Topics in nutrition and food science.

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Topics in nutrition and food science.

• Dr M. Altamimi

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Characteristics of Modern life

• Urbanisation
• Ready to eat food, fast food and processed food.
• High calories (fat and carbohydrate) low fibre.
• Low in vitamins and minerals.
• Packaging. Not natural preservation.
• Refrigeration and freezing.
• Less physical activity.

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• Office based jobs.
• Chronic diseases, obesity etc.
• Aging, people live longer.

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• Diet together with physical exercise plays a
  major role when we try to prevent or postpone the
  onset of chronic conditions such as the metabolic
  syndrome.
• The food industry has already reacted to this
  challenge and a large number of products have
  been either reformulated or re-positioned to meet
  the current need for healthier foods.

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WHO

• Chronic diseases are diseases of long duration
  and generally slow progression. Chronic diseases
  are by far the leading cause of mortality in the
  world, representing 63 of all deaths. 36 million
  people died from chronic disease in 2008.

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Noncommunicable diseases

• Cardiovascular diseases account for most NCD
  deaths, or 17 million people annually, followed
  by cancer (7.6 million), respiratory disease (4.2
  million), and diabetes (1.3 million). These four
  groups of diseases account for around 80 of all
  NCD deaths, and share four common risk factors
• tobacco use
• physical inactivity
• the harmful use of alcohol and
• poor diets.

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Bad habits
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Stages of life and R F

• In the uterus
• intrauterine growth retardation (IUGR)
• premature delivery of a normal growth for
  gestational age fetus
• over nutrition in utero
• Intergenerational factors.

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• Infancy
• Retarded growth in infancy can be a reflected in
  a failure to gain weight and a failure to gain
  height. Both retarded growth and excessive weight
  or height gain can be factors in later incidence
  of chronic disease. Such as CVD
• There is increasing evidence that among term and
  pre-term infants, breastfeeding is associated
  with significantly lower blood pressure levels in
  childhood.
• Consumption of formula instead of breast milk in
  infancy has also been shown to increase diastolic
  and mean arterial blood pressure in later life.
  Obesity

(type 1 diabetes, coeliac disease, some childhood
cancers, inflammatory bowel disease) have also
been associated with infant feeding on
breast-milk substitutes and short-term
breastfeeding
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• Childhood
• low growth in childhood and an increased risk of
  CHD has been described, irrespective of size at
  birth.
• Relative weight in adulthood and weight gain have
  been found to be associated with increased risk
  of cancer of the breast, colon, rectum, prostate
  and other sites.
• Higher blood pressure in childhood (in
  combination with other risk factors) causes
  target organ and anatomical changes that are
  associated with cardiovascular risk, including
  reduction in artery elasticity.
• High blood pressure in children is strongly
  associated with obesity,

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• Most chronic diseases are present at later period
  of life - the result of interactions between
  multiple disease processes as well as more
  general losses in physiological functions (due to
  risk factors)
• lack of oxygen and adapted metabolism.

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Angiogenesis

• Angiogenesis is a process of new blood vessel
  growth that occurs in the human body at specific
  times in development and growth.
• Although crucial for embryonic development and
  wound healing, angiogenesis also contributes to
  disease, such as in the growth of solid tumors,
  chronic inflammation, atherosclerosis, ischemia,
  and diabetic retinopathy.

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Inducers

• A number of inducers of angiogenesis have been
  identified, there is an emerging concept that
  reactive oxygen species (ROS such as )

superoxide anion O2- hydroxyl radical (OH-),
lipid radical (LOO-), peroxy radicals (XOO-)
and singlet oxygen (O-).
Free radicals
ROS are products of mitochondrial respiration
(energy production).
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Dietary sources of ROS

• High fat diet and deep fries
• High sucrose (or refined carbohydrates )diet
• Protein sugar in high temperature (glycation)
• Low fruit and veg. diet
• Low vitamin and mineral diet (antioxidant).

Life style stress, pollution, smoking and low
activity.
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Golden rule

• More free radicals chronic diseases faster
  aging.
• Less free radicals healthier body.

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How to slow down generation of Free radicals?

• Homework.

