conditions, histamine activity
is inactivated by Diaminoxidase (DAO) in the gastrointestinal tract.
If this DAO is damaged then the activity of histamine takes place.
Histaminic effects like erythema, vasodilation, tachycardia,
hypertension, migraine, vomiting and diarrhea can be seen.
Toxins: Food may even contain toxins of the bacterial
or plant origin that provoke intolerance symptoms.
What's the difference between food allergy and an intolerance?
Food allergy refers to an immune reaction against a specific food. The antibodies
produced by the body against specific food (allergen) stimulates an adverse
immune reaction. However, this reaction is spontaneous and the consequences
range from mild to severe life threatening effects. Even a little amount of the
allergic food would stimulate the reaction. On the flip side, food intolerance
involves an unwanted immune reaction involving the IgG antibodies. These
antibodies combine with the intolerant food or the allergen, and form complex
that act as immunotoxins, this in turn affects our body in a negative way.
These immunotoxins cause delayed allergic hypertensive reaction, hence,
food intolerance is also named as "delayed food allergy" or latent food allergy.
On continuous consumption of non-tolerated foods, inflammation and chronic
diseases are developed. Recent studies state that 5% of the adults and 8% of
children suffer from food allergy. Between 20% and 25% individuals globally
suffer from food intolerance with adults contributing 45% of all.
Book Food intolerance profile from Thyrocare
How does a food intolerance test work?
Human serum consists of 70-75 IgG antibodies. They are the basic antibodies
to secondary immune response. Of the four subclasses IgG1, IgG2, IgG3 and
IgG4; IgG3 are capable of activating the complement. These immunoglobulins
are the main form of acquired immunity and produce specific humoral response
In normal condition, the digestive tract epithelium is impermeable
to antigens. During the process of inflammation, the antigens gain entry into the
digestive tract and stimulate an immune response acti antibodies. Likewise,
during food intolerance, inflammation caused due to the interaction between
IgG antibodies and food allergens (antigens) continue to damage the membrane
and increase the permeability to food antigens, thereby activating more IgG
antibodies. Thus, the presence of IgG antibodies against a specific food allergen
direct towards the natural defense reaction against that pathogen that has
entered due to the epithelial barrier damage.
In a study conducted among the irritable bowel syndrome and dyspepsia,
the patient's body had a significant high levels of IgG antibody against the
food antigens than the normal individuals. Immune response to specific food
can even be related with the dietary habits and other factors,
What is the root cause of food intolerance?
Food allergens vary from person to person. The same food
They are that may be intolerant to an individual can be widely
tolerated by the general population. Some of the common
allergens are Milk products, Eggs, Peanut, Wheat and
Soya. Intolerance can be explained by either of the
reasons like enzymatic defect toxins histamine and salicylates
those that cannot be classified in any of the above are called
as undefined food intolerance
The food intolerance symptoms Toxins: Food may even contain
toxins of the bacterial generally manifest in the gastrointestinal
tract. The most or plant origin that provoke intolerance symptoms.
common example of enzymatic defect is lactose intolerance.
It arises due to the deficiency of the enzyme beta-galactosidase
that aids in the hydrolysis of lactose into two monosachharides
making them easily available to body. In case of deficiency,
lactose cannot be hydrolyzed and used up rather they reach the colon
where the bacteria degrades it. This results in disturbances like
bloating, abdominal pain and diarrhea The prevalence of lactose
intolerance is about 60,23% in the population .
Pharmacological food intolerance:
Vasoactiveamines that cause vasodilation (dilation of blood
vessels decreasing blood pressure) are also a cause of food
intolerance These include dopamine, histamine, norepinephrine,
phenylethylamine, serotonin and tyramine Histamine is a diamine
and a prominent mediator of allergies. Food rich in histamine stimulate
reactions similar to the allergic reactions. Histamine is inactivated
by the Di-Aminoxidase (DAO) in the gastrointestinal tract rendering many
people unaffected . other diamines ar drugs damage the activity of DAO
thus triggering intoxication symptoms ,the similar symptoms are likely to
appear after consuming spoiled fish. High levels of histamine are found in
fish, two other diamines produced in spoiled fish are- putrescine and cadaverine
They are responsible for hindering the DAO activity followed by histaminic effect
like erythema vasodilation tachycardia, hypertension, migraine, vomiting and
diarrhea. It is very uncommon that the symptoms last for a longer time and result
in severe consequences unless associated with comorbidities like coronary artery
Food may even contain toxins of the bacterial or plant origin that provoke intolerance
Intolerance due to food additive reactions can be termed as undefined intolerance .
generall, additives used in food production are limited to their legal dosage, and
are Generally Recognized as safe (GRAS) products. some individuals may still
show intolerance glutamate and some food colorings intolerance is seen via the
symptoms such as asthma, rhinitils, urticaria, itchiness, and migraines. The exact
mechanisms of these intolerances are yet to be understood completely .
Food intolerance Types
Food intolerance can be of different types. Few of them are mentioned below:
- Lactose intolerance
- Wheat intolerance
- Gluten intolerance
- Caffeine intolerance
- Histamine, present in mushrooms, pickles and cured food
- Additives such as artificial sweetners, coloring or flavorings
Diagnosis between food intolerance and food allergy
Diagnosis between food intolerance and food allergy
remains a challenge as most of the symptoms overlap
Both come with an advantage that aids in diagnosing
food intolerance is shown in delayed manner whereas
allergic reactions are seen immediatey. Further, to rule
out allergy, a doctor may suggest for askin test or blood tests. The presence of IgG antibodies is checked for intolerance,
whereas for allergy, the presence of IgE antibodies
At Thyrocare, we use state-of-art Microarray technology
which aids in detecting food specific IgG antibodies. It is a
highly sensitive and accurate technique that detects
allergens (food specific IgG antibodies) to over 217
commonly eaten foods. This helps in the identifying the
foodstuffs that cause intolerance symptoms and guide in
designing the elimination diet (food that needs to be avoided).
What is an Elimination Diet?
A food intolerance test would aid in identifwing the food
causing adverse symptoms. Based on food intolerance
testing elimination diets are advised which include food
causing an adverse reaction .Eliminating the food for a
short duration of time can help in coping up whit the
condition .After the particular time, showly addition
of the food can be done so as to see for any kind af
intolerance still existing .
Elimination diet is recommended in gastroenterology
(e.g. irritable bowel syndrome, Crohn's disease ulcerative colitis),
rheumatology (e.g. rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis),
dermatology (atopic dermatitis, psoriasis) and immunology (autoimmune disorder including
Food intolerance Test
The best treatment option for intolerance lies in eliminating the food or reducing
their quantity. But to plan out the diet, testing is a must. Taking supplements
that help in digestion can also be an option for dealing with intolerance. Fasting
from the food allergen is also an ideal treatment option.
Elimination of allergen may at times create nutritional deficiencies,
to overcome them additional supplements or vitamins can be used.
One of the major problem that remains is the hidden ingredients
in the commercial foods that may be an allergen. Thus advised to
check the food labels before consuming it .