Nutrients and Health Benefits of Vegetables

NUTRIENTS AND HEALTH BENEFITS OF VEGETABLES

Presented by

PELIN B. BELINO, PhD. ,RND

Professor 2

Benguet State University

TOPIC OUTLINE

I. Nutrient Content Vegetables

II. Health Benefits of Vegetables

111. Functional Properties of

Vegetables


Why is it important to eat vegetables?

Eating vegetables provides health benefits – people who eat more vegetables and fruits as part of an overall healthy diet are likely to have a reduced risk of some chronic diseases

Vegetables provide nutrients vital for health and maintenance of your body

https://www.choosemyplate.gov/sites/default/files/misc/dietaryguidelines/MyPlateMyWinsTips.pdf


Nutrients

Most vegetables are naturally low in fat and calories. None have cholesterol

Vegetables are important sources of many nutrients, including potassium, folate (folic acid), vitamin A, vitamin C, and dietary fiber


Diets rich in potassium may help to maintain healthy blood pressure

Vegetable sources of potassium include white beans, tomato products (paste, sauce, and juice), beet greens, soybeans, lima beans, spinach, lentils, and kidney beans, leafy green vegetables


Dietary fiber from vegetables, as part of an overall healthy diet, helps reduce blood cholesterol levels and may lower risk of heart disease

Fiber is important for proper bowel function. It helps reduce constipation and diverticulosis. Fiber-containing foods such as vegetables help provide a feeling of fullness with fewer calories


Folate (folic acid) helps the body form red blood cells. Women of childbearing age who may become pregnant should consume adequate folate from foods, and in addition 400 mcg of synthetic folic acid from fortified foods or supplements

This reduces the risk of neural tube defects, spina bifida, and anencephaly during fetal development


Vitamin A keeps eyes and skin healthy and helps to protect against infections

Vitamin C helps heal cuts and wounds and keeps teeth and gums healthy

Vitamin C aids in iron absorption

HEALTH BENEFITS OF VEGETABLES

Eating a diet rich in vegetables and fruits as part of an overall healthy diet may reduce risk for heart disease, including heart attack and stroke

Eating a diet rich in some vegetables and fruits as part of an overall healthy diet may protect against certain types of cancers

https://www.choosemyplate.gov/sites/default/files/misc/dietaryguidelines/MyPlateMyWinsTips.pdf


Diets rich in foods containing fiber, such as some vegetables and fruits, may reduce the risk of heart disease, obesity, and type 2 diabetes.

Eating vegetables and fruits rich in potassium as part of an overall healthy diet may lower blood pressure, and may also reduce the risk of developing kidney stones and help to decrease bone loss


Eating foods such as

vegetables that are

lower in calories per

cup instead of some

other higher-calorie

food may be useful in helping to lower calorie intake

FUNCTIONAL PROPERTIES OF VEGETABLES

Functional foods are foods that provide physiological benefits beyond that of simply meeting nutrient needs

Functional foods are unmodified whole foods that naturally contain substances that provide a physiological benefit beyond that provided by the nutrients they contain

Some foods are considered functional because they are good sources of phytochemicals

What are Phytochemicals?

Phytochemicals refer to the chemicals found in plants

Many of these have health-promoting properties and are associated with reductions in the risk of cancer and other degenerative diseases

Some act as antioxidants, some affect the activity of enzymes or hormones, others work by other mechanisms

What are Phytochemicals?

Many phytochemicals have an anti-carcinogenic (anti-cancer) action by:

1. Slowing cell proliferation (division) by interfering with cell cycle

2. Inducing apoptosis (cell suicide)

3. Inhibiting phase 1 enzymes (enzymes that convert harmless substances into carcinogens)

4. Inducing phase 2 enzymes (enzymes that can attach carcinogens to molecules that facilitate speedy excretion

FUNCTIONAL PROPERTIES I. FLOWER VEGETABLES

BROCCOLI (Brassica oleraceae L. var.italica)

Broccoli is rich in fiber, provitamin A carotenoids, and vitamins C and K

Functional Properties

Cruciferous vegetables contain phytochemicals which help create immune and antioxidant support in the body by inducing extra protection of the enzymes involved in detoxifying carcinogens and flushing them out of the body

Broccoli is an important source of Vitamin K, which helps prevent stomach and colon cancer


