1

Carotenoids, Health Benefits and Carotenoids, Health Benefits and BioavailabilityBioavailability

Carotenoids, Health Benefits and Carotenoids, Health Benefits and BioavailabilityBioavailability

Steven J. Schwartz, Ph.D.Steven J. Schwartz, Ph.D.Food Science & Interdisciplinary Graduate Program in NutritionFood Science & Interdisciplinary Graduate Program in Nutrition

The Ohio State UniversityThe Ohio State University

Presented atPresented atPhytochemicals in Fruit and Vegetable to Improve Human HealthPhytochemicals in Fruit and Vegetable to Improve Human Health

November27, 2007November27, 2007

2

Phytoene

Phytofluene

Lycopene BiosynthesisLycopene Biosynthesis

-Carotene

Neurosporene

Lycopene

Lycopene

-Carotene -Carotene

Biosynthesis of common Biosynthesis of common ββ and and εε cyclic carotenescyclic carotenes

-Carotene

-Carotene -CaroteneAdapted from Britton, 1983 and Gross, 1991.

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Tomatoes Varieties with Unique Carotenoid ProfileTomatoes Varieties with Unique Carotenoid Profile

RED OR1 OR2 YEL GRE

Common CarotenoidsCommon Carotenoids

HydrocarbonsHydrocarbonsXanthophyllsXanthophylls

OH

LuteinLutein --CaroteneCarotene

OH

OH

HO

ZeaxanthinZeaxanthin

HO

--CryptoxanthinCryptoxanthin

--CaroteneCarotene

LycopeneLycopene

Biological Functions of CarotenoidsBiological Functions of Carotenoids

Provitamin A ActivityProvitamin A Activity

NonNon--provitamin A Activity:provitamin A Activity:

•• Singlet Oxygen Quenching ActivitySinglet Oxygen Quenching Activity

•• Antioxidant Activity (Trap Free Radicals)Antioxidant Activity (Trap Free Radicals)

• • Enhancement of Immune ResponseEnhancement of Immune Response

•• Potential Chemopreventive PropertiesPotential Chemopreventive Properties

4

Conversion to Vitamin AConversion to Vitamin A

--carotenecarotene

O2 15,15’-monooxygenase

H+ reductase

retinol

OH

retinol

OH

Carotenoids and Health BenefitsCarotenoids and Health Benefits

EpidemiologicalEpidemiological

Cell cultureCell culture

Animal (experimental)Animal (experimental)

Human (clinical)Human (clinical)

Dietary carotenoids, vitaminDietary carotenoids, vitamin--A, vitaminA, vitamin--C, C, and vitaminand vitamin--E, and advanced AgeE, and advanced Age--related related Macular DegenerationMacular Degeneration

Seddon et al.Seddon et al.J. Am. Med. Assoc. 272: (18) 1413J. Am. Med. Assoc. 272: (18) 1413--1420, 19941420, 1994

“Conclusion.“Conclusion.--Increasing the consumption of foods rich in certain Increasing the consumption of foods rich in certain carotenoids, in particular dark green, leafy vegetables, may decrease carotenoids, in particular dark green, leafy vegetables, may decrease the risk of developing advanced or exudative AMD, the most visually the risk of developing advanced or exudative AMD, the most visually disabling form of macular degeneration among older people.”disabling form of macular degeneration among older people.”

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Lutein & Zeaxanthin in the MaculaLutein & Zeaxanthin in the Macula

•• Macula is the Region Macula is the Region Directly Behind the Lens, Directly Behind the Lens, Receiving the Most LightReceiving the Most Light

Lutein & Zeaxanthin

Receiving the Most Light.Receiving the Most Light.

•• Lutein & Zeaxanthin are Lutein & Zeaxanthin are Deposited Specifically.Deposited Specifically.

