2. Learning Objectives
At the end of this lesson, the student will know:
• What are phytonutrients?
• What their functions are in the human body
• The way they act
• Some important phytonutrients
3. What are they?
• Phytonutrients (also referred to as
phytochemicals) are compounds found in plants.
• They serve various functions in plants, helping to
protect the plant's vitality.
• For example, some phytonutrients protect the
plant from UV radiation while others protect it
from insect attack.
4. • Not only do phytonutrients award benefit to the
plants but they also provide benefits to those who
enjoy plant food.
• That's because they have health-promoting
properties including antioxidant, anti-inflammatory,
and liver-health-promoting
activities.
5. • Phytonutrients aren't essential for keeping us
alive, unlike the vitamins and minerals that plant
foods contain.
• But when we eat or drink phytonutrients, they
may help prevent disease and keep our body
working properly.
6. Why are colors important?
• Interestingly, a lot of the phytochemicals that are
good for us also produce bright colors in
vegetables and fruits.
• This is where the saying "Eat Your Colors" comes
from.
• It's also important to understand that each of these
foods contains many different phytochemicals that
can take care of different oxidation reactions in our
cells.
7. Health benefits of Phyto-nutrients
Studies have found that
certain chemicals other
than nutritional principles in
them have anti-mutagenic,
free radical scavenging and
immunity boosting
functions, which help
promote health and prevent
diseases, apart from their
nutritive value.
8. Mode of Action
• Studies suggest that cancers occur due to a
series of mutational events occurring at the
cellular level triggered by free-oxygen radicals
and reactive oxygen species (ROS).
• These free radicals have the ability to damage
cell’s DNA, cell membrane and proteins like ion
channels, receptors, etc.
9. • Antioxidants by virtue of their reduction potentials
can bind to oxidation radicals at these levels
interrupt free-radical injury by reversing or limiting
the extent of damage.
• Several groups of antioxidants have been
identified such as poly-phenolic flavonoids,
anthocyanins, etc.
10. Types
• Non-digestible carbohydrates, natural acids
and enzymes
• Some phytochemicals include detoxifying agents
like non- starch polysaccharides (NSP) or dietary-fiber
like gums, hemicellulose, mucilage, pectin,
tannins, and alkaloids like caffeine and non-protein
amino acids.
11. • NSP or dietary fiber increase bulk to the food and
helps prevent constipation by decreasing gastro-intestinal
transit time.
• They also bind toxins in the food, prevent their
absorption, and help protect the colon mucus
membrane from diverticulitis and cancers.
• In addition, dietary fibers bind to bile salts
(produced from cholesterol) and decrease their
re-absorption, thus help lower serum LDL
cholesterol levels.
12. Plant Vitamins and Minerals
• Pro-vitamin A (beta carotene)
• Vitamin C
• Vitamin K
• Vitamin E
• Most B vitamins (except B12)
• Many minerals
13. Plant sterols
• Plant sterols also known as phyto-sterols
constitute mainly beta-sitosterol, however, differ
in function than human sterols like cholesterol.
• They are poorly absorbed by humans and in the
process, appear to block the absorption of dietary
cholesterol as well; and thus help reduce blood
LDL cholesterol levels.
14. • Initial research studies have been found that
experimental doses of plant sterols can be
effective in countering the effects of testosterone-mediated
hypertrophy in prostate glands.
• Again, they help minimize the risk of BPH and
prostate cancer in men.
• Their effects in women, however, are found to be
neutral or some beneficial effect on breast,
uterine and ovarian receptors.
17. Terpenoids
• Terpenoids, also referred to as isoprenoids, are
naturally occurring chemicals found in all types of
living things.
• Plant terpenoids are known for their aromatic
qualities – contributing to the scent of eucalyptus
and the pungent flavours of cinnamon, cloves,
mint and ginger.
18. Tri-terpenoids
• Saponins – soybeans, beans, other legumes,
maize, alfalfa.
• Oleanolic acid - American pokeweed, garlic, java
apple, cloves.
• Ursolic acid - apples, basil, bilberries,
cranberries, elder flower, peppermint, lavender,
oregano, thyme, prunes.
• Betulinic acid - Ber tree, white birch, persimmon
family, jambul (Syzygium formosanum), chaga,
and many other Syzygium species.
20. Carotenoids
• Carotenoids are the natural fat-soluble pigments
that provide the colors of many red, green, yellow
and orange fruits and vegetables.
• They act as powerful antioxidants and are used to
make vitamin A.
• Some well-known carotenoids are alpha- and
beta-carotene, lutein, lycopene, zeaxanthin.
