2. Definition
• The Functional Food Center (FFC),Texas defines
“functional food” as natural or processed foods that contains
known or unknown biologically-active compounds; which, in
defined, effective non-toxic amounts, provide a clinically
proven and documented health benefit for the prevention,
management, or treatment of chronic disease.
This definition is unique because of its acknowledgement of
“bioactive compounds”; or biochemical molecules that
improve health through physiological mechanisms.
Also, this definition notes that bioactive compounds must be
taken in non-toxic amounts, because bioactive compounds
have upper limits before they become dangerous.
3. Functional foods are those that when consumed regularly exert a specific health-beneficial effect beyond their
nutritional properties (i.e., a healthier status or a lower risk of disease), and this effect must be scientifically
proven (ILSI, 2008).
Health Canada defines functional food as a product that resembles a traditional food but
possess demonstrated physiological benefits (Shahidi, 2009).
In South Korea, functional foods are defined as dietary supplements whose function is to
supplement normal diet, and have to be marketed in measured doses, such as pills, tablets, etc.
(Kim et al., 2007).
Functional food should be a food similar in appearance to a conventional food (beverage, food
matrix), consumed as part of a usual diet, contains biologically active components with
demonstrated physiological benefits, and offers the potential of reducing the risk of chronic diseases
beyond basic nutritional functions (Food and Agricultural Organization of the United Nations (FAO), 2007).
4. • Change in the understanding of the role of foods
in human health promotion
• Consumer interest in active food
– Well being
– Life prolongation
– Prevention of initiation, promotion and
development of cancer
– Cardiovascular diseases
– Osteoporosis
Why Functional Foods?
Quinoa
5. CATEGORIES OF FUNCTIONAL
FOODS
Category Definition Examples
Basic Foods
Food or a food product that
naturally contains bioactive
compound
Carrots naturally contain beta-
carotene
Oat bran cereals naturally
contain beta-glucan
Processed Foods with added
bioactives
Bioactive is added to the food
during processing Orange juice with added calcium
Milk with added omega-3 fatty
acids
Foods enhanced to have more
of a bioactive
The bioactive exists naturally in
the food but the level of
bioactive is modified or
concentrated (e.g., by genetic
engineering or breeding)
Yoghurt with increased levels of
prebiotic
Tomatoes with increased
lycopene content
Eggs with increased levels of
omega-3 fatty acids
6.
7. FUNCTIONAL FOODS FROM PLANT
SOURCES
The most important phytochemicals are phenolics and carotenoids
in fruits and vegetables, and lignans, b-glucan, and inulin in cereal-
based products.
Preventing cancer and CVDs, reducing tumor incidence, lowering of
blood pressure, risk of heart disease, cholesterol, and delaying
gastric emptying are some of the important protective effects of
plant-based foods.
8. RICE
Rice bran contains high level of dietary fibers (b-glucan, pectin, and
gum), tocotrienols, g-oryzanol, and b-sitosterol, which help in
lowering of the plasma level of various parameters of lipid profile
(Chaturvedi et al., 2007).
Rice bran contains a-lipoic acid, which assists in metabolizing
carbohydrates and fats, thus lowering glycemic index and controlling
the body weight.
Rice bran is potentially a valuable source of natural antioxidants
such as tocopherols, tocotrienols, and oryzanol (Godber and Wells,
1994).
Antioxidants from rice bran can potentially satisfy the demand of
finding effective and economical natural antioxidants, and is one of
the interesting areas of research
9. OATS
Oat products are the widely studied dietary source of the
cholesterol-lowering soluble fiber known as b-glucan.
Apart from this, various studies focus on some specific oat extracts
such as tocols (Vitamin E) and aventhramides.
There is now significant scientific agreement that consumption of
this particular plant food can reduce total and LDL cholesterol,
thereby reducing the risk of coronary heart disease (CHD) (Truswell,
2002).
As a grain without gluten, oat flour and bran are used as an
alternative food for persons suffering from celiac diseases (Butt et al.,
2008), as it helps in delaying gastric emptying, diminishes absorption
of nutrients, affects the motility in the small bowel, and prolongs
satiety after the meal (Malkki and Virtanen, 2001).