•• The Role Is To Prevent The Role Is To Prevent PhotoPhoto--Oxidation. Oxidation. Macula

Lens

Epidemiological Studies Investigating Lutein and Cataract Risk

Study Comparison Outcome

spinach intake1 5 times/week vs. 1 time/month risk 39%pcarotenoid intake2 13.7 vs. 1.1 mg/day of lutein risk 22%carotenoid intake3 7.0 vs. 1.3 mg/day of lutein risk 19%antioxidant intake4 1.3 vs. 0.3 mg/day of lutein risk 50%serum carotenoids5 0.4 vs. 0.18 mol/L of lutein risk 30%

1Handelman, et al., 19882Chasan-Taber, et al., 19993Brown, et al., 19994Lyle, Mares-Perlman, Klein, Klein, Greger, 19995Lyle, Mares-Perlman, Klein, Klein, Palta, Bowen Greger, 1999

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Vegetables, fruit, and cancer prevention: Vegetables, fruit, and cancer prevention: A reviewA reviewSteinmetz KA, Potter JDSteinmetz KA, Potter JD

Journal of the American Dietetic Association 96: (10) 1027Journal of the American Dietetic Association 96: (10) 1027--1039, 19961039, 1996

“The types of vegetables or fruit that most often appear to be “The types of vegetables or fruit that most often appear to be protective against cancer are raw vegetables, followed by allium protective against cancer are raw vegetables, followed by allium vegetables, carrots, green vegetables, cruciferous vegetables, and vegetables, carrots, green vegetables, cruciferous vegetables, and tomatoes.” tomatoes.”

Bioavailability is the fraction of an ingested nutrientthat is available for utilization in normal physiologicalfunctions, metabolism and/or storage.

Absorption and Bioavailability

In the context of this discussion, bioavailability ofcarotenoids is defined as the amount of thesemicronutrients that are absorbed by the intestinalenterocytes and transported in the bloodstream.

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Lack of Improvement in Vitamin A Status with Lack of Improvement in Vitamin A Status with Increased Consumption of DarkIncreased Consumption of Dark--Green Leafy Green Leafy

VegetablesVegetables

dee Pee, S., West, C.E., Muhilal, Karyadi, D. and Hautvast, J.G.A.J. Lancet346: 75-81.

(1995)

“Physical inaccessibility of carotenoids in plant tissues may reduce their bioavailability. It may be difficult to free beta-carotene in dark- green leafy vegetables from its matrix.

Our findings do not support the long-standing assumption that vitamin A deficiency can be combated by increasing the intake of dark-green leafy vegetables. “

(1995)

Food Matrix of Spinach Is a Limiting Factor in Determining the Bioavailability of -Carotene and to a Lesser Extent of Lutein in Humans

(Castenmiller et al. J. Nutr. 129: 349-355, 1999)

ten

e (m

ol/L

)

2.0

2.5

3.0

Se

rum

lute

in (m

ol/L

)

0.4

0.6

0.8

1.0

1.2

Lutein 51%-Carotene

7%

controlcartenoid supplementwhole leaf spinach miced spinachliquefied spinachliquefied spinach plus fiber

Time (days)

-20 0 20 40

Se

rum

to

tal

-ca

rot

0.0

0.5

1.0

1.5

Time (days)

-20 -10 0 10 20 30

S

0.0

0.2

CarotenoidsCarotenoidsCarotenoidsCarotenoids LYMPH

ChylomicronChylomicron

Carotenoid Absorption & MetabolismCarotenoid Absorption & Metabolism

Cleavage Cleavage

Oxidation Oxidation

Isomerization Isomerization

MetabolitesMetabolites PORTAL

MICELLESMICELLES

Adapted from Erdman et al. Ann. N.Y. Acad. Sci. 691:76-85 (1993)

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Plasma Plasma --Carotene Response after Meals Supplemented with Carotene Response after Meals Supplemented with Dietary PectinDietary Pectin (Rock and Swendseid, Am. J. Clin Nutr. 1992)

vels

(m

ol/L

)

2.0

2.5With pectinWithout pectin

Time (hours)

0 50 100 150 200

Pla

sma

B-c

aro

ten

e le

v

0.0

0.5

1.0

1.5

Food Processing and Preparation Food Processing and Preparation

• • Physical and thermal treatment of foods causes Physical and thermal treatment of foods causes degradation of plant cell structural constituents.degradation of plant cell structural constituents.

• • Thermal processing brings about disruption of the Thermal processing brings about disruption of the carotenoid protein complexescarotenoid protein complexescarotenoid protein complexes.carotenoid protein complexes.

• • Inactivation of oxidizing enzymes results in less Inactivation of oxidizing enzymes results in less degradation and greater stability of carotenoids.degradation and greater stability of carotenoids.

• • These changes result in enhanced uptake and efficiency These changes result in enhanced uptake and efficiency of carotenoid absorption.of carotenoid absorption.

