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American Journal of Lifestyle Medicine
http://ajl.sagepub.com/content/early/2010/11/10/1559827610387488
The online version of this article can be found at:
DOI: 10.1177/1559827610387488
published online 19 November 2010AMERICAN JOURNAL OF LIFESTYLE MEDICINE
Britt Burton Freeman and Kristin Reimers
Tomato Consumption and Health: Emerging Benefits
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American Journal of Lifestyle Medicine
1
Tomato Consumption
and Health: Emerging Benefits
Britt Burton-Freeman, PhD, MS, and Kristin Reimers, PhD, RD
DOI: 10.1177/1559827610387488. Manuscript received April 20, 2010; revised June 1, 2010; accepted June 7, 2010. From the National Center for Food Safety &
Technology, Illinois Institute of Technology, Summit-Argo, IL (BB-F) and ConAgra Foods, Inc., 5 ConAgra Drive, Omaha, NE (KR). Address correspondence to Kristin Reimers,
PhD, RD, Manager, Nutrition and Food Labeling, ConAgra Foods, Inc., 5 ConAgra Drive, Omaha, NE 68102; e-mail: kristin.reimers@conagrafoods.com.
For reprints and permissions queries, please visit SAGE’s Web site at http://www.sagepub.com/journalsPermissions.nav.
Copyright © 2010 The Author(s)
vol. x • no. x
One way to increase vegetable
consumption may be to leverage the
familiarity with, and emerging health
benefits of, tomatoes.
Abstract: Tomatoes and tomato
products are one of the most famil-
iar vegetables in the American diet.
Quantitatively, they are the most con-
sumed nonstarchy vegetable and are
the most significant source of dietary
lycopene; a powerful antioxidant that
has greater bioavailability after cook-
ing and processing (eg, canning).
A large body of research supports an
inverse relationship between consum-
ing tomatoes and tomato products and
risk of certain cancers, while emerging
research is exploring the protective rela-
tionship between tomato intake and a
host of conditions, including cardio-
vascular disease, osteoporosis, ultravi-
olet light–induced skin damage, and
cognitive dysfunction. Initial stud-
ies of tomato consumption and dis-
ease risk reduction focused on lycopene
and antioxidant activity. More recent
hypotheses recognize the advantages of
the whole tomato; and hence, research
on the role of tomato products in health
and disease risk reduction extends
beyond antioxidant function to include
other protective mechanisms such as
antithrombotic and anti-inflammatory
functions. Increasing daily vegetable
intake in the American diet offers the
potential to yield significant health ben-
efits. In addition to the specific benefits
of tomato consumption, encouraging
greater tomato and tomato product
consumption may help increase overall
vegetable intake because of their wide
availability, well-established accept-
ability, cost-effectiveness, and conve-
nience of multiple forms. Leveraging
emerging science about tomatoes and
tomato products may be one simple
and effective strategy to help individu-
als increase vegetable intake, leading to
improved overall eating patterns, and
ultimately, better health.
Keywords: tomatoes; tomato prod-
ucts; cardiovascular disease; cancer; veg-
etable intake; inflammation; antioxidant;
lycopene
Food-based dietary recommenda-
tions are the cornerstone of life-
style approaches to reduce chronic
disease risk. The health benefits of
consuming more fruits and vegetables,
for example, are strongly supported by
scientific evidence; and hence, form
the basis of national policy to promote
health. However, despite the evidence
and widespread initiatives to promote
consumption, fruit and vegetable intake
patterns remain below recommendations.
Therefore, strategies to motivate consum-
ers to consume more fruits and vegeta-
bles require attention.
One way to increase vegetable con-
sumption may be to leverage the
familiarity with, and emerging health
benefits of, tomatoes. Tomatoes and
tomato products are well known by
adults and children alike and have the
unique advantage of meeting consumer
demands on cost, convenience, availabil-
ity, and taste, while delivering a healthful
food option with flexibility for inclu-
sion in a variety of culturally diverse
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American Journal of Lifestyle Medicine XXX • XXX XXXX
dishes. Igniting interest in tomatoes may
increase vegetable consumption directly
as well as improve vegetable consump-
tion in general by prompting individuals
to explore other vegetables for improved
health.