10. SOY
Soybeans are unique source of isoflavones (genistein and diadzein)
which have numerous biological functions. It is thought to play
preventive and therapeutic roles in CVD, cancer, osteoporosis, and
the alleviation of menopausal symptoms (Potter, 1995).
Regarding the specific component responsible for the cholesterol-
lowering effect of soy, recent attention has focused on isoflavones
(Potter, 1998).
11. FLAXSEED
Flax (Linum usitatissimum) is an important oil seed crop, and among
the major seed oils, flaxseed oil contains mainly (57%) the omega-3
fatty acid, i.e., a-linolenic acid. It contains a variety of essential and
protective nutritive compounds, some of which are rarely available
from other foods (Oomah, 2001).
Since flaxseed is a leading source of omega-3 fatty acid, a–linolenic
acid, and phenolic compound lignan, it is for these compounds that
incorporation of flaxseed in diet has been attractive for the
development of functional foods with specific health benefits.
The two primary mammalian lignans, enterodiol and its oxidation
product, enterolactone, are formed in the intestinal tract by bacterial
action on plant lignan precursors (Setchell et al., 1981).
12. GARLIC
Potential health benefits of Allium vegetables, in particular, garlic
(Allium sativum) has its origin in antiquity.
Healthful properties of garlic are numerous, including cancer
chemopreventive, antihypertensive, and cholesterol-lowering
properties, free radical scavenging activities, immune stimulation,
curing CVDs, and anti-infectious properties (Srivastava et al., 1995;
Borek, 2006; Singh et al., 2007)
The characteristic flavor and pungency of garlic are due to an
abundance of oil- and water-soluble, sulfur-containing elements,
which are probably responsible for the various medicinal effects
ascribed to this plant.
13. The intact garlic bulb contains an odorless amino acid, alliin, which
is enzymatically converted by allinase into allicin when the garlic
cloves are crushed (Block, 1992).
This latter compound is responsible for the characteristic odor of
fresh garlic.
Allicin then spontaneously decomposes to form numerous sulfur-
containing compounds, some of which have been investigated for
their chemopreventive activity (Butt et al., 2009)
14. TEA
The important constituents of green tea are polyphenols, particularly
flavonoids. Polyphenols comprise up to 30% of the total dry weight of
fresh tea leaves.
Catechins are the predominant and the most significant of all tea
polyphenols (Graham, 1992).
The four major green tea catechins are epigallocatechin-3-gallate,
epigallocatechin, epicatechin-3-gallate, and epicatechin (Hayat et al.,
2013).
the anti-inflammatory effects of black tea are responsible for
guarding against CVD development (Steptoe et al., 2007).
15. FUNCTIONAL FOODS FROM ANIMAL
SOURCES
Dairy Products:
Milk is one of the best sources of calcium, an essential nutrient which
can prevent osteoporosis and possibly colon cancer (Alvarez-Leon
et al., 2006)
In addition to calcium, however, recent research has specifically
focused on other components of dairy products, particularly
fermented dairy products, known as probiotics.
These have been historically used to rebalance disturbed intestinal
microflora and to diminish gastrointestinal disorders, such as diarrhea
or bowel disorders.
16. Fish:
Omega-3 (n-3) fatty acids are an essential class of polyunsaturated
fatty acids (PUFAs) derived primarily from fish oil.
Possible association between eating fish and inflammation-related
diseases, such as rheumatoid arthritis, has been observed since the
omega 3- fatty acids present in fish oil is believed to have anti-
inflammatory effects (Simopoulos, 1991).
The cardioprotective effect of fish consumption has been observed
in some prospective investigations (Krumhout et al., 1985) but not in
others (Ascherio et al., 1995)
17. NUTRACEUTICALS
Nutraceuticals are biologically active molecules found in foods that may not
be essential for maintaining normal human functions, but may enhance
human health and wellbeing by inhibiting certain diseases or improving
human performance.
Numerous classes of nutraceuticals are found in both natural and
processed foods, including carotenoids, flavonoids,
curcuminoids, phytosterols, and certain fatty acids.
##“Pharmaceuticals” may be considered as drugs used mainly to treat
diseases, while “nutraceuticals” are those that are intended to prevent
disease.