1. Carotenoids (ά-carotene, β-carotene, β-cryptoxanthin, lutein, zeaxanthin)

Carotenoids are phytochemicals that have antioxidant properties

The intake of carotenoid-containing fruits and vegetables has been associated with a reduced risk of certain cancers, cardiovascular disease, and age-related eye diseases such as cataracts and macular degeneration

The antioxidant properties of carotenoids are believed to be responsible for some of these effects


Beta-carotene is the best known carotenoid

The carotenoids lutein and zeaxanthin are most strongly associated with reduced risk of macular degeneration - the leading cause of severe vision loss in people over age 60. It occurs when the small central portion of the retina, known as the macula, deteriorates


2. Glucosinolates (Glucobrassicin)

The consumption of cruciferous vegetables has been associated with a reduced risk of cancer of the lung, stomach, colon and rectum and also reduced risk of coronary heart disease

These effects have been attributed to their high concentration of glucosinolates


Glucosinolates convert to isothiocyanates (contain sulfur) when vegetables containing them are cut

Isothiocyanates can reduce poisonous effects of carcinogens and act by inhibition of cell proliferation and induction of apoptosis

They act against cancer by phase 2 enzyme induction

Brocolli and cabbage show the greatest protection against bladder cancer

Functional Properties a. Sulfur-Contaning Phytochemicals Isothiocyanates (sulphoraphane), and

dithiolthiones stimulate the activity of enzymes that detoxify carcinogens

It causes cell cycle arrest and apoptosis of cancer cells

It is shown to produce D-glucarolactone, a significant inhibitor of breast cancer

Isothiocyanates present in broccoli may help to reduce the carcinogenic effects of cigarette smoke


Mechanisms to inhibit cancer cells Some produce beneficial changes in gene

expression, thus altering levels of key proteins and enzymes, while others inhibit cell adhesion, spread, and invasion

Scientists have shown that the cruciferous vegetable compound phenethyl isothiocyanate (PEITC) directly inhibits a tumora€TMs ability to supply itself with blood. This interruption of angiogenesis (growth of new blood vessels) is considered an important cancer-fighting mechanism


Sulforaphane is a phytonutrient that stimulates the formation and function of 'phase II' enzymes. These enzymes have been identified as being responsible for processing and removing cancer-causing substances from cells under experimental conditions. It is speculated that these phase II enzymes may be able to perform this function in the human body


Sulforaphane induces cancer cells to commit cellular suicide, while other compounds particularly 13C (Indole-3-carbinol)

or its condensation product diindolyl- methane (DIM) interrupt the ability of cancer cells to reproduce and DIM affected the expression of large number of genes that are related to the control of carcinogenesis, cell survival, and physiologic behaviors


The recent finding of a group of researchers in Johns Hopkins University School of Medicine has confirmed that in laboratory tests, sulforaphane killed Helicobacter pylori, bacteria that cause stomach ulcers and often fatal stomach cancers

They also showed it can kill the bacterium whether it is inside or outside cells


The protective effect of these phytochemicals may arise from their ability to inhibit the carcinogen-activating phase 1 liver enzymes, while inducing the carcinogen-detoxifying phase II enzymes

The critically important phase II enzymes convert dangerous compounds, such as toxins, hormones, and xenoestrogens (estrogen-like compounds from the environment), into less toxic compounds that can safely be eliminated by the body


b. Indoles (Indole-3-carbinol)

This is the most important indole in broccoli. It inhibits the human papilloma virus (HPV), which can cause uterine cancer

It also blocks estrogen receptors in breast cancer cells

It induces cell cycle arrest and apoptosis of breast and prostate cancer cells


The substance indole-3-carbinol (I3C) contained in broccoli and other cruciferous vegetables was found in preliminary research that it affected the metabolism of estrogen in a way that might protect against breast and other female cancers, an idea supported by animal and test tube research

Scientists demonstrated that I3C interferes with breast cancer cell proliferation by altering the size of a protein associated with cellular reproduction. As a result, cellular division grinds to a halt

FUNCTIONAL PROPERTIES I. FLOWER VEGETABLEs

CAULIFLOWER (Brassica oleracea L. var. botrytis L.)



• They act against cancer by phase 2 enzyme induction

a. Sulfur-Contaning Phytochemicals

Isothiocyanates (sulphoraphane), and dithiolthiones stimulate the activity of enzymes that detoxify carcinogens


Sulphoraphane, an isothiocyanate is particularly effective at boosting the activity of enzyme systems that detoxify carcinogens, and it has been shown to protect animals from breast cancer



II. ROOTS ANDTUBERS

CARROTS (Daucus carota L.)