21. • Carotenoids have been shown to reduce the risk
of certain types of cancer – specifically,
1. premenopausal breast cancer
2. cervical,
3. prostate,
4. digestive tract and
5. lung cancers.
• However, excessive consumption by smokers
has been linked to an increased risk of lung
cancer.
25. Other health benefits attributed to carotenoids
include protection against:
• heart disease,
• cataracts and macular degeneration,
• improvement in blood sugar regulation, and
• protection of nerve cells, which may help prevent
or reduce the severity of Alzheimer’s disease.
27. • Ellagic Acid: Ellagic acid is found in a number of
berries and other plant foods, especially:
Strawberries, Raspberries and Pomegranates
• Ellagic acid may help protect against cancer
through several different ways.
• It may cause apoptosis of cancer cells.
• And it may help the liver neutralize cancer-causing
chemicals in our blood.
28. • Tannic Acid:
• Tannic acid can be applied directly to affected
areas to treat cold sores and fever blisters, diaper
rash and prickly heat, ingrown toenails,
• Mouth wash and gargles for sore throat, sore
tonsils, spongy or receding gums, and skin-rashes;
and to stop bleeding.
• Tannic acid is also taken by mouth for chronic
diarrhea, dysentery, bloody urine, painful joints,
persistent coughs, and cancer.
29. Phenols
• Phenols are organic chemicals characterized by the
presence of phenol structural units.
Biological role in plants:
1. Release and suppression of growth hormones.
2. UV screens to protect against ionizing radiation
and to provide coloration (plant pigments).
3. Deterrence of herbivores.
4. Prevention of microbial infections (phyto-alexins).
5. Signaling molecules in ripening and other growth
processes.
30. Phenolic
acids
Isoflavones
(soy)
Flavones
(red-pepper)
Polyphenols
Flavanoids Stilbenes
Flavonones
(citrus fruits)
Flavonols
(colorless)
Anthocyanins
(blue and
purple)
Flavan-3-ols
(tea, red wine,
cocoa)
Proanthocyanidines
(dark fruits)
Polyphenols are powerful antioxidants in the body.
31. • Bioflavonoids have been termed “natural
biological response modifiers” because of their
ability to adapt and moderate the body’s reaction
to microbes – allergens, viruses, and carcinogens.
• They have the demonstrated antiallergenic, anti-inflammatory,
antimicrobial, and anti-cancer
activity.
• Bioflavonoids also serve as powerful antioxidants,
protecting against oxidative stress and free-radical
damage.
33. Curcuminoids
• The curcuminoids are natural phenols that are
responsible for the yellow color of turmeric.
• Research has identified curcumin as the agent
responsible for most of the biological activity of
turmeric.
• Curcumin has shown antioxidant, anti-inflammatory
and anticancer effects.
• It may reduce iron absorption.
34. • Diagnostic use
• Preliminary research has found that curcuminoid
binds to amyloid proteins associated with
Alzheimer's disease.
• Because curcumin increases fluorescent activity
after it binds to amyloid protein, curcumin is being
studied as a possible identifier.
• Tests have detected amyloid proteins in human
eyes, offering the possibility that simple eye
exams could provide early detection of the
disease.
35.
36. Polyphenols/Bioflavanoids
• These are red, blue, purple pigments.
• They may affect cell-to-cell signaling, receptor
sensitivity, inflammatory enzyme activity and
gene regulation.
• Polyphenol antioxidant’s ability is to scavenge
free radicals and up-regulate certain metal
chelation reactions.
Cocoa is the prime
ingredient of
chocolate, a source of
polyphenols.
37. Anthocyanins
• Present in red wine, many red, purple or
blue fruits and vegetables.
• Pelargonidin – bilberry, raspberry,
strawberry.
• Peonidin – bilberry, blueberry, cherry,
cranberry, peach.
• Cyanidin – red apple & pear, bilberry,
blackberry, blueberry, cherry, cranberry,
peach, plum, hawthorn, loganberry, cocoa.
• Delphinidin – bilberry, blueberry, eggplant.
38. Flavonols
• Flavonols such a quercetin has antioxidant
properties as well as anti-inflammatory effects.
• Quercetin – red and yellow onions, tea, wine,
apples, cranberries, buckwheat, beans.
• Gingerol – ginger.
• Kaempferol – tea, strawberries, gooseberries,
cranberries, grapefruit, apples, peas, brassicates
(broccoli, kale, cabbage), chives, spinach, leek,
tomatoes.
40. • Quercetin also inhibits the oxidation of low-density
lipoprotein (LDL is the “bad” cholesterol
that’s linked to an increased risk for heart
disease) and appears to offer protection against
cardiovascular disease.