18. The term “nutraceutical” was coined from “nutrition” and “pharmaceutical”
by Stephen De Felice, founder and chairman of the Foundation for Innovation
in Medicine, Cranford, NJ, in 1989.
According to De Felice, nutraceutical can be defined as “a food (or a part of
food) that provides medical or health benefits, including the prevention and
or treatment of a disease” (Das et al., 2012).
Nutraceuticals may range from isolated nutrients, herbal products, dietary
supplements, and diets to genetically engineered designer foods and
processed products such as cereals, soups, and beverages (Dureja et al.,
2003; Malik, 2008)
19. CLASSIFICATION
Nutraceuticals can be classified on the basis of either their chemical
nature, the type of food items or whether they are traditional or not.
1. On the basis of the chemical constituents: phenols, alkaloids,
fibers, fatty acid, minerals, terpenes, etc.
2. Traditional/nontraditional: fruits, vegetables, fortified juices.
3. Type of food items: vitamins, minerals, dairy products.
20. Broadly, nutraceuticals can be classified into two groups (Pandey et al.,
2010):
1. Potential nutraceuticals
2. Established nutraceuticals
A potential nutraceutical could become an established one only after
efficient clinical data of its health and medical benefits are obtained. It is
to be noted that much of the nutraceutical products still lay in the
potential category
21. On the basis of food sources, nutraceutical substances can be grouped as plants,
animals, and microbial sources.
• In case of classification by mechanism of action, nutraceuticals can be grouped as
those having antioxidant, antibacterial, antihypertensive, anti-inflammatory,
anticarcinogenic, anti-aggregate, influence on blood or lipid profile, osteoprotective,
and so on. This classification is based on the proven or purported physiological
properties of the nutraceutical substances.
• On the basis of chemical nature, nutraceuticals can be grouped as the following:
Carbohydrates and their derivatives
Fatty acids and lipid structures
Microorganisms
Proteins and amino acid structures
Phenolic compounds
Isoprenoid derivatives
Minerals
22.
23. MODE OF ACTION
It has been stated that they function by increasing the supply of
important building blocks to the body.
The supply of these essential building blocks can be done by two
ways:
(1) by reducing signs of the disease as buffering agents for relief.
and (2) by directly providing benefits for health of the individuals.
25. BENEFITS
Immunity boosters (flavonoids, green tea, quercetin in onion).
Aid in recovering from degenerative diseases (vitamin E, creatine,
turmerine).
They have benefits against obesity- soy foods, flavonoids, green tea
extracts.
Some of them such as green tea, dietary fibers, antioxidants have
proven to be antidiabetic also.
Some are anticancer agents such as lycopene, soy foods, saponins
from spinach, tomato, and potato.
26. DIETARY FIBRE
Dietary fiber is defined as the plant part that is not hydrolyzed by enzymes
secreted by the human digestive tract, but digested by microflora in the gut.
Dietary fibers mostly include non-starch polysaccharides such as celluloses,
hemicelluloses, gums, and pectins as well as oligosaccharides like lignin, resistant
dextrins, and resistant starches.
Dietary fibers are divided into two forms:
(1) insoluble dietary fiber, which includes celluloses, some hemicelluloses, and
lignins having bulking action and are fermented to a limited extend in the colon.
(2) Soluble dietary fiber, which includes β-glucans, pectins, gums, mucilages, and
hemicelluloses that are viscous and fermented in the colon
27. A good intake of dietary fiber lowers the risk of several diseases like
coronary heart disease (Liu et al., 1999),
stroke (Steffen et al., 2003),
hypertension (Whelton et al., 2005),
diabetes (Montonen et al., 2003),
obesity (Lairon et al., 2005), and certain gastrointestinal disorders (Petruzziello et al., 2006).
Again, increase in the intake of high fiber food improves serum lipoprotein values (Brown et
al., 1999),
lowers blood pressure level (Keenan et al., 2002),
improves blood glucose control for diabetes (Anderson et al., 2004),
aids weight loss (Birketvedt et al., 2005),
and promotes regularity (Cummings, 2001).
28. PROBIOTICS AND PREBIOTICS
A probiotic can be defined as live microorganism, which when administered
in adequate amounts has beneficial effect on the host animal.