1. Terpenol

Terpenol gives carrot flavor to carrots

It causes cell cycle arrest in cancer cells

2. Carotenoids- Beta-carotene

Beta-carotene's anti-inflammatory effects may reduce the severity of conditions like asthma, osteoarthritis, and rheumatoid arthritis, which all involve inflammation


Large scale studies have shown low blood levels of carotenoids correspond with greater cancer risk

Researchers have found that carotenoids can inhibit the growth of certain types of breast cancer cells, skin cancer cells, lung cancer and stomach cancer (Kiani)


Although epidemiological studies have shown reduced lung cancer incidence among those with high plasma serum levels of beta-carotene, some large intervention studies showed an increased incidence of lung cancer among smokers taking beta-carotene supplements


Beta-carotene is shown to be:

• a weak antioxidant, but strong against

singlet oxygen

• boost the activity of natural killer (NK)

immune cells

• stimulate DNA repair enzymes

• give better cornea protection against

UV light than lycopene


3. Soluble Fiber

This may reduce the risk of coronary heart disease (CHD)

It also reduces both cholesterol and triglyceride levels

II. ROOTS AND TUBERS RADISH (Raphanus sativus L.)

RADISH (Raphanus sativus L.)


1. Isothiocyanates Isothiocyanates are responsible for the hotness of

horseradish, radish and mustard Sulphoraphane, an isothiocyanate is particularly

effective at boosting the activity of enzyme systems that detoxify carcinogens, and it has been shown to protect animals from breast cancer




2. Carotenoids-Beta- carotene

Radish leaves are rich in carotenoids, particularly beta-carotene

Researchers have found that carotenoids in dark green leafy vegetables can inhibit the growth of certain types of breast cancer cells, skin cancer cells, lung cancer and stomach cancer

II. ROOTS ANDTUBERS

SUGAR BEETS/BEETROOT

(Beta vulgaris)


1. Betaine (Trimethylglycine)

Betaine is found in beets

It is capable of removing pro-atherosclerotic protein homocysteine from the body

●An elevated plasma level of homocysteine has long been known as an independent predictor of cardiovascular disease

III. FRUIT VEGETABLES BELL (SWEET) PEPPER (Capsicum annuum L.)


1. P- Coumaric Acid (Para-Coumeric Acid)

Para-Coumeric Acid is high in red and green bell peppers

It is a flavonoid precursor

It is an antioxidant for the colon mucosa. This binds with nitric acid and its derivatives before they combine with protein amines to form nitrosamine


2. Chlorogenic Acid

Chlorogenic acid is very high in tomatoes and bell peppers

It is most frequently an ester of caffeic acid. Caffeic acid reduces mutagenicity of polycyclic aromatic hydrocarbons

It has an antioxidant activity. Caffeic acid can regenerate oxidized Vitamin E


3. Beta-carotene (in red bell peppers)

Beta-carotene’s anti-inflammatory effects may reduce the severity of conditions like asthma, osteoarthritis, and rheumatoid arthritis, which involve inflammation

III. FRUIT VEGETABLES TOMATOES

(Lycopersicon esculentum Mill.)

Functional Properties 1. Carotenoids- Lycopene Lycopene, the carotenoid that gives

tomatoes their red color, is a potent scavenger of oxygen radicals

Studies have shown that the processing of tomatoes and of tomato products, such as sauces, soups and juices, increases the bioavailability of lycopene. The bioavailability from tomato paste is nearly four times greater than from fresh tomatoes

Lycopene accounts for nearly half the total carotenoids in the blood serum

Functional Properties Lycopene

It is a powerful antioxidant which reduces damage to DNA and proteins

It gives better skin protection against UV light than beta-carotene

It is concentrated in the skin, testes, adrenal and prostate where it protects against cancer

It can reduce LDL cholesterol levels

It suppresses insulin-like growth factor (IGF-I) that stimulates tumor growth


Several studies have linked the consumption of tomatoes and tomato products with a decreased risk of these diseases:

1. Lung, bladder, cervix, skin, breast , prostate and colorectal cancers because of their anti-oxidant and anti-proliferative properties

2. Cardiovascular disease, because they may inhibit cholesterol synthesis and enhance LDL (bad cholesterol) degradation

Functional Properties Tomato Bioactive Components and Modes

of Action • Tomatoes contain many bioactive components,

including those that act as antioxidants, such as the vitamins C and E, and many carotenoids

