| Nutritional Facts and Health Benefits of Spinach |
NUTRITIONAL VALUE OF SPINACH
Spinach is believed to be of Persian origin and introduced into
Europe in the 15th century. Since the early 19th century,
spinach has been a versatile and commonly used vegetable in
the United States. Spinach is so popular because of its taste,
nutritional value and potential health benefits. It contains low
calories, potassium, sodium, protein, iron, calcium, fibers,
vitamins A and C.
POTENTIAL HEALTH BENEFITS OF SPINACH
Spinach leaves, containing several active components, including
flavonoids, exhibit antioxidative, antiproliferative, and
antiinflammatory properties in biological systems. Spinach
extracts have been demonstrated to exert numerous beneficial
effects, such as chemo- and central nervous system protection
and anticancer and anti-aging functions.
Extracts of spinach leaves show high anti-oxidative activities
and are well tolerated in animal studies. No side effects are
reported in these animal studies. [1]
Spinach may have benefits of cutting cancer risks.
Japanese researchers proposed to use spinach extracts as
anticancer agent. They found that spinach contained a large
amount of sulfoquinovosyl diacylglycerol and this compound is a
potent inhibitor for certain human cancer cell proliferations. Of
the six subspecies of spinach (Spinacia oleracea) tested, "Anna"
had the largest amount of sulfoquinovosyl diacylglycerol,
strongest inhibitory activity toward DNA polymerase and
greatest effect on human cancer cell proliferation. Other plants
containing this compound include parsley, green onion, chive,
sweet pepper, green tea, carrot and garlic. [2]
Longnecker MP et al from National Institute of Environmental
Health Sciences observed the association between intake of
fruits, vegetables (such as carrots, spinach), vitamin A and
lower risk of breast cancer in some studies. [3]
Spinach may have benefits in neurodegenerative diseases.
Researchers from United States Department of Agriculture
reported six-month-supplementation of spinach (6.4 g/kg DEA)
was linked to significant retardation of age-effects on
neurodegenerative diseases in a study of 344 rats. [4]
Researchers from National Institute on Drug Abuse have shown
that treatment with diets enriched with blueberry, spinach, or
spirulina reduced neurodegenerative changes in aged animals.
They further demonstrated that chronic treatment with
blueberry, spinach, or spirulina reduces
ischemia/reperfusion-induced apoptosis and cerebral infarction
in a study of Sprague-Dawley rats. [5]
Researchers from University of South Florida reported 6 weeks
of a spinach-enriched diet ameliorated deficits in
cerebellar-dependent delay classical eyeblink learning and
reduced the proinflammatory cytokines tumor necrosis factor
alpha (TNFalpha) and TNFbeta in the cerebelli of eyeblink-trained
animals. Old animals on the spinach-enriched lab chow diet
learned delay eyeblink conditioning significantly faster than old
animals on the regular diet. [6]
Aging is associated with a decline in motor coordination and the
ability to learn new motor learning skills. This loss of function is
correlated with a decline in cerebellar beta-adrenergic receptor
function.
Researchers from University of Colorado Health Sciences Center
examined the role of oxidative stress on this system by
exposing young rats to normobaric hyperoxia. This exogenous
oxidative insult resulted in a decline in cerebellar
beta-adrenergic receptor function that resembleed what was
observed in normal aged rats. This effect of hyperoxia was
blocked by antioxidants. They also examined the effects of
nutritional supplementation of aged rats with diets high in
antioxidant capacity. They concluded that foods such as
blueberries and spinach can prevent and/or reverse age-related
declines in cerebellar noradrenergic receptor function. [7]
Bickford PC et al, Boston, explained that reactive oxygen
species are involved in the decline in function associated with
aging. Spinach diets or supplements containing antioxidants
reverse age-induced declines in beta-adrenergic receptor
function in cerebellar Purkinje neurons; benefit age-related
deficits in motor learning and memory. In addition, motor
learning is important for adaptation to changes in the
environment and is thus critical for rehabilitation following
stroke, spinal cord injury, and the onset of some
neurodegenerative diseases. [8]
In sum, increasing dietary intake of fruits and vegetables (such
as spinach) high in antioxidant activity may be an important
component of a healthy living strategy designed to maximize
neuronal and cognitive functioning into old age. [9]
Spinach may have benefits of heart protection.
We know that doxorubicin produces clinically restorative
responses in numerous human cancers, but its cardiotoxicity
has limited its usefulness. Israeli researchers evaluated the
prophylactic effect of spinach natural antioxidant on doxorubicin
-induced cardiotoxicity and oxidative stress in female Balb/c
mice. They found that pretreatment with spinach natural
antioxidant before doxorubicin administration decreased
catalase and increased superoxide dismutase activities
compared to the doxorubicin group. [10]
Eating Spinach
Eating and preparing spinach is simple and easy, since it tastes
good raw or cooked. Spinach can be found fresh, frozen, or
canned; it can be easily incorporated into many dishes. Its
versatility makes it easy to serve raw in salads or sandwiches or
as a complement to soups, meat, fish, or other vegetable
dishes.
At the supermarket, you can find spinach packaged fresh,
canned, or frozen. Fresh spinach is usually found loose or
bagged. For the best quality, select leaves that are green and
crisp, with a nice fresh fragrance. Avoid leaves that are limp,
damaged, or spotted. If you are in a rush, grab a bag of fresh,
pre-washed spinach. The ready-to-eat packaging makes it easy
to be on the go and still stay healthy.