60

80

100

120

RAW

PROCESSED

Ch

ange

Ch

ange

Altered “Bioavailability” By Food ProcessingAltered “Bioavailability” By Food Processing

Beta CaroteneCis BetaCarotene

Total BetaCarotene

RAW

PROCESSED0

20

40

PROCESSED

Per

cen

tage

P

erce

nta

ge

AllAll--transtrans

Rock, C., Lovalvo, J., Emenhiser, C., Ruffin, M., Flatt, S., Schwartz, S., Rock, C., Lovalvo, J., Emenhiser, C., Ruffin, M., Flatt, S., Schwartz, S., J. Nutr.,J. Nutr., 128: 913128: 913--916, 1998916, 1998..

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Intake of carotenoids and retinol in Intake of carotenoids and retinol in relation to risk of prostate cancerrelation to risk of prostate cancer

Giovannucci et al.Giovannucci et al.

Journal of the National Cancer Institute, 87(23): 1767Journal of the National Cancer Institute, 87(23): 1767--76, 199576, 1995

“Combined“Combined intakeintake ofof tomatoes,tomatoes, tomatotomato sauce,sauce, andand pizzapizza (which(whichaccountedaccounted forfor 8282%% ofof lycopenelycopene intake)intake) waswas inverselyinversely associatedassociatedwithwith riskrisk ofof prostateprostate cancercancer..””

0.8

0.9

1.0

1.1

Ris

k

0.8

0.9

1.0

1.1

Ris

k

Relative Risk of Prostate Cancer (Non A1) and Intake of Tomato Sauce in the HPFS.

Relative Risk of Prostate Cancer (Non A1) and Intake of Tomato Sauce in the HPFS.

0.4

0.5

0.6

0.7

Rel

ativ

e R

<1 1 2-4 >5Servings per Week

0.4

0.5

0.6

0.7

Rel

ativ

e R

<1 1 2-4 >5Servings per Week

Tomato Saucep, trend = 0.001Tomato Saucep, trend = 0.001

Epidemiological Data: Relative RisksEpidemiological Data: Relative Risks

TotalTotalOralOral

EsophagusEsophagus*Stomach*Stomach

ColonColonR tR t

� Statistically RectumRectum

PancreasPancreas*Lung*Lung

*Prostate*ProstateBladderBladder

BreastBreastCervixCervix

MesotheliomaMesotheliomaRelative Risk: 0 0.5 1.0Relative Risk: 0 0.5 1.0 1.51.5

Significant

� Not Statistically Significant

Giovannucci, 1999

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Carotenoids as AntioxidantsCarotenoids as Antioxidants

Endogenous and ExogenousEndogenous and ExogenousReactive Oxygen Species (ROS)Reactive Oxygen Species (ROS)

AntioxidantsAntioxidants

Lipids, Proteins, DNALipids, Proteins, DNADamageDamage

Chronic DiseaseChronic Disease

Lycopene as a Singlet Oxygen QuencherLycopene as a Singlet Oxygen Quencher

•• Lycopene is the most efficient singlet oxygen quencher and Lycopene is the most efficient singlet oxygen quencher and phenoxyl radical scavenger among the naturally occurring phenoxyl radical scavenger among the naturally occurring carotenoids.carotenoids.

Stahl and Sies, 1996. Lycopene: a biologically important carotenoid for Stahl and Sies, 1996. Lycopene: a biologically important carotenoid for humans? humans? Arch. Biochem. Biophys.Arch. Biochem. Biophys. 336:1336:1--9. 9.

Mortensen and Skibsted, 1997. Importance of carotenoid structure in Mortensen and Skibsted, 1997. Importance of carotenoid structure in radicalradical--scavenging reactions. scavenging reactions. J. Agric. Food Chem.J. Agric. Food Chem. 45:297045:2970--2977. 2977.

Other Hypothesized Mechanism of ActionOther Hypothesized Mechanism of Action

Stimulate enzymes that detoxify toxins/carcinogensStimulate enzymes that detoxify toxins/carcinogens

Enhance DNA repair mechanismsEnhance DNA repair mechanisms

I t i f llI t i f ll Increase apoptosis of cancer cellsIncrease apoptosis of cancer cells