• Lycopene is the most efficient carotenoid at scavenging singlet oxygen and reactive oxygen species

• The antioxidant effect of lycopene is potentially beneficial in disease prevention for both CVD and prostate cancer


In regard to CVD, lycopene and tomatoes could possibly reduce the disease development by reducing inflammation, inhibiting cholesterol synthesis, or improving immune function

The proposed mechanism of action of lycopene in prostate cancer prevention includes inhibition of proliferation, anti-androgen and antigrowth factor effects


Research conducted showed that the lycopene supplemented group had less cancer at the surgical margins and in extraprostatic tissues, smaller tumors, and an 18% reduction in prostate specific antigen (PSA) levels, whereas the control group’s PSA levels increased by 14%

Lycopene treatment was also found to increase expression of connexin 43 in cancerous prostate tissue. Connexin 43 is a recognized tumor suppressor gene, which can increase gap junction communication and therefore suppress overgrowth of cells


2. Chlorogenic Acid

Chlorogenic acid is very high in tomatoes and bell peppers

It has an antioxidant activity

III. FRUIT VEGETABLES SQUASH (Cucurbita maxima)

SQUASH (Cucurbita maxima)



Beta-carotene is an antioxidant which can help reduce oxidative damage done by free radicals in the body

Antioxidant vitamins may prevent or protect against cancer, cardiovascular disease, asthma, pulmonary function problems, diabetes and weight loss

They may also protect eyesight, help protect the brain, and promote gastrointestinal health

III. FRUIT VEGETABLES BITTERMELON

BITTERMELON (MOMORDITA charantia L)


1. Charantin Bitter melon, also known as balsam pear, is a

tropical vegetable has been used extensively in folk medicine as a remedy for diabetes

The blood sugar lowering action of the fresh juice or extract of the unripe fruit has been clearly established in both experimental and clinical studies

Bitter melon is composed of several compounds with confirmed anti-diabetic properties

Charantin, extracted by alcohol, is a hypoglycaemic agent


2. Polypeptide-P or p-insulin

The fruit of bitter melon contains several compounds that contribute to its success: saponins, proteins, and a polypeptide called “p-insulin”

Momordica contains an insulin-like polypeptide, polypeptide-P, which lowers blood sugar levels when injected subcutaneously into type 1 diabetic patients

The oral administration of 50-60 ml of the juice has shown good results in clinical trials


p-insulin

Some scientists suggest that this botanical may help inhibit the absorption of sugar into cells without driving insulin levels to unstable levels (Raman, 1996)

Furthermore, its juice was shown in one study to enhance glucose tolerance in 73% of the participants evaluated

Functional Properties Toxic Effects

Excessively high doses of bitter melon juice can cause abdominal pain and diarrhea

Small children or anyone with hypoglycemia should not take bitter melon, since this herb could theoretically trigger or worsen low blood sugar, or hypoglycemia

Furthermore, diabetics taking hypoglycemic drugs or insulin should use bitter melon with caution, as it may potentiate the effectiveness of the drugs, leading to severe hypoglycemia

IV. LEAFY VEGETABLES CABBAGE

(Brassica oleracea L. var. capitata L)



Glucosinolates convert to isothiocyanates (contain sulfur) and indoles (contain no sulfur) when vegetables containing them are cut

They are high in cruciferous vegetables, particularly cauliflower and cabbage and to a lesser extent in broccoli

They act against cancer by phase 2 enzyme induction. Brocolli and cabbage show the greatest protection against bladder cancer


Glucosinolates may prevent cancer by acting as metabolic detoxicants to facilitate alteration and excretion of cell carcinogens

Glucosinolate-derived indole compounds are inducers of liver and intestinal enzymes that reduced tumor formation in rats

http://www.answers.com/topic/metabolic

http://www.answers.com/topic/excretion

http://www.answers.com/topic/intestinal

http://www.answers.com/topic/tumor


a. Sulfur-Contaning Phytochemicals

Isothiocyanates (sulphoraphane), and dithiolthiones, all contain sulfur in their structure

These classes stimulate the activity of enzymes that detoxify carcinogens


b. Indoles (Indole-3-carbinol).

It inhibits the human papilloma virus (HPV), which can cause uterine cancer

It also blocks estrogen receptors in breast cancer cells

It induces cell cycle arrest and apoptosis of breast and prostate cancer cells


2. Soluble Fiber

May reduce the risk of coronary heart disease (CHD) and reduce both cholesterol and triglyceride levels

Anti-nutrients

Isothiocyanates are goitrogenic in animals and people if consumed in sufficient quantities

IV. LEAFY VEGETABLES RED CABBAGE

(Brassica oleracea L. var. capitata L.)