Tomato Overview
Compositionally, the tomato has a
unique nutritional and (phyto)chemical
profile. Vitamin C, vitamin A (as carot-
enoids), fiber, potassium, and the antioxi-
dant lycopene are natural components of
tomatoes.1 Lycopene is the major dietary
carotenoid and tomatoes and tomato-
based foods are the richest sources of
lycopene in the American diet (Table 1).1
Besides tomatoes, lycopene is also found
in watermelon and red grapefruit; how-
ever, tomatoes and tomato products rep-
resent more than 85% of all the dietary
sources of lycopene consumed in the
North American diet.2 Average daily lyco-
pene intake of males and females is
5305 mg, higher than the average daily
intake of all other carotenoids combined
(3388 mg). Lycopene intake is about
3 times that of b-carotene (1742 mg).3
There is a strong relationship between
tomato intake and plasma/serum lyco-
pene concentrations.4-6 Several research
investigations have shown an inverse
relationship between plasma/serum
lycopene concentrations and risk of some
cancers.7-13 Similar associations have been
reported for markers of cardiovascular
disease, osteoporosis, cognitive function,
and body weight.14-21Moreover, relation-
ships between dietary intakes of tomato
products or tomato extract supplements
have been observed in epidemiologi-
cal studies and clinical trials examining
markers of some cancers, cardiovascular
disease, and ultraviolet light–induced skin
erythema.12,22-37
Table 1.
Lycopene Content per Serving in Tomato Products, Tomato-Based Foods, and Fruitsa
Product Serving Size Lycopene (mg)
Tomato paste ¼ cup 18.84
Pasta with meatballs in tomato sauce
canned entree
1 cup 18.14
Tomato sauce ½ cup 17.12
Spaghetti sauce ½ cup 15.82
Minestrone soup 1 cup 15.33
Tomato puree ¼ cup 13.60
Tomato soup 1 cup 13.04
Vegetable juice cocktail ½ cup 11.69
Tomato juice ½ cup 10.98
Stewed tomatoes ½ cup 5.21
Watermelon ½ cup 3.44
Salsa 2 tbsp 3.36
Tomatoes packed in tomato juice ½ cup 3.32
Catsup 1 tbsp 2.51
Raw tomatoes ½ cup 2.32
Grapefruit ½ grapefruit 1.75
a From the US Department of Agriculture National Nutrient Database for Standard Reference,
Release 22.1
Tomato: Fruit or
Vegetable?
Botanically, a fruit is defined
as the ovary that holds the seeds
of a flowering plant. In that con-
text, and with quick visual inspec-
tion, the tomato is undoubtedly
a fruit. Vegetables, on the other
hand, have no foothold on a
botanical definition; any edible
“vegetation” can be called a veg-
etable. The definition of vegeta-
ble in Western diets is driven more
by cultural and culinary tradition
than biology. Vegetables are gen-
erally savory and served as part of
a main course, whereas fruits are
customarily thought to be sweet
and served as a dessert.
Historically, tomatoes were clas-
sified as a fruit. However, when a
tax was levied on imported veg-
etables, but not fruits, the dual
identity of tomatoes became of
significant importance economi-
cally. The case of the tomato def-
inition rose to the Supreme Court,
who ruled in Nix v. Hedden that in
fact tomatoes fit the common def-
inition of vegetables and should
be classified as such. Although
the 1893 Supreme Court ruling
did not change the botanical def-
inition of tomatoes as a fruit, the
savory tomato plays the traditional
role of vegetable in meals, and is
classified as a vegetable by the US
Department of Agriculture.