Decrease cell proliferationDecrease cell proliferation

Possess antiPossess anti--angiogenesis activityangiogenesis activity

Restore gapRestore gap--junction communicationjunction communication

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PDA Chromatogram of Tomato Carotenoids

all-trans Lycopene

cis Lycopene

all-trans -Carotene

Selected Geometrical Isomers of LycopeneSelected Geometrical Isomers of Lycopene

allall--trans trans lycopenelycopene

55--cis cis lycopenelycopene

99--cis cis lycopenelycopene

1313--cis cis lycopenelycopene

7,9,9’,7’7,9,9’,7’--ciscis lycopenelycopene

12

360 (cis peak)

C. 464

A. 472

B. 435A. All-trans lycopene

B. Tetra-cis lycopene

C. 13-cis lycopene

LycopeneLycopene

nm250 300 350 400 450 500

CC3030 Analysis of Lycopene Geometrical IsomersAnalysis of Lycopene Geometrical Isomers

Am J Clin Nutr 1997; 66:116Am J Clin Nutr 1997; 66:116--2222

Lycopene is more bioavailable from Lycopene is more bioavailable from tomato paste than from fresh tomatoestomato paste than from fresh tomatoesChristine Gärtner, Wilhem Stahl and Helmut SiesChristine Gärtner, Wilhem Stahl and Helmut Sies

ABSTRACTABSTRACT Lycopene bioavailability, from a single dose of fresh tomatoes or Lycopene bioavailability, from a single dose of fresh tomatoes or tomato paste (23 mg lycopene) ingested together with 15 g corn oil was compared by tomato paste (23 mg lycopene) ingested together with 15 g corn oil was compared by p ( g y p ) g g g p yp ( g y p ) g g g p yanalyzing carotenoid concentrations in the chylomichron fraction. The lycopene isomer analyzing carotenoid concentrations in the chylomichron fraction. The lycopene isomer pattern was the same in both fresh tomatoes and tomato paste. The triacylglycerol pattern was the same in both fresh tomatoes and tomato paste. The triacylglycerol response in chylomicrons was not significantly different after both treatments. Ingestion response in chylomicrons was not significantly different after both treatments. Ingestion of tomato paste was found to yield 2.5of tomato paste was found to yield 2.5--fold higher total and allfold higher total and all--transtrans--lycopene peak lycopene peak concentrations (P<0.05 and P<0.005, respectively) and 3.8concentrations (P<0.05 and P<0.005, respectively) and 3.8--fold higher area under the fold higher area under the curve (AUC) responses (P<0.001) than ingestion of fresh tomatoes. The same was curve (AUC) responses (P<0.001) than ingestion of fresh tomatoes. The same was calculated for lycopene calculated for lycopene ciscis--isomers, but only the AUC response for the isomers, but only the AUC response for the ciscis--isomers was isomers was significantly higher than ingestion of tomato paste (P<0.005). No difference was observed significantly higher than ingestion of tomato paste (P<0.005). No difference was observed in the in the -- and and --carotene response. Thus, in humans, the bioavailability of lycopene is carotene response. Thus, in humans, the bioavailability of lycopene is greater from tomato paste than from fresh tomatoes.greater from tomato paste than from fresh tomatoes.

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Electron MicroscopyElectron Microscopy

Electron micrograph of lycopene crystalloids in mature red tomato chromoplast.

A. Lycopene crystalloids. B. Plastoglobulin-type sacs in which -carotene reportedly accumulates.

3.5 mm

B

A

Tomato Product Consumption Tomato Product Consumption ––Correlation with Plasma LycopeneCorrelation with Plasma Lycopene

Tomato SauceTomato Sauce p < 0.0001p < 0.0001

TomatoesTomatoes p < 0 056p < 0 056TomatoesTomatoes p < 0.056 p < 0.056

Lower Prostate Cancer Risk in Men with Elevated Plasma Lycopene Levels: Results of a Prospective Analysis (Gann et al., Cancer Research, 1999, 59: 1225-1230)

Commercial Products Study Commercial Products Study ––Experimental DesignExperimental Design

Vegetable JuiceVegetable Juice

36 subjects Tomato SauceTomato Sauce

Wash-out Meals Analysis( 14 days) (28 days)

Tomato SoupTomato Soup

18 M, 18F

14

Plasma Lycopene ResponsePlasma Lycopene Response

2.000

3.000

oles

/L

washoutwashout

feedingfeeding

0.000

1.000

umo

sauce soup Veg

Allen et al. J. Nutr. 2003

Total Lycopene Levels in Buccal CellsTotal Lycopene Levels in Buccal Cells

3.0

4.5

JuiceSoupSauce

0.0

1.5

0 1 2 3 4 5 6 7 8Week

Allen et al. J. Nutr. 2003

Time (minutes)