Functional Properties 1. Glucosinolates

a. Isothiocyanates (sulphoraphane), and dithiolthiones

•Sulphoraphane, an isothiocyanate is particularly effective at boosting the activity of enzyme systems that detoxify carcinogens, and it has been shown to protect animals from breast cancer

•It causes cell cycle arrest and apoptosis of cancer cells. Sulphoraphane is a strong inducer of the phase II enzymes responsible for anticarcinogenic activities

•It shown to produce D-glucarolactone, a significant inhibitor of breast cancer

Functional Properties 2. Flavonoids ( Anthocyanin)

Purple cabbage and other purple-or red-pigmented cole crops contain various anthocyanins

One of the most important types of flavonoids is the anthocyanin, which are pigments that give blue and red colors to blueberries, raspberries, and red cabbage

http://www.answers.com/topic/anthocyanins


2. Flavonoids ( Anthocyanin) These compounds are strong antioxidants

and have anticancer properties and protect against cardiovascular disease by inhibiting the oxidation of LDL cholesterol and affecting platelet function

Flavonoids scavenge free radicals by forming a stable radical that can react with another flavonoid radical to produce two-nonradicals


The phytochemical called anthocyanidins can neutralize free radical damages to the collagen matrix of cells and tissues that can induce glaucoma, peptic ulcers, varicose veins, hemorrhoids, cataracts, heart disease and cancer

Anthocyanins can improve the wholeness of support structures in the veins and the entire vascular system


These are some benefits of flavonoids:

bolsters cellular antioxidant defenses

may contribute to maintenance of brain function

may contribute to maintenance of heart health

neutralizes free radicals

may contribute to maintenance of urinary tract health

IV. LEAFY VEGETABLES LEAF AMARANTH

(Amaranthus viridis L.)


1. Chlorophyll

Chrorophyll is the most abundant pigment in plants

It is the principal light-absorbing pigment in photosynthesis

It forms tight molecular complexes with some carcinogens: aflatoxin-B1, polyaromatic hydrocarbons (tobacco smoke) and heterocyclic amines (cooked meat)

Anti-nutrients

Their moderately high content of oxalic acid inhibits the absorption of calcium and zinc, and also means that they should be avoided or eaten in moderation by people with kidney disorders, gout, or rheumatoid arthritis

Reheating cooked amaranth greens is often discouraged, particularly for consumption by small children, as the nitrates in the leaves can be converted to nitrites, similarly to spinach

http://en.wikipedia.org/wiki/Oxalic_acid

http://en.wikipedia.org/wiki/Kidney

http://en.wikipedia.org/wiki/Gout

http://en.wikipedia.org/wiki/Rheumatoid_arthritis

http://en.wikipedia.org/wiki/Nitrate

http://en.wikipedia.org/wiki/Nitrite

http://en.wikipedia.org/wiki/Spinach

IV. LEAFY VEGETABLES HORESERADISH

(Moringa oleifera Lam)


1. Isothiocyanates

Isothiocyanates are responsible for the hotness of horseradish, radish and mustard

2. Chlorophyll


Functional Properties 3. Carotenoids- Beta-carotene, Lutein

and Xanthin

•Lutein and zeaxanthin constitute about half of all carotenoids in the retina. Lutein and zeaxanthin are the only carotenoids in the macula of the eye

•This is found to protect the eye from macular degeneration and cataracts

It is also shown to protect against colon cancer


4. Flavonoids- Quercetin and Kaempferol

In various epidemiological studies and clinical trials, consumption of quercetin have been associated with a reduced risk of heart disease and improved cardiovascular health

Quercetin and resveratrol provide important synergistic benefits for the heart

IV. LEAFY VEGETABLES LEAF MUSTARD (Brassica juncea L.)


Dark green leafy vegetables include spinach, kale, romaine lettuce, leaf lettuce, mustard greens, collard greens, chicory and Swiss chard are excellent sources of fiber, folate and a wide range of carotenoids which seem to help prevent cancer by acting as antioxidant


1. Isothiocyanates

2. Chlorophyll

• forms tight molecular complexes with some carcinogens: aflatoxin-B1, polyaromatic hydrocarbons (tobacco smoke) and heterocyclic amines (cooked meat)