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Lycopene
Lycopene is a carotenoid pigment prin-
cipally responsible for the characteristic
deep-red color of ripe tomato fruits and
tomato products. All carotenoids posses
a polyisoprenoid structure, a long con-
jugated chain of double bonds, and a
near bilateral symmetry around the cen-
tral double bond (Figure 138).39 Different
carotenoids are derived by modifications
in the base structure by cyclization of the
end groups and by introduction of oxy-
gen giving them their specific colors and
antioxidant properties.40 Unlike some
carotenoids, lycopene lacks the termi-
nal b-ionic ring and thus does not have
provitamin A activity.40 Because of the
high number of conjugated dienes within
lycopene, its potency as an effective sin-
glet oxygen quencher is about 2 times
greater than b-carotene and 10 times
greater than vitamin E.41,42 As one of the
most potent antioxidants in food, lyco-
pene has attracted the interest of scien-
tists and health professionals alike for its
potential to reduce disease risk and pro-
mote health.
Lycopene exists in foods primarily
in the trans sterisomeric configuration;
however, cooking and processing help
convert trans-lycopene to cis-lycopene,
which is more readily absorbed.43,44
Lycopene is found in appreciable levels
in human serum and tissues when toma-
toes and tomato products are consumed
frequently. In addition to lycopene, toma-
toes also contain other carotenoids,
including phytoene, phytofluene,
z-carotene, g-carotene, b-carotene, euro-
sporene, and lutein. These carotenoids
have also attracted attention for bene-
fiting health.45 Thus, in addition to their
culinary role in the diet, tomatoes rep-
resent a low energy dense food with
unique constituents that may positively
affect health.
Lycopene Versus
Tomatoes
As data linking tomato intake with dis-
ease risk reduction have multiplied,
investment in determining the responsi-
ble tomato components has expanded.
Identifying lycopene as a principal bio-
active component of tomatoes has
spawned hundreds of research investi-
gations to determine its potential mecha-
nisms of action. In addition to lycopene’s
well-documented antioxidant potency,
evidence is accumulating to suggest
that it also can modulate intercellular
gap junction communication and hor-
monal, immune system, and metabolic
pathways.46
The safety and efficacy of lycopene
supplementation has received consider-
able attention. Lycopene supplementa-
tion in prostate cancer patients has been
shown to be safe and well tolerated in
Note: Reprinted with permission from Caledonian Science Press Ltd.
Figure 1.
Chemical Structures of Dietary Carotenoids.
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American Journal of Lifestyle Medicine XXX • XXX XXXX
doses up to 120 mg/d for up to 1 year.47
Clark et al47 also showed that peak con-
centrations of lycopene were achieved in
3 months, reaching a plateau that did not
differ significantly among doses of 15 to
90 mg/d. Evidence for improving disease
status among lycopene supplementation
studies ranging in dose (15-120 mg/d)
and duration (3 weeks to 1 year) is
equivocal, as measured by changes in
insulin-like growth factor (IGF)-1,
including IGF binding proteins,27,48-50
prostate-specific antigen,47,51-55 and benign
prostate hyperplasia.51,55 In contrast, data
consistently support a protective relation-
ship between tomatoes and tomato prod-
uct intake and prostate cancer risk as
well as improvements in markers of dis-
ease status.28-30,56-59
Similarly, research suggests that lyco-
pene supplementation for lowering car-
diovascular disease risk is safe and well
tolerated. Reduced blood pressure after
lycopene supplementation was reported
in 2 studies32,60 out of 3 available stud-
ies.32,60,61 To our knowledge, tomatoes’/
tomato products’ effect on blood pressure
have not been reported. Several supple-
mentation investigations examined the
antioxidant effects of lycopene and toma-
toes. Results consistently show improved
antioxidant status with tomato/tomato
products consumption and after lyco-
pene supplementation33,50,62; however, 2
large clinical trials of lycopene supple-
mentation reported neutral effects on oxi-
dative stress markers.45,63 Similar large
randomized controlled trials on tomato
intake and oxidative stress markers have
not been reported. However, one study
(n = 60) in relatively healthy individu-
als33 and 2 studies (n = 40 and n = 57) in
individuals with type 2 diabetes, who are
in a relatively pro-oxidant state, showed
decreased lipid peroxidation rates64 and
decreased susceptibility of low-density
lipoproteins (LDL) to oxidation35 after
daily consumption of tomatoes or tomato
juice. Others have reported less suscep-
tibility to oxidation of DNA65,66 and LDL67
after tomato product consumption deliv-
ering approximately half (or more) of
the lycopene dose typically used in lyco-
pene supplementation studies. These
data suggest that the health benefits of
tomato/tomato product consumption are
not solely because of lycopene content,
but rather the result of the combination of
nutrients and bioactive constituents deliv-
ered when the whole food is consumed.