Species of lactobacillus and bifidobacterium are most commonly used in
the manufacture of probiotic products for their known effects on human
health as well as their “generally recognized as safe” status (O’Bryan et al.,
2013).
Apart from these, yeast, Escherichia coli, and some bacilli can also be
considered as probiotics.
31. Administration of probiotics reduces the symptoms of antibiotic-associated
diarrhea or due to rotavirus (Gill and Guarner, 2004).
Specific strains of lactic acid bacteria, when consumed in certain numbers, can
modulate aspects of both natural and acquired immune responses.
Probiotic therapy can lower the risk of colon cancer by reducing the
concentration of the cancer-promoting enzymes and putrefactive metabolites in
the gut (de Vrese and Schrezenmeir, 2008).
32. Prebiotics are dietary ingredients that beneficially affect the host by
selectively altering the composition or metabolism of the gut microbiota.
These are short-chain polysaccharides that have unique chemical
structures that are not digested by humans; in particular, fructose-based
oligosaccharides that exist naturally in food and are also added in food.
Vegetables like chicory roots, banana, tomato, and alliums are rich in
fructo-oligosaccharides.
Some other examples of these oligosaccharides are raffinose and
stachyose, found in beans and peas.
The health benefits of the prebiotics are mostly indirect.
They generally promote the lactobacillus and bifidobacterial growth in
the gut, thus helping in metabolism (Gibson, 1999; Hord, 2008).
33. OMEGA FATTY ACIDS
Polysaturated fatty acids or PUFAs have two main subdivisions: omega-3 (n-3)
fatty acids and omega-6 (n-6) fatty acids based on the location of the last double
bond.
Omega-3 fatty acids mostly consist of α-linolenic acid (ALA), eicosapentaenoic
acid (EPA), docosahexaenoic acid (DHA).
ALA is the precursor of EPA and DHA.
Omega-6 fatty acids mainly consist of linoleic acid (LA), γ-linolenic acid (GLA),
and arachidonic acid (ARA),
LA being the parent fatty acid of this group.
EPA and DHA are found mainly in fatty fishes such as mackerel, salmon, herring,
trout, bluefin tuna, and fish oils (Ackman, 2008).
34. Sources of ALA:
flaxseed,
soybeans,
canola,
some nuts (e.g. walnuts),
red/black currant seeds
LA occurs mainly in:
vegetable oils, for example corn, safflower, soybean, and sunflower
ARA:
in animal products such as meat, poultry, and eggs as well as algae and other
aquatic plants
35.
36. biological functions ranging from blood pressure and blood clotting to the
development and functioning of the brain and nervous system, important roles
in immune regulation and inflammation (Calder, 2009; Wall et al., 2010).
By increasing the ratio of (n-3):(n-6) fatty acids in the diet, reductions may be
achieved in the incidence of chronic inflammatory diseases.
37. ANTIOXIDANT VITAMINS
oThe principal micronutrient antioxidants of the body like vitamin E (α-
tocopherol), vitamin C (ascorbic acid), and β-carotene can scavenge free
radicals.
oThese vitamins are present in nature in a number of fruits and vegetables.
oVitamins act singly or synergistically in the prevention of a number of
oxidative reactions leading to degenerative diseases like cancer,
cardiovascular diseases, and cataracts (Elliot, 1999).
oVitamin E, which comprises of tocopherols together with tocotrienols,
functions as an in vivo antioxidant, protecting tissue lipids from free radical
attack (Meydani, 2000).
oα-Tocopherol acts either by donating a hydrogen radical to remove the free
lipid radical, reacting with it to form nonradical products, or simply by
trapping the lipid radical.
38. Vitamin E and selenium have a synergistic role against lipid peroxidation.
Vitamin C is considered as the most important antioxidant in extracellular
fluids (Sies and Stahl, 1995).
It is a reducing agent and can reduce and thereby neutralize reactive oxygen
species (Padayatty et al., 2003). It also acts by interacting with other
antioxidants.
Glutathione is important in recycling oxidized vitamin C, and vitamin C itself
is crucial to the regeneration of lipid-bound vitamin E (AHRQ, 2003).
Carotenoids like lycopene, β-carotene, lutein, and zeaxanthin are known to
be the most efficient singlet oxygen quencher in the biological systems.