• Preliminary research suggests that quercetin
exerts inhibitory effects on various types of
cancer, and it may also have antiviral action.
41.
42. • Quercetin’s best-known use is in the treatment of
seasonal allergies because of its antihistamine
effects.
• Quercetin has been found to improve the quality
of men suffering from chronic nonbacterial
prostatitis – inflammation of the prostate gland that
is often painful.
43. • Isoflavones are a subclass of bioflavonoids that
includes phytoestrogens such as lignans, which
may help to prevent the development of some
types of breast cancer.
44. • Isoflavones (phytoestrogens) are:
• Daidzein (formononetin) – soy, alfalfa sprouts,
red clover, chickpeas, peanuts, kudzu, other
legumes.
• Genistein (biochanin A) – soy, alfalfa sprouts, red
clover, chickpeas, peanuts, other legumes.
• Glycitein – soy.
• Pterocarpans or Coumestans
• Coumestrol – red clover, alfalfa sprouts, soy,
peas, brussels sprouts.
45. Phytoestrogens
• Soy foods contains an isoflavone that can behave
in the body like the hormone estrogen -
phytoestrogen.
• They can also block the effects of our natural
supply of estrogen.
• Some evidence suggests that soy foods may be
linked to:
• Lower risk of endometrial cancer
• Lower risk of bone loss in women
46.
47. Lignans
• Our body converts lignans, another type of
phytonutrient, into chemicals with some estrogen-like
effects.
• Two especially good sources of lignans are:
• Flaxseeds
• Sesame seeds
• However, research supporting a role for lignans in
preventing endometrial cancer or osteoporosis is
limited.
48. Flavan-3-ols (flavanols)
• Catechins – white tea, green tea, black tea,
grapes, wine, apple juice, cocoa, lentils, black-eyed
peas.
• Types of Catechin: Gallocatechin, Epicatechin,
Epigallocatechin, Epigallocatechin gallate
(EGCG) in green tea, Epicatechin 3-gallate.
• Theaflavin – black tea;
• Thearubigins.
• Proanthocyanidins.
49. • Green tea is an especially good source of
catechins, powerful antioxidants.
• The drink may help prevent certain types of
cancer.
51. • Hesperidin
• Found in citrus
fruits, this
flavonoid works
as an antioxidant.
• It can reduce
inflammation in
the body.
• It may also help
reduce the risk of
cancer.
53. • Resveratrol: Resveratrol is found in:
1. Grapes
2. Purple grape juice
3. Red wine
• It acts as an antioxidant and anti-inflammatory.
• Some research suggests that resveratrol might
reduce the risk of heart disease and cancer.
• And it may help extend people's life span.
54. Glucosinolates/Iso-thiocyanates
• Sulfur containing Glucosinolates are found in
cruciferous vegetables, including:
1. Brussels sprouts
2. Cabbage
3. Kale
4. Broccoli
55. • The sulfur compounds give these vegetables
their sharp odor and flavor.
• The glucosinolates turn into other chemicals
during the cooking process and while we digest
these foods.
• Our bodies metabolize glucosinolates into
isothiocyanates.
• And exposing cancer cells to benzyl,
isothiocyanate kills them by reducing STAT-3
protein, which promotes the survival and rapid
reproduction of cancer cells.
56. • The isothiocyanates in foods like kale, bok choy,
collard greens, and watercress halt the growth of
breast cancer, inhibit the progression of lung
cancer, cut the risk of colon and prostate cancer.
• Isothicyanate phytonutrients also prevent toxins
from damaging our DNA.
61. Capsaicin
• Capsaicin is an active component of chilli
peppers.
• The highest concentration of capsaicin can be
found in the white pith of the inner wall, where the
seeds are attached.
• Capsaicin is used as an analgesic in topical
ointments, nasal sprays and dermal patches.
• It may be applied for the temporary relief of minor
aches and pains of muscles and joints associated
with arthritis, backache, strains and sprains.
62. • Capsaicin creams are used to treat psoriasis as
an effective way to reduce itching and
inflammation.
• It selectively binds to a protein known as TRPV1
that resides on the membranes of pain and heat-sensing
neurons.
• Capsaicin may be used to help regulate blood
sugar levels by affecting carbohydrate breakdown
after a meal. It also increases satiety and reduces
energy as well as fat intake.
63. Wise Food Choices
• Experts agree that the phytonutrients in plant
based foods may help prevent disease and
promote health.
• Aim to include a variety of plant based foods
such as vegetables and fruit, whole grains,
nuts, seeds and legumes in your meals and
snacks every day.
64. Homework
• Make a list of foods you ate today.
• Find out some of the phytochemicals these
foods contained.