These data underscore recommendations
for “food first” approaches to health and
improved quality of life.
Cancer
The majority of research conducted in
the area of tomato and lycopene intake
and cancer risk has been observational.
The difficulty posed in studying the effect
of an intervention to reduce risk of can-
cer is that acceptable and validated study
endpoints include incidence of the can-
cer itself; or in the case of colon cancer,
recurrent colon or rectal polyps in oth-
erwise healthy people.68 Because cancer
often takes decades to present, conduct-
ing randomized, controlled clinical tri-
als with these endpoints is generally not
feasible. Instead, observational studies of
populations showing associations but not
cause and effect have been the primary
source of knowledge on tomatoes/tomato
products and cancer. In a recent review
of the literature, 178 original research
articles were compiled reporting findings
in humans on the relationship between
lycopene, tomatoes and tomato-based
products, and cancer risk.69 Among these
publications, nearly 90% were observa-
tional, highlighting the paucity of cause
and effect investigations in this area.
Reports on 13 cancer types were identi-
fied, of which breast, colorectal, gastric/
upper gastrointestinal, and prostate can-
cers have the most original research pub-
lished in humans, ranging from 17 to
60 publications. For breast, colorectal,
and gastric cancers, the data support a
neutral, although potentially protective,
relationship between tomato/lycopene
intake and cancer risk. Although the data
are limited for gastric and lung cancers;
the protective association is strongest
with tomato intake verses dietary lyco-
pene intake.
Among the cancers investigated rela-
tive to lycopene and tomato intake, pros-
tate cancer is the most widely researched.
Although randomized controlled trial data
are less available than observation data,
a small number of dietary intervention
trials using processed tomato products
have been conducted. The results have
been relatively successful as measured by
improvements in prostate-specific antigen
concentrations26,29,59,70 or increased apop-
totic cell death in carcinomas.30 Of note,
these trials vary in quality, have small
sample sizes, use biomarkers instead of
cancer as the outcome, and use people
already presenting with disease. Validated
cancer markers and larger clinical trials in
at risk populations are warranted to better
understand the cause and effect relation-
ship between lycopene, tomatoes and
tomato products, and cancer.
Cardiovascular Disease
The research examining tomatoes and
cardiovascular disease (CVD) is emerg-
ing as the etiology of CVD expands from
a basic lipid storage disease to include
endothelial dysfunction, severe inflamma-
tion, and oxidative damage. Tomatoes,
with their distinctive nutritional attributes
may play an important role in reduc-
ing the risk of cardiovascular and asso-
ciated diseases through their bioactivity
in modulating disease process pathways.
In 2004, Sesso et al18 reported an inverse
association for women consuming greater
intakes (>7 servings per week) of tomato-
based products and CVD; an associa-
tion not observed with lycopene intake
alone.18
Several hypotheses are being tested
related to the antioxidant properties of
lycopene and a combination of carot-
enoids with coexisting water-soluble con-
stituents delivered by tomatoes, such as
vitamin C. The antioxidant capacity of
plasma decreases when tomatoes and
tomato products are removed from the
diet and increased when they are added
back.33 Consuming tomato products daily
for 2 to 4 weeks increases antioxidant
enzyme defenses and has been shown
to reduce plasma lipid peroxides and the
susceptibility of LDL to oxidation.31,35,71
Oxidative modification of LDL is a key
step in the development of atheroscle-
rotic lesions.72 Consuming diets with
appreciable amounts of antioxidants from
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5
plant foods, such as tomatoes, to inhibit
the oxidative process of LDL may be one
way to reduce the risk of cardiovascular
atherosclerotic disease.