IV. LEAFY VEGETABLES SPINACH (Spinacia oleracea L.)


1. Carotenoids- Beta-carotene, Lutein and Zeaxanthin

Lutein is in highest concentrations in spinach, watercress and parsely

Lutein and zeaxanthin constitute about half of all carotenoids in the retina. Lutein and zeaxanthin are the only carotenoids in the macula of the eye

This is found to protect the eye from macular degeneration and cataracts



2. Chlorophyll




IV. LEAFY VEGETABLES WATERCRESS Nasturtium officinale R.

Br. (Rorippa nasturtium aqauticum L. Hayek)


1. Phenethyl Isothiocyanate (PEITC)

Phenethyl isothiocyanate gives bitter taste to watercress

It inhibits tumorigenesis by polycyclic aromatic hydrocarbons

It induces apoptosis by caspase-8 activation

It is found to be particularly good against nitrosamines in tobacco smoke (nitric oxide + nicotine → nitrosamine, main carcinogen of tobacco smoke)


Watercress is also known to work against other types of cancer

The majority of cancers are caused by the ingestion/inhalation of potentially carcinogenic compounds which result in genetic disruption of cells, causing them to become cancerous


Certain compounds only become carcinogenic if activated by enzymatic reactions within tissue. This metabolic pathway is often referred to as a phase 1 induction. Free radicals are often produced which in turn initiate phase 2 – a reaction with tissue DNA which can result in uncontrolled replication / tumor development


PEITC has been shown to inhibit phase 1 enzyme activation

Effectively it stops potential carcinogens becoming carcinogenic

Watercress is one of the richest sources of dietary PEITC


There are further metabolic pathways implicated in modulating tumor development

The most relevant in this instance is the ability of certain compounds to cause the selective death of cancerous tissue – known as apoptosis


2. Carotenoid- Lutein and Zeaxanthin

Lutein is in highest concentrations in spinach, watercress and parsely

Lutein and zeaxanthin constitute about half of all carotenoids in the retina

Lutein and zeaxanthin are the only carotenoids in the macula of the eye. This is found to protect the eye from macular degeneration and cataracts



3. Chlorophyll




IV. STEMS AND SHOOTS ASPARAGUS (Asparagus officinalis L.)


1. Rutin

Rutin is in asparagus, buckwheat and citrus fruits

This is found to strengthen capillary walls

Rutin is also with proven protective properties against radiation as well as anti-hemorrhagic effects


2. Anthocyanins

Anthocyanins, which give this variety its purplish color, offer protective properties for the cardiovascular system

Their levels increase as the color deepens, as does the amount of rutin.

It also acts as a precursor of B-group vitamins


3. Saponins

The saponins contained in green asparagus give it its diuretic effect and its high fiber content

It is diuretic because of an acidic substance called asparagine


4. Antioxidants

Asparagus gives important antioxidants like glutathione (other major antioxidants are vitamins A, C, and E, selenium, melatonin, beta carotene, zinc, and pycnogenol)


Antioxidants prevent heart disease, lower cancer risk, help keep bones strong, protect vision and immune system, and improve mental function. More importantly, they keep the skin young

Green asparagus is distinguished by its high levels of the antioxidant vitamins A and C

IV. STEMS AND SHOOTS CELERY

(Apium graveolens L. var. dulce Perr.)


1. 3-n-Butyl Phthalide

Research is showing that the early use of celery as a medicine was not unfounded

3-n-butyl phthalide, one of the components that gives celery its characteristic smell and taste, is especially potent as an anti-tumor agent

Along with the compound sedanolide, an aromatic ingredient also found in celery, 3-n-butyl phthalide significantly reduces the incidence of tumors in laboratory animals


Other studies suggest that this and other phthalides may also help reduce high cholesterol

Even though it's high in sodium (as vegetables do), celery is also proving to be effective at lowering blood pressure because 3-n-butyl phthalide has been demonstrated to relax the smooth muscles that line blood vessels



Carotenoids neutralize free radicals which may damage cells

This also bolsters cellular antioxidant defenses

Some studies have shown that beta-carotene may be an effective ally against prostate cancer


3. Dietary Fiber- Insoluble Fiber

Insoluble fiber contributes to maintenance of a healthy digestive tract

It also lowers the risk of colon and breast cancer

IV. STEMS AND SHOOTS RHUBARB (Rheum rhaponticum L.)


1. Resveratrol

Resveratrol, trans-3,5,4'-trihydroxystilbene, has been found in various plants, including grapes, berries, peanuts and Rheum spp. incl. Rhubarb