Ab

so

rban

ce

Pre-Treatment

Post-Treatment

0 2000

1.0

Conjugated Diene Formation

(nm

)

Lipoprotein Oxidation Lag Period (min, mean Lipoprotein Oxidation Lag Period (min, mean ±± SE)SE)

CSCS

BaselineBaseline

64.764.7±±2.42.4

TreatmentTreatment

70.170.1±±4.04.0

SignificanceSignificance

p<0.05p<0.05

RTSRTS 64.764.7±±2.42.4 68.368.3±±2.42.4 p<0.05p<0.05

V8V8 64.764.7±±2.42.4 71.771.7±±4.04.0 p<0.01p<0.01

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Two Stage In Vitro DigestionTwo Stage In Vitro DigestionTestTestMealMeal

**

GastricGastricDigestaDigesta

GastricGastricPhasePhase

IntestinalIntestinalDigestaDigesta

IntestinalIntestinalPhasePhase *

Garrett et al. (1999) J. Agric. Food Chem. 47:4301

Centrifugation

DigestaDigesta DigestaDigesta

AqueousMicellarFraction

*

CacoCaco--2 Human Intestinal Cells2 Human Intestinal Cells

Caco-2 CellsTest Media

DMEM +

Micellar Fraction

Uptake Transport

Apical

Basolateral

Harvest CellsAnalyze for Pigments

Collect Basolateral MediaAnalyze for Pigments

4 hours 0-10 hours

16

Carotene Balances on Boys in Rwanda Where Carotene Balances on Boys in Rwanda Where Vitamin A Deficiency is PrevalentVitamin A Deficiency is Prevalent

Roels, Trout and Dujacquier. J. Nutr. 1958

Massive doses of a carotene-rich vegetable to the basic diet over a long period did not greatly increase serum carotene and vitamin A

levels and that most carotene was excreted.

Absorption of Absorption of ββ--Carotene and Vitamin A with Carotene and Vitamin A with Different Levels of FatDifferent Levels of Fat (adapted from Roels et al. J. Nutr.

1958)

200 g carrots(n=5)

200 g carrots+ 20 ml olive oil (n=5)

day β-carotene(µg/100 ml

serum)

Vitamin A(µg/100 ml

serum)

β-carotene(µg/100 ml

serum)

Vitamin A(µg/100 ml

serum)) ) ) )

0 43.0 36.6 47.8 31.0

31 80.6 51.0 297.8 50.4

difference 37.6 14.4 250.0* 19.4

* significantly different from β-carotene serum levels without fat addition(unpaired Student t-test, p<0.005)

Addition of fats to the diet may contribute to the relief of vitamin A deficiency in this region

Roels, Trout and Dujacquier. J. Nutr. 1958

deficiency in this region.

17

CarotenoidsCarotenoidsCarotenoidsCarotenoids LYMPH

ChylomicronChylomicron

Carotenoid Absorption & MetabolismCarotenoid Absorption & Metabolism

Cleavage Cleavage

Oxidation Oxidation

Isomerization Isomerization

MetabolitesMetabolites PORTAL

MICELLESMICELLES

Adapted from Erdman et al. Ann. N.Y. Acad. Sci. 691:76-85 (1993)

a

L

L

6 hour

L

9 hour

PostPost--prandial prandial ResponseResponse

4 hourb

a L

2 hourL

0 hour

440 mV Applied Potential20.0 nA Full Scale

Carotenoid Response at Carotenoid Response at Three Different Lipid Three Different Lipid LevelsLevels

Fat Free 0 gFat Free 0 gReduced Fat 6 gReduced Fat 6 gFull Fat 28 gFull Fat 28 g

Full Fat

Reduced Fat

Fat Free

Brown et al. Am. J. Clin Nutr. In press

(2004)

gg

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Lettuce: 40g, Avocado: 75g, Carrots: 100g, Spinach:80 g

A) Salad

B) Salad with 150g of Avocado

HPLC Chromatograms of TRL Fraction

after Consumption of;

10.0

15.0

20.0

sponse (nA)

10.0 15.0 20.0 25.0 30.0

0.0

5.0

10.0

15.0

20.0

25.0

Retention time (minutes)

Resp

onse

(nA)

87654321

[500 mV]

[440 mV]