Tomatoes and tomato products are
also being investigated for possible anti-
inflammatory, antithrombotic, and lipid-
lowering effects. Supplementation of a
low tomato diet with tomato products
produces mixed results as measured by
changes in inflammatory markers such as
C-reactive protein (CRP), interleukin-6,
and tumor necrosis factor-a. Jacob et al34
reported decreased CRP after a 2-week
tomato juice supplementation containing
approximately 21 mg lycopene and
2 levels of vitamin C (45.5 mg and 435 mg,
respectively). Both juices reduced CRP
as well as total cholesterol concentration.
In contrast, others have reported neu-
tral effects on inflammatory markers after
juice supplementation73,74 as well as on
lipid profile.64,75 To date, research describ-
ing the potential benefits of tomatoes and
tomato products on inflammation and
immune function is limited. However, this
remains an important underinvestigated
area of research. Future work will signifi-
cantly contribute to our understanding of
the role of tomatoes in inflammation and
immune function related to CVD.
Natural antithrombotic agents that
influence platelet function or fibrino-
lytic activity are of interest as primary
and secondary cardiopreventive strat-
egies. Aqueous extracts from tomatoes
have been shown to display antiplate-
let activity in vitro.76 Subsequent research
in humans shows significant reductions
in ex vivo platelet aggregation 3 hours
after supplementation with tomato extract
from the yellowish membrane surround-
ing seeds in amounts equivalent to 2 or
6 fresh tomatoes.77
Emerging Areas: Skin,
Bone, and Brain Health
Research in cancer and cardiovascular
disease, particularly related to the anti-
oxidant effects of tomatoes, has lead to
research in other areas where oxidative
stress and damage play significant roles
in disease etiology. Skin protection, bone
and brain health are attracting attention
for a possible role of tomato products.
Although the human literature is far from
replete in these areas, promising results
have been reported. For skin protection,
tomato intake (40 g tomato paste corre-
sponding to a lycopene dose of approx-
imately 16 mg) for more than 8 weeks
reduced ultraviolet light–induced ery-
thema.36,37,78 Epidemiological studies sug-
gest a beneficial relationship between
dietary sources of lycopene and bone
mass.79-81 Likewise, lower serum lycopene
concentrations have been documented in
osteoporotic women compared with
controls.19,20 Rao et al17 have also reported
an inverse association between serum
lycopene and markers of oxidative
stress and bone turnover in 33 post-
menopausal women aged 50 to 60 years.
Research for a possible role of toma-
toes in brain health has largely been lim-
ited to case–control studies investigating
the relationship between plasma/serum
lycopene and oxidative stress markers
in people with documented Alzheimer’s
disease, Parkinson’s disease, vascular
dementia, and mild cognitive impairment
compared with control/noncognitively
impaired individuals. In general, plasma/
serum lycopene concentrations are lower
in cognitively impaired compared with
control individuals14-16,82 and oxidative
stress markers are elevated and inversely
correlated with plasma carotenoids
concentrations.14,15,83
Tomato Processing:
Does It Increase the
Nutritional Benefits?
Raw fruits and vegetables are typically
touted as superior to their processed
(ie, canned and frozen) counterparts.
However, in the case of tomatoes, pro-
cessing adds value by increasing the
availability of lycopene for absorption.
Several studies have shown that a higher
serum lycopene concentration is corre-
lated with lower cancer risk,9,11-13
CVD risk,2,18,33,40,69 and osteoporosis.20
Processing assists with lycopene’s bio-
availability by softening cell walls, mak-
ing lycopene in tomato tissues more
accessible, and by converting some of the
trans-isomers of lycopene to cis-isomers.84,85
Cis-lycopene stereoisomers are more bio-
available than the trans-isomer, which
is primarily found in raw, ripe toma-
toes.43,44,86-90 Cis-isomers are more read-
ily absorbed through the intestinal wall
into the plasma because of the greater
solubility in micelles, preferential incor-
poration into chylomicrons, less ten-
dency to aggregate and crystallize, more
efficient volatilization in lipophilic solu-
tions, and easier transport within cells,
across plasma membranes, and the tis-
sue matrix.43,91 The greatest increase in
cis-isomer formation occurs when tomato
products are heated at very high temper-
atures. Likewise, lycopene bioavailabil-
ity increases in the presence of oil.89,90,92,93
Whether oil needs to be present in the
tomato product during thermal process-
ing to solubilize and free the lycopene
from its matrix to enhance isomerization
is still uncertain.44 In summary, processed
tomato products have enhanced bioavail-
ability of lycopene due in part to heat
applied in cooking and processing meth-
ods and the addition of small amounts of
fat or oil.