Besides cardioprotective effects, resveratrol exhibits anticancer properties, by its ability to suppress proliferation of a wide variety of tumor cells, including lymphoid and myeloid cancers; multiple myeloma; cancer of the breast, prostate, stomach, colon, pancreas, and thyroid; melanoma; head and neck squamous cell carcinoma; ovarian carcinoma; and cervical carcinoma


Resveratrol induces apoptosis Apoptosis is a mode of cell death that

differs from necrosis Apoptosis is characterized by

initiation of cell death from the outside of the cell, necrosis is a death mechanism initiated from inside the cell, primarily from the mitochondria

Figure 1 . Various proposed mechanisms of

apoptosis of tumor cells by resveratrol.

Figure 2. Effect of resveratrol on signaling proteins involved in apoptosis


Resveratrol holds great potential in the prevention and therapy of a wide variety of tumors

Resveratrol has antiproliferative effects through induction of apoptosis in cell lines of various origin such as leukemias and breast, prostate, colon, pancreas, and head and neck carcinomas

Most, but not all, studies indicate that resveratrol does not induce apoptosis in normal cells


Resveratrol has potential for treating diseases other than cancer and cardiovascular ailments

Howitz et al. found evidence in yeast that resveratrol mimics calorie restriction and thus extends the lifespan by 70%

Anti-nutrients and Toxic Effects in Rhubarb

The leaves contain high concentrations of oxalic acid

Oxalic acid can lock up certain minerals (especially calcium) in the body, leading to nutritional deficiency

Cooking the plant will reduce the concentration of oxalic acid

Anti-nutrients and Toxic Effects

People with a tendency to rheumatism, arthritis, gout, kidney stones or hyperacidity should take especial caution if including this plant in their diet since it can aggravate their condition

VI. SEEDS, LEGUMES KIDNEY BEANS,/SNAP BEANS (Phaseolus vulgaricus L.)


1. Phytosterols ( Beta-sitosterol, stimasterol, and campesterol)

Beta-sitosterol has similar structure to cholesterol.

It is the plant equivalent of animal cholesterol

It decreases cholesterol absorption from the GI tract


1. Phytosterols ( Beta-sitosterol, stimasterol, and campesterol)

It also reduces cholesterol manufacture by the liver

It slows cancer cell growth (cholesterol is needed for cell membrane)

Inhibition of epithelial cell division may reduce atherosclerosis

VI. SEEDS, LEGUMES SOYBEANS (Glycine max (L) Merr.


1. Saponins ( Soyasaponins, soyasapogenols)

Saponin binds bile acids and cholesterol in the GI tract to reduce absorption

It is toxic to tumor cells

Found to be effective against colon cancer

It is also an antioxidant


2. Phytoestrogens ( isoflavones such as genistein, biochanin A and daidzein

Besides scavenging free radicals, some phenolic compounds, often referred to as phytoestrogens, appear to interrupt cancer development and affect health by interfering with the action of the hormone estrogen


Phytoestrogens include isoflavones (also a flavonoid) and lignins. These compounds are structurally modified by the microflora in the intestines to form compounds that are similar to estrogen

They are suspected of blocking estrogen function by tying up estrogen receptors on cells


Isoflavones are heterocyclic phenols structurally similar to the estrogenic steroids. Because they are weak estrogens, isoflavones may act as antiestrogens by competing with the more potent, naturally-occurring endogenous estrogens (e.g., 17b-estradiol) for binding to the estrogen receptor

This may explain why populations that consume significant amounts of soy have reduced risk of estrogen-dependent cancer


Isoflavones, the best known of which is genistein, are found in soybeans and are believed to affect hormone-related cancers, including breast and prostate cancer

They are also hypothesized to decrease hot flashes and other symptoms of menopause


Genistein is also found to inhibit tyrosine kinases involved in tumorigenesis

It elevates HDL cholesterol and lowers LDL cholesterol

It is a potent antioxidant against superoxide and hydrogen peroxide

It helps in the prevention of bone resorption (osteoporosis) in post-menopausal women


3. Inositol phosphates ( phytate, inositol, pentaphosphate)

Bind metal ions and prevent them from generating free radicals and protect against cancer

Phytic acid binds minerals, especially calcium and iron. Mineral chelation may reduce free radicals

The iron-binding effect slows cancer growth because cancer cells need iron for growth and reduces cardiovascular disease

This also reduces starch digestion thus lowers blood glucose


4. Protease Inhibitors

Bind to trypsin and chymotrypsin; decrease growth of cancer cells; inhibit malignant changes in cells; inhibit hormone binding; may aid DNA repair which can slow cancer cell division and help return a cell to its normal state; prevent tumors from releasing proteases that destroy neighboring cells


5. Resveratrol Resveratrol is a plant protective phytoalexin

produced by grapes, mulberries, peanuts and soy beans.