[380 mV]

lutein

β- caroteneα-carotene

C) Salad with 24g of Avocado Oil

obtained from the same subject at 5th hour

10.0 15.0 20.0 25.0 30.0

0.0

5.0

Retention time (minutes)

Resp

87654321

[500 mV]

[440 mV]

[380 mV]

10.0 15.0 20.0 25.0 30.0

-5.0

0.0

5.0

10.0

15.0

20.0

25.0

Retention time (minutes)

Res

pons

e (n

A)

87654321

[500 mV]

[440 mV]

[380 mV]

Baseline Corrected Mean AUC Values for Each Treatment

30

40

50

60

L p

lasm

a

alpha-carotene

beta-carotene

lutein

-10

0

10

20

Salad Salad with 75 gavocado

Salad with 150 gavocado

Salad with 24 gavocado oil

nm

ol.h

/L

Values are based upon mean AUC ± SEM

19

Tomato VarietiesTomato Varieties

Postprandial Absorption of Tangerine vs High Lycopene(Pasta Sauce)

60

70

sma

Normalized AUC (Total Lycopene)

0

10

20

30

40

50

nm

ol.h

/L p

las

Tangerine PS Normal HLPS

Accumulating evidence (epidemiological, cellAccumulating evidence (epidemiological, cell--culture, animal and culture, animal and human) continues to associate health benefits with fruit and vegetable human) continues to associate health benefits with fruit and vegetable consumption.consumption.

Carotenoid pigments unique to fruits and vegetables, through Carotenoid pigments unique to fruits and vegetables, through their antioxidant activity, may be important components with their antioxidant activity, may be important components with beneficial physiological propertiesbeneficial physiological properties

SummarySummary

beneficial physiological properties. beneficial physiological properties.

“Bioavailability” of carotenoids from specific food products is “Bioavailability” of carotenoids from specific food products is influenced by a number of dietary factors including food processing influenced by a number of dietary factors including food processing treatments and product formulation (i.e. lipid content) and should be treatments and product formulation (i.e. lipid content) and should be determined to more accurately assess delivery of these phytonutrients determined to more accurately assess delivery of these phytonutrients from the diet. from the diet.

20

Consumption of carotenoid containing F&V’s may have a Consumption of carotenoid containing F&V’s may have a protective effect against oxidative stress in vivo by decreasing protective effect against oxidative stress in vivo by decreasing the susceptibility of lipoproteins to oxidation. the susceptibility of lipoproteins to oxidation.

In vitro assays can be employed to mimic digestion and In vitro assays can be employed to mimic digestion and absorption processes resulting in estimates of in vivo absorption processes resulting in estimates of in vivo bioavailability for carotenoids.bioavailability for carotenoids.

SummarySummary

bioavailability for carotenoids.bioavailability for carotenoids.

Care must be taken not to make the assumption that all the Care must be taken not to make the assumption that all the health benefits brought about by fruit and vegetable health benefits brought about by fruit and vegetable consumption are attributed to a single class of compounds such consumption are attributed to a single class of compounds such as carotenoids.as carotenoids.

ACKNOWLEDGEMENTSACKNOWLEDGEMENTS

•• Steven K. Clinton, M.D., Ph.D.Steven K. Clinton, M.D., Ph.D. Internal Medicine, OSUInternal Medicine, OSU•• Dave Francis, Ph.D.Dave Francis, Ph.D. Horticulture &Horticulture &

Crop Science, OSUCrop Science, OSU•• Mark Failla, Ph.D.Mark Failla, Ph.D. Human Nutrition, OSUHuman Nutrition, OSU•• Cheryl Rock, Ph.D.Cheryl Rock, Ph.D. UC UC -- San DiegoSan Diego

W d Whit Ph DW d Whit Ph D I St t U i itI St t U i it•• Wendy White, Ph.D.Wendy White, Ph.D. Iowa State UniversityIowa State University

•• Minhthy Nguyen, Ph.D.Minhthy Nguyen, Ph.D.•• Charlotte M. Allen, Ph.D.Charlotte M. Allen, Ph.D.•• Mario Ferruzzi, Ph.D.Mario Ferruzzi, Ph.D.•• Nuray Unlu, Ph.D.Nuray Unlu, Ph.D.•• Torsten Bohn, Ph.D.Torsten Bohn, Ph.D.•• Craig Hadley, Ph.D.Craig Hadley, Ph.D.•• Elena Vittadini, Ph.D.Elena Vittadini, Ph.D.

QuestionsQuestions