39. POLYPHENOLS
Some of the most common classes of polyphenols in food are flavonoids,
phenolic acids, stilbenes, and lignans. Polyphenolic compounds in diet affect
human health by their antioxidant, antimicrobial, anti-inflammatory, vasodilating,
and prebiotic properties (Landete, 2012).
The mechanism followed by the polyphenols on human diseases is via numerous
cellular processes like
gene expression,
apoptosis,
platelet aggregation,
intercellular signaling, and related machinery.
40.
41.
42. Mechanisms by which polyphenols may have an influence on cardiovascular
diseases are antioxidant, antiplatelet, and anti-inflammatory properties,
inhibiting LDL oxidation, increasing HDL, and improving endothelial function
Quercetin, cocoa flavonoids, tea catechins, red wine, and purple grape juice
have shown to contribute in reducing cardiovascular diseases
In controlling diabetes, the mechanism followed here is like inhibition of
glucose absorption by the gut or by peripheral tissues (Pandey and Rizvi,
2009).
Polyphenols such as catechins, epicatechins, epigallocatechins from tea,
isoflavones from soybean, tannic acid, glycyrrhizin from licorice root,
chlorogenic acid, and saponins decrease the intestinal transport of glucose
(Pandey and Rizvi, 2009).
43. Anthocyanin from grape fruits, resveratrol from grapes, and catechin from
green tea and other fruit and vegetables having high levels of flavonoids have
reported to exert preventive effects against aging
Flavonoids act against the neurodegenerative disease by ways of protecting
vulnerable neurons, enhancing existing neuronal functions, and by stimulating
neuronal regeneration
Epidemiological studies revealed association of apple and soy isoflavone
genistein intake with better lung function in asthmatic patients (Woods et al.,
2003; Smith et al., 2004).
44. HERBS AND SPICES
possess antioxidative, chemopreventive, antimutagenic, anti-inflammatory,
or immune-stimulating properties, which help in reducing human diseases like
cancer, cardiovascular diseases, diabetes, gastrointestinal diseases, and other
metabolic diseases
Chemoprevention helps in the prevention of cancer by different spice-derived
nutraceuticals. In this regard, the potential of turmeric (curcumin), red chili
(capsaicin), cloves (eugenol), ginger (zerumbone), fennel (anethole), kokum
(gambogic acid), fenugreek (diosgenin), black cumin (thymoquinone), and ursolic
acid from rosemary has been established.
Some of the spices or their bioactive compounds extensively studied for their
antidiabetic properties are fenugreek, turmeric, garlic, onion, and cumin
(Srinivasan, 2005). One of the active components identified in fenugreek for its
antidiabetic and antidyslipidemic effects on animal models is the amino acid 4-
45. Hypoglycemic potency of garlic and onion has been attributed to their
sulfur compounds
Studies revealed that in human red blood cell membranes, lipid
peroxidation is inhibited by curcumin from turmeric, capsaicin from chili,
and eugenol from clove
In vitro studies suggest that the extracts from dietary spices and
medicinal herbs possess antibacterial activities against several food-borne
pathogens like Bacillus cereus, Listeria monocytogenes, Staphylococcus
aureus
E. coli, Salmonella anatum, Aspergillus, Candida, and other species
46. MINERALS
Minerals are inorganic substances essential for the human body to carry out
certain physiological functions
Minerals are broadly divided into two groups, that is the major minerals or
the macro minerals and the trace minerals or the micro minerals. Macro
minerals are major as their daily requirement to an individual is 100 mg or
more, whereas micro minerals have their daily requirement of less than 20
mg for an individual
macro minerals are calcium, sodium, chlorine, phosphorus, magnesium,
potassium, and sulfur,
micro minerals are zinc, copper, iron, magnesium, chromium, cobalt,
selenium, iodine, and molybdenum
47. In addition to their role in maintaining the body electrolyte balance
(sodium, chloride, potassium), minerals have others functions like:-
blood in the body (iron, copper),
building healthy bones (calcium, phosphorus, magnesium, fluoride),
maintaining a healthy immune system (zinc),
and finally oxidizing the excess free radicals produced in the body
(selenium).