Reaching Vegetable
Consumption Goals
The emerging research on tomatoes
exemplifies the health benefits of con-
suming adequate amounts of fruits and
vegetables as encouraged in federal pub-
lic health policy and Food and Drug
Administration (FDA) regulation.94,95 In
all, 3 of the 12 original authorized FDA
Health Claims for food labels pertain to
fruits and vegetables and reduced risk of
cancer and CVD (21 CFR 101.76, 101.77
and 101.78).95
The mechanism by which tomatoes
and other fruits and vegetables decrease
risk of disease is complex and largely
unknown. Various components of the
whole food are likely to contribute to
the overall health benefit. Components
with antioxidant properties, such vitamin
C and carotenoids may work directly by
quenching free radicals or indirectly by
participating in cell signaling pathways
sensitive to redox balance. Nutrients such
as potassium contribute to blood pres-
sure regulation. The fiber content and
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American Journal of Lifestyle Medicine XXX • XXX XXXX
type of different fruits and vegetables
may also contribute to the overall health
benefit, such as improving bowel tran-
sit, lowering cholesterol, and helping
manage blood glucose concentrations.
Finally, increasing fruits and vegetables
in the diet may reduce the intake of sat-
urated fats, trans fats, and foods with
higher caloric density; all of which may
be related to a healthier overall diet.
Over the past 50 years, the US Depart-
ment of Agriculture–recommended daily
amount of vegetables has gradually
increased from 2 servings in 1956 to
5 servings (2½ cups) currently. Despite
these recommendations and the scien-
tific evidence supporting the benefits of
eating more vegetables, Americans fall
short of incorporating adequate vegeta-
bles into their daily diets. The National
Cancer Institute’s Usual Dietary Intakes
report indicates that adult Americans’
median vegetable consumption is about
1½ cups daily, compared with the recom-
mended 2½ cups of vegetables daily for
a 2000-calorie diet. Approximately 90%
of adults fall short of the recommended
amount.96
National efforts to promote higher veg-
etable intake have been implemented.
Increasing vegetable intake continues to
be a goal in the US Department of Health
and Human Services’ Healthy People
2020. The National Cancer Institute has
driven this initiative, initially with 5
a Day, and more recently with Fruits
and Vegetables More Matters campaign.
Data indicate that these efforts have not
had a measurable effect on vegetable
consumption.97
Many barriers have been identified that
inhibit the intake of vegetables—lack of
availability of raw produce, cost, bitter or
unpleasant flavor, and unfamiliarity, to
name a few. Tomato products are one of
the few non-starchy vegetables that cir-
cumvent these barriers. In fact, toma-
toes are second only to potatoes in total
consumption by Americans.98 Tomatoes
account for 22% of total vegetable con-
sumption; approximately 86 pounds
(mostly canned tomato products) are con-
sumed per capita per year (Figure 2).98,99
Thus, the variety and availability of toma-
toes and tomato products, as well as
their culinary and cultural adaptability,
increases the potential of focusing atten-
tion on tomato consumption as a feasi-
ble strategy to help Americans meet the
challenging goal of increased vegetable
consumption.
An “Other” Vegetable?
USDA classifies vegetables into 5 sub-
groups, each with unique nutrient con-
tributions Dark Green, Orange, Starchy,
Legumes and Other. The Other Vegetable
subgroup provides 55% of the total veg-
etable intake, of which tomatoes account
for 39%. As shown in Figure 3, intakes of
Dark Green, Orange, and Legume sub-
groups fall well below recommendations.
For example, the recommended intake
of Orange Vegetables is 2 cups a week,
and current consumption is 0.29 cups a
week, about 15% of the recommended
0%
10%
20%
30%
40%
50%
60%
Raw Canned sauces, paste
& whole tomatoes
Juice Ketchup
Figure 2.