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Comparison
B
A
Distance 10,000 km Fuel consumption 50,000
liter
Distance 200, 000 km Fuel consumption 1000,000
liter
Waste? Maintenance? Type of fuel?
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The challenges for nutrition in the twenty-first
century

• 1. Application of new scientific knowledge in
  nutrition.
• 2. Improved scientific knowledge on dietdisease
  relationships.
• 3. Exponential increase of health-care costs.
• 4. Increase in life expectancy.
• 5. Consumer awareness of nutrition and health
  relationships.
• 6. Progress in food technology.

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Functional foods
History
Japan 1940-1950 economical food with minimal
nutrients. 1950-1970 safe and hygienic food with
better taste. 1970- 1980 convenient food. Easy
or precooked food. 1980- Food for specific
health use (foshu). 1990 - Functional food.
(project)
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• The project also proposed for the first time the
  new concept of functional food and defined food
  functions as primary (nutritional), secondary
  (sensory) and tertiary (physiological). Food with
  physiological functions was of particular
  interest, because such food would be useful for
  improving the health of the general public

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Definition

• no simple, universally accepted definition of
  functional food exists. Examples
• food and drink products derived from naturally
  occurring substances consumed as part of the
  daily diet and possessing particular
  physiological benefits when ingested.
• food derived from naturally occurring substances
  that can and should be consumed as part of the
  daily diet and that serve to regulate or
  otherwise affect a particular body process when
  ingested.
• food similar in appearance to conventional food,
  which is consumed as part of a usual diet and has
  demonstrated physiological benefit and/or reduces
  the risk of chronic disease beyond basic
  nutritional functions.

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The main aspects of this working definition are

• the food nature of functional food that is not a
  pill, a capsule or any form of dietary
  supplement
• the demonstration of the effects to the
  satisfaction of the scientific community
• the beneficial effects on body functions, beyond
  adequate nutritional effects, that are relevant
  to improved state of health and well-being and/or
  reduction of risk (not prevention) of disease
• the consumption as part of a normal food pattern.

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F F Science

• By reference to the new concepts in nutrition
  outlined above, it is the role of functional food
  science to stimulate research and development of
  functional foods

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Claim promise of improvement

• Disease reduction claims meaning
• consumers have difficulties to differentiate
  between the terms disease risk reduction and
  prevention of diseases.

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How to write a claim
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EFFECT OF FOOD PROCESSING ON FUNCTIONALITY OF
FOODS
In foods containing vastly different
phytochemicals, the physiological activity due to
food processing may be a result of more than one
mechanism. Consequently, there may be a
decrease, increase, or a slight change in the
content and functionality of phytochemicals.
No/slight effect carotenoids comprising of
b-carotene and lycopene are generally stable to
heat treatments encountered in blanching,
cooking, and pasteurization/sterilization.
Interactions between polyphenols and ascorbic
acid may slow the degradation of the latter
during storage.
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Decrease in content and activity of
phytochemicals a classic example is that of the
technological indicator, ascorbic acid, which
is by far the most sensitive nutrient, and can be
damaged during most treatments. Chemical and/or
enzymatic oxidations are reported to decrease the
antioxidant efficacy of polyphenolics, while
leaching into the cooking water is mainly
responsible for loss of folates.
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Heat processing of Brassica vegetables of the
Cruciferae family greatly reduces their
functionality . Manufacture of black tea causes
a higher degree of enzymatic aerobic oxidation of
flavonoids, resulting in lower antioxidant
activity. Some processing operations such as
peeling and juice clarification can remove the
polyphenolics .
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Increase in content and activity of
phytochemicals partially oxidized
polyphenolics that result during food processing,
have been recently shown to exhibit higher
antioxidant activity than the corresponding
non-oxidized forms, due to increased ability to
donate a hydrogen atom
A moderate increase in carotenoid bioavailability
and enhanced phytochemical nutrient function in
cereal processing
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Examples of functional ingredients
Vitamin antioxidant mineral premixes tomato
powder, garlic powder, onion powder, spice mixes
amino acids, chitosan Omega-3-fatty acids (fish
and flax seed) whey protein powder Guarana
extract, G. biloba extract, ginseng extract,
rosemary probiotics natural antioxidants (from
tea) shield liquid antioxidants vegetable
peptones
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essential fatty acids concentrates performance
proteins natural fruit based flowering
compounds natural colours total extracts of
medicinal plants antioxidants soy ingredient,
soy proteins, soy protein hydrolysate soya
protein isolate concentrate super critical
extracts of spices and herbs glutamine
peptides lactoferrin, milk calcium lycopene,
garcinia, raw herbs whey protein concentrate
wheat fiber, b-carotene A. vera gel powder.
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Risk factor or state Design a Functional Food
CVD
osteoporosis
diabetes
Irritable bowl syndrome (IBD)
Pregnant woman
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OXIDATIVE STRESS AND ROS