This compound occurs in two conformational forms – cis and trans-resveratrol. Trans-resveratrol is the preferred functional form

Trans-resveratrol is thought to improve heart health in a number of ways:

•Laboratory experiments in vitro and studies in animals have shown that trans-resveratrol can stop blood platelets from sticking together (platelet aggregation)


•In one study, scientists investigated the effects of resveratrol on aggregation of platelets isolated from healthy male volunteers

•Trans-resveratrol significantly inhibited the sticking together of blood platelets

• Researchers also induced platelet aggregation in rabbits with high cholesterol and found that when trans-resveratrol was given to the rabbits, the platelets did not stick together

◘ Since sticky platelets are tied to increased risk of heart attack, stroke and blood clots throughout the body, this is a significant finding in regards to life-threatening risk factor


Another of trans-resveratrol’s interesting cardiovascular implications is its ability to enhance angiogenesis, the development of new blood vessels, in order to help feed the heart during periods of oxygen deprivation (ischemia)

The formation of new blood vessels caused by trans-resveratrol restores the blood supply to the ischemic area, preventing heart cell death and abnormal changes to the heart


In addition to being a powerful antioxidant, trans-resveratrol acts like a molecular master key, “opening” or up regulating important genes and functionally related sequences of DNA or “families” of genes that directly control both the lifespan and metabolic efficiency

Trans-resveratrol also stimulates the production of ATP in the mitochondria of muscles


As a key regulatory molecule, trans-resveratrol improves cellular energy production and up regulates the expression of many different genes, leading to metabolic homeostasis as a prerequisite for a long and healthy life


6. Fatty Acids- Polyunsaturated fatty acids and Omega-3 fatty acids- Alpha-Linolenic Acid (ALA)

This may contribute to maintenance of mental and visual functions

Functional Properties 7. Soy protein

Soy protein may have lipid-lowering, antiatherogenic, antioxidant, anticarcinogenic and antiosteoporotic activities. May reduce risk of Coronary Heart Diseases (CHD)

Soy may also benefit bone health.

A clinical study involving postmenopausal women conducted at the University of Illinois (Erdman and Potter, 1997) found that 40 grams isolated soy protein per day (containing 90 mg total isoflavones) significantly increased (approximately 2%) both bone mineral content and density in the lumbar spine after 6 months

Mechanism of Action

Diets rich in soy protein have been found to reduce serum levels of total cholesterol, LDL-cholesterol, triglycerides and apolipoprotein B (apo B)

The mechanism of the lipid-lowering activity of soy protein is unclear

There are a few possible explanations. Soy protein is much richer in L-arginine than is animal protein, which is richer in L-lysine

Some animal studies indicate that dietary increases in L-arginine are accompanied by decreases in cholesterol levels

Mechanism of Action

The soy isoflavones may also contribute to the lipid-lowering activity of soy protein as well as its antiatherogenic activity

Most soy protein products contain the isoflavones genistin, daidzin and glycitin, which have weak estrogenic effects and also may have antiestrogenic activity. Oral estrogens have been shown to decrease total cholesterol and LDL-cholesterol

The soy isoflavones may have similar actions. Interestingly, a few studies have shown that when the isoflavones are removed from the soy protein, the protein itself has little hypocholesterolemic activity

Mechanism of Action

There are also other substances associated with soy protein, including saponins, trypsin inhibitor and bioactive peptides, which may also contribute to the lipid-lowering activity of soy protein. The soy isoflavones are antioxidants, and their antioxidant activity may contribute to the possible anti-atherogenic effect of soy protein.

Mechanism of Action

The antioxidant, anticarcinogenic and antiosteoporotic activities of soy protein are probably due, in large part, to the soy isoflavones

Soy protein has been found to reduce intestinal mucosa polyamine levels in rats, which may be another anticarcinogenic mechanism.

Also, a bioactive peptide has recently been isolated from soybeans and has been found to have potent antimitotic activity

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Nutrients and Health Benefits of Vegetables

Government & Nonprofit

Transcript of Nutrients and Health Benefits of Vegetables