Distribution of Tomato and Tomato Products Consumption.
Source: Economic Resource Service.98,99
0%
20%
40%
60%
80%
100%
120%
140%
Dark
Green
Orange Legumes Starchy Other
Female Adults
Male Adults
Figure 3.
Usual Intake as a Percentage of Recommended Intake for Vegetable
Subgroups.
Source: US Department of Agriculture.94,96
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American Journal of Lifestyle Medicinevol. X • no. X
7
amount for a 2000-calorie diet.94,96 Given
the distinctive nutritional profile of toma-
toes, and the emerging yet robust body
of research showing health support-
ing attributes of tomatoes, placing toma-
toes in the generic other category misses
an opportunity to highlight tomatoes as a
positive selection for Americans who are
trying to improve their diets. Elevating
the profile of tomatoes by creating a new
vegetable subgroup called Red-Orange
to include tomatoes is recommended by
the 2010 Dietary Guidelines Advisory
Committee.100 The addition of “red” to
this subgroup will add nutritional value
to the category, and featuring the famil-
iar tomato in the Red-Orange Vegetable
subgroup may increase exposure to other
vegetables in this category as well as
make it more feasible for Americans to
meet the weekly intake recommendation
from this subgroup for health promotion.
Potassium
In addition to lycopene, tomatoes are
one of the top contributors of potas-
sium to the American diet. Based on
1999-2000 National Health and Nutrition
Examination Survey food intake data,
tomatoes rank seventh after milk, pota-
toes, beef, coffee, poultry, and orange/
grapefruit juice as a potassium source.101
Potassium is a nutrient of concern, as
most Americans consume amounts well
below the Dietary Reference Intake
(DRI). In 2004, the new adult DRI for
potassium (4700 mg) was substan-
tially higher than the amount previously
reported in the 1989 Recommended
Dietary Allowance (3500 mg).102,103 The
increased recommendation was based on
evidence indicating that 4700 mg potas-
sium should help lower blood pressure,
reduce the adverse effect of excess
sodium intake on blood pressure, reduce
the risk of kidney stones, and possibly
reduce age-related bone loss. Meeting
potassium intake recommendations is
challenging when consuming a typi-
cal American diet. To increase potassium
intake without increasing calorie intake,
calories currently consumed as solid
fats, added sugars, and alcohol will need
to be replaced in part by foods rich in
potassium. Table 2 shows the potassium
content per 100 kcal of the top potassium
sources. Tomatoes provide at least twice
the potassium per 100 kcal compared
with other common sources, except
coffee, a nonsignificant calorie source of
potassium. Consuming potassium from
fruits and vegetables is ideal because it
occurs with a biologically advantageous
ratio of bicarbonate or citrate, important
for bone health. Increasing potassium
intake through increased tomato intake
is a healthful, calorically sensible strategy
for Americans.
Summary and
Conclusions
Tomatoes are quantitatively the most
important nonstarchy vegetable in the
American diet. They offer significant
nutritional advantages, including provid-
ing a significant source of dietary lyco-
pene and other carotenoids, vitamin C,
potassium, and fiber in a low energy
dense food. Emerging research under-
scores the relationship between consum-
ing tomatoes and tomato products with
reduced risk of certain cancers, heart dis-
ease, ultraviolet light–induced skin dam-
age, osteoporosis, and other conditions.
Although lycopene has been extensively
investigated apart from the tomato, the
preponderance of evidence suggests that
consumption of whole tomatoes and
tomato products should be preferen-
tially recommended because of greater
consistency of documented positive out-
comes with the whole tomato and the
concomitant supply of other important
essential nutrients and nonessential nutri-
ent-like bioactive substances. In addi-
tion to the specific nutritional benefits of
tomato consumption, encouraging greater
tomato and tomato product consumption
may be a simple and effective strategy
for increasing overall vegetable intake.
Tomatoes are widely available, have an
established record of acceptability among
people of all ages and across cultures,
are cost-effective, and offer the conve-
nience of multiple forms. These factors
increase the likelihood for compliance
and high potential for improving overall
dietary patterns in general.
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Coffee 116 (per 8-oz serving)
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