• Oxidative stress rusting of tissues.
• Oxidative stress is imposed on the body s cells
  when the level of ROS outweighs the reducing
  capacity of antioxidant and antioxidative stress
  mechanisms

ROS
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Sources of ROS

• Endogenous sources of ROS
• tissue injury
• via auto - oxidation reactions in the presence of
  transition metal ions. Fe 2 or Cu
• during cytochrome P450 cycling.
• at inflammatory sites by activated and
  phagocytes.

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• Exogenous sources of ROS
• Exposure to ultraviolet (UV) radiation.
• Overexercise.
• Extrinsic xenobiotics found in tobacco smoke.
• Heavy metals.
• Organic pesticides.
• Lipid hydroperoxides in particular are
  potentially toxic products of peroxidized
  polyunsaturated fatty acids (PUFAs) derived from
  dietary fats.
• Compounds present in foods such as transition
  metal ions, heme from meats, isoprostanes,
  additives, lipids,

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DEFENSE SYSTEMS
Endogenous antioxidants and antioxidative defenses

• Glutathione ( GSH )
• tripeptide of ? glutamylcysteinylglycine.
• directly scavenge free radicals or act as a
  substrate.
• GSH present in foods and secreted in the bile can
  contribute to GSH concentrations in the
  intestinal lumen.

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• Antioxidative stress enzymes
• glutathione peroxidase (GPx).
• glutathione S -transferase ( GST ).
• Catalase
• Additional antioxidants
• uric acid.
• bilirubin - bound albumin, and albumin itself.
• Histidine - containing peptides such as
  carnosine.
• Melatonin.
• Amino acids, peptides, and even proteins.
• Se, Zn, Cu, Mn and riboflavin can all have
  co-factor functions for one of the above enzymes.

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Phytochemicals with antioxidant activities

• Polyphenols
• 5000 polyphenols and over 2000 flavonoids having
  been identified.
• Phenolic acids, Flavonoids, Lignans

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• Amides
• strong antioxidants capsaicinoids in chili
  peppers.
• Carotenoids
• Lycopene, ß carotene, xanthophylls such as
  zeaxanthin.

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Mechanism of action

• direct radical scavenging
• (2) downregulation of radical production
• (3) elimination of radical precursors
• (4) metal chelation
• (5) Inhibition of xanthine oxidase
• (6) elevation of endogenous antioxidants.

Curcumin and flavonoids have been shown to
upregulate intracellular GSH synthesis and
increase antioxidant enzyme activities
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METABOLISM AND BIOAVAILABILITY OF FLAVONOIDS

• The extent of absorption of dietary polyphenols
  in the small intestine is relatively small.
• Bacterial enzymes may catalyze several reactions.
• Anthocyanins were found in the cerebellum,
  cortex, hippocampus. important for learning and
  memory.

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Antioxidant and C D

• CVD
• Antioxidant prevent LL oxidation.
• Cancer
• Block activation to carcinogens.
• DNA repair.
• Inhibit the formation and growth of tumors.

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Dietary Fiber

• Dietary fiber (DF) has been consumed for
  centuries and most food labels in the supermarket
  now list dietary fiber.
• Even though fiber is not considered a nutrient,
  health professionals and nutritionists agree that
  fiber is required in sufficient amounts for the
  proper functioning of the gastrointestinal tract.

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Definition

• DF is the edible parts of plants or analogous
  carbohydrates that are resistant to digestion and
  absorption in the human small intestine with
  complete or partial fermentation in the large
  intestine.

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Why ?

• DF consumption has established the basis for
  associating high-fiber diets in epidemiological
  studies with reduced risk of most of the major
  dietary problems in the U.S.A. namely, obesity,
  coronary disease, diabetes, gastrointestinal
  disorders, including constipation, inflammatory
  bowel diseases.

Chronic diseases
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Classification Of Dietary Fiber

• dietary fiber has been to differentiate dietary
  components on their solubility in a buffer at a
  defined pH, and/or their fermentability in an in
  vitro system using an aqueous enzyme solution
  representative of human alimentary enzymes.

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Solubility

• Soluble fiber dissolves in water
• This includes gums, mucilages, pectin and some
  hemicelluloses.
• found in all types of peas and beans like
  lentils, split peas, pinto beans, black beans,
  kidney beans, garbanzo beans, and lima beans, as
  well as oats, barley, and some fruits and
  vegetables like apples, oranges, and carrots.

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Benefits

• For people with diabetes, eating foods that
  contain soluble fiber can help control or lower
  the level of sugar in their blood and decrease
  insulin needs
• It may also help lower blood cholesterol levels,
  especially LDL-cholesterol or the bad
  cholesterol.

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• Insoluble fiber does not dissolve in water.
• Whole grains, wheat and corn fiber, and many
  vegetables like cauliflower, green beans, and
  whole potatoes are good sources of insoluble
  fiber.
• aids digestion by trapping water in the colon.
• helps prevent two kinds of intestinal diseases,
  diverticulosis and hemorrhoids.

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Fermentability

• Fibers that are well fermented include pectin,
  guar gum, acacia (gum arabic), inulin,
  polydextrose, and oligosaccharides.
• Generally, well fermented fibers are soluble in
  water, while partially or poorly fermented fibers
  are insoluble.

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Physiological Effects of D fiber

• major physiological effects of dietary fiber
  originate from the interactions with colonic
  content throughout its fermentation.
• It influences several metabolic processes,
  including the absorption of nutrients,
  carbohydrate and fat metabolism, and cholesterol
  metabolism.

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• influences the colonic structure and barrier
  function, and as the large intestine encompasses
  a significant body of the human immune system.
• Some form gels (pectins), while others have a
  high water holding capacity (WHC).
• its ability to adsorb or bind bile acids and its
  fermentability by microorganisms in the gut.

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Colonic Fermentation And Its Consequences

• The large intestine is the most heavily colonized
  region of the digestive tract, with up to 1011
  -1012 anaerobic bacteria /gram.
• end products produced from the fermentation,
  including gases (methane, hydrogen, carbon
  dioxide), short chain fatty acids (SCFA).
• Increases in microbial mass from fiber
  fermentation contribute directly to stool bulk

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• Gas production from colonic fermentation can also
  have some influence on stool bulk.
• Poorly fermented cellulose produces very little
  acid during its fermentation, most of which is
  only acetic acid by contrast, in the case of
  more fermentable fibers, large quantities of SCFA
  are formed.
• The metabolic end products of fermentation
  including the gases, SCFA, and increased
  microbiota, play a pivotal role in the
  physiological effects of fiber and implications
  for local effects in the colon and systemic
  effects

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PHYSIOLOGICAL FUNCTIONS OF DIETARY FIBER

• Dietary Fiber And Cancer
• Colon cancer is one of the leading causes of
  cancer morbidity and mortality among both men and
  women in the Western countries, including the
  U.S.A.
• Dietary Fiber And Carbohydrate Metabolism
• An association between insufficient dietary fiber
  intake and increased risk of diabetes has been
  postulated since 1970s.

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• Dietary Fiber, Lipid Metabolism, And
  Cardiovascular Disease
• bind bile acids increasing their excretion and
  decrease cholesterol in the liver.
• SCFA are absorbed from the colon to the liver.
• Dietary Fiber, Mineral Bioavailability And Bone
  Health.
• certain highly fermentable fibers have resulted
  in improved metabolic absorption of certain
  minerals, such as calcium, magnesium, and iron,

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• Dietary Fiber, Role In Gut Barrier Function And
  Gastrointestinal Disorders.
• SCFA stimulating repair in a damaged colon.
• barrier to prevent foreign materials from dietary
  or microbial origin from crossing into the
  internal body cavity. Prevent Intestinal
  permeability or leaky gut syndrome.

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Probiotics

• Intestinal tract is home to one hundred trillion
  (1014) microorganisms.
• called the intestinal microflora.
• over 400 different species of microbes.
• The 400 species of microbes living in your body
  are fighting for space. They want to live, thrive
  and reproduce in your intestinal tract, an
  environment that offers the ideal temperature,
  humidity and food sources.

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• Depending on the type of bacteria, there is a
  different effect on the body bacteria can have
  healthy, e.g.,
• immune-boosting benefits or cause harm to the
  body.
• A careful balance is necessary for health.

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• Bad microbes live in your intestines and normally
  do not cause any disease-like symptoms.
• Bad microbes flourish in an alkaline environment.
• Opportunistic and neutral the majority.
• Good microbes found in the body, called
  probiotics.
• Probiotics have a positive impact on the bodys
  health. They prefer a more acidic intestinal
  environment. Many of the probiotics are called
  lactic acid bacteria.

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They define the term probiotic as live
microorganisms which when administered in
adequate amounts confer a health benefit on the
host.
How do they work? What are these health
benefits? How can we get them? What species can
provide them? Whats the relationship with
Chronic diseases? How can we maintain them?
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Some history

• Pasture 1880,
• Eli Metchnikoff 1908,
• Tisser 1900,
• W W I Nissil
• Southeast Asia, Boulardi. Cholera.
• 1950, group of scientists, found out that mice
  that were given oral antibiotics, which kill all
  bacteria, including probiotics, were more
  susceptible to infection.

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• Yakult Company of Japan in the 1930s. Yakult
  Company introduced a fermented milk product that
  contained a probiotic culture.
• The term probiotic was not actually coined until
  the 1960s.
• In 1978, Dr. Tomotari Mitsuoka, illustrated how
  the composition of intestinal flora changes
  during a lifetime.
• Probiotics decrease with aging.
• WHY?

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How Do Probiotics Work?

• The intestinal microflora has the metabolic
  activity potential equal to that of the liver,
  the most active organ in the body!
• The exact mechanisms of action by which
  probiotics elicit their beneficial effects are
  not fully understood.

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Suggested mechanisms

• Probiotics Compete for Receptor Sites

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• Change secretion to mask receptors

mucus
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• Probiotics Affect the Immune System
• Gastrointestinal tract is equipped with effective
  immune system, the most number of lymphoid is
  around the gut.
• Immune system is the key element of what to enter
  your body or not to.
• By producing antibodies these are messengers for
  all tissues connected with immune system.
• Probiotics supplementation is useful in a wide
  variety of immune-based ailments including
  allergies, asthma, eczema and irritable bowel
  disease.

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• probiotics help balance good and bad messengers
  of the immune system by keeping the system in
  check.
• The result is healthy immune reactions and a
  healthier you. A careful balance of inflammation
  is required in the intestinal tract.
• Too much of an immune reaction can result in
  inflammation and damage to the intestines
  reducing their ability to digest and absorb
  nutrients I B D.

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• Too little immune reaction allows pathogens to
  grow in the intestines, causing infectious
  diarrhea, which can develop into a chronic
  illness such as allergies.
• All in all, it appears that probiotics
• reduce allergic reactions
• improve overall immunity
• promote proper immune reactions against pathogens.

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• Probiotics Consume Available Nutrients
• There are lots of nutrients available in the
  digestive tract that support the needs of lactic
  acid bacteria to grow. By consuming a large
  portion of the available nutrients suitable for
  microbes, lactic acid bacteria restrains the
  growth of bad microbes.
• Probiotics Create an Acidic Environment
• Many bad microbes do not like a low pH.

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• Probiotics Produce Beneficial Enzymes
• The enzyme activity of probiotics has been found
  to help fight infectious disease, lactose
  intolerance, immune system deficiencies, and
  urogenital and vaginal diseases.
• Probiotics Produce Antimicrobial Effects
• Many of the probiotic strains of bacteria are
  able to produce substances that kill bacteria,
  called bacteriocins

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• Probiotics Support Gut Barrier
• Lactobacilli and Bifidobacteria produce fats that
  encourage the growth of cells that line the
  intestinal tract. These fats are called short
  chain fatty acids. These fats also have
  nutritional effects on the intestinal cells,
  keeping them well nourished and healthy.
• Gut integrity.

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• Probiotics Encourage Healthy Microflora
• In clinical trials, the use of combinations of
  probiotic species has been found to offer greater
  health benefits than any one of the probiotic
  species alone.
• Example
• Lactobacillus reuteri produces protein to enhance
  the growth of other lactobacilli.