Fresh spinach should be dried and packed loosely in a
cellophane or plastic bag and stored in the refrigerator crisper.
If stored properly, it should last 3 or 4 days.
Spinach grows in sandy soil, so wash it thoroughly to get rid of
the grainy, sandy particles. Make sure to tear off the stem.
Separate the leaves, and place them in a large bowl of water.
Gently wash leaves, and let the sand drift to the bottom of the
bowl. Remove leaves from the water, and repeat the process
with fresh water until the leaves are clean.
If spinach is to be eaten raw, dry it completely by using a salad
spinner or by blotting it with paper towels. Slightly damp
spinach can be steamed or microwaved without adding any
additional water.
Blanching Drop leaves into a large pot of boiling water. Once
the leaves slightly wilt, drain and squeeze out excess moisture.
This method is used to quick-cook spinach or to prepare it for
sautéing, braising, or stuffing, and usually takes 2 to 5
minutes.
Microwaving This method can be used instead of blanching.
Place washed, slightly wet spinach in a microwavable dish,
loosely cover, and cook until tender (4 to 7 minutes for ½
pound of spinach).
Sautéing Blanched spinach can be sautéed quickly with a
quick spray of oil. If cooked in a non-stick pan, only a spray is
needed for several cups of chopped spinach. Try adding some
garlic for flavor.
Steaming If you plan to steam the spinach, do not dry leaves
after washing. Steamed spinach makes a great side dish and
usually takes only 5 to 10 minutes.
Tips to improve iron and calcium absorption from
spinach
Preparation Iron and calcium in plant foods are not highly
absorbed by the body. Spinach contains a chemical called oxalic
acid, which binds with iron and calcium and reduces the
absorption of these minerals. To improve iron absorption,
spinach should be eaten with vitamin C-rich foods such as
orange juice, tomatoes, or citrus fruit.
THIS ARICLE IS FOR YOUR REFERENCE ONLY. CONSULT YOUR DOCTOR IF YOU
HAVE ANY QUESTIONS. ALL RIGHTS RESERVED 2006 ZHION
REFERENCE: [1] Lomnitski L, et al, Composition, efficacy, and safety of spinach
Nutr Cancer. 2003;46(2):222-31.extracts. [2] Kuriyama I, et al, Inhibitory effects
of glycolipids fraction from spinach on mammalian DNA polymerase activity and
human cancer cell proliferation. J Nutr Biochem. 2005 Oct;16(10):594-601. [3]
Longnecker MP, et al, Intake of carrots, spinach, and supplements containing
vitamin A in relation to risk of breast cancer. Cancer Epidemiol Biomarkers Prev.
1997 Nov;6(11):887-92. [4] Joseph JA, et al, Long-term dietary strawberry,
spinach, or vitamin E supplementation retards the onset of age-related neuronal
signal-transduction and cognitive behavioral deficits. J Neurosci. 1998 Oct
1;18(19):8047-55. [5] Wang Y, et al, Dietary supplementation with blueberries,
spinach, or spirulina reduces ischemic brain damage. Exp Neurol. 2005
May;193(1):75-84. [6] Cartford MC, et al, Eighteen-month-old Fischer 344 rats
fed a spinach-enriched diet show improved delay classical eyeblink conditioning
and reduced expression of tumor necrosis factor alpha (TNFalpha ) and TNFbeta
in the cerebellum. J Neurosci. 2002 Jul 15;22(14):5813-6. [7] Bickford PC, et al,
Effects of aging on cerebellar noradrenergic function and motor learning:
nutritional interventions. Mech Ageing Dev. 1999 Nov;111(2-3):141-54. [8]
Bickford PC, et al, Antioxidant-rich diets improve cerebellar physiology and motor
learning in aged rats. Brain Res. 2000 Jun 2;866(1-2):211-7. [9] Galli RL, et al,
Fruit polyphenolics and brain aging: nutritional interventions targeting
age-related neuronal and behavioral deficits. Ann N Y Acad Sci. 2002
Apr;959:128-32. [10] Breitbart E, Effects of water-soluble antioxidant from
spinach, NAO, on doxorubicin-induced heart injury. Hum Exp Toxicol. 2001
Jul;20(7):337-45. SOURCE FOR PREPARATIONS AND OTHER SECTIONS: Spinach
A 5 Day Food CDC August 2006.
Spinach is believed to be of Persian origin and introduced into
Europe in the 15th century. Since the early 19th century,
spinach has been a versatile and commonly used vegetable in
the United States. Spinach is so popular because of its taste,
nutritional value and potential health benefits. It contains low
calories, potassium, sodium, protein, iron, calcium, fibers,
vitamins A and C.
POTENTIAL HEALTH BENEFITS OF SPINACH
Spinach leaves, containing several active components, including
flavonoids, exhibit antioxidative, antiproliferative, and
antiinflammatory properties in biological systems. Spinach
extracts have been demonstrated to exert numerous beneficial
effects, such as chemo- and central nervous system protection
and anticancer and anti-aging functions.
Extracts of spinach leaves show high anti-oxidative activities
and are well tolerated in animal studies. No side effects are
reported in these animal studies. [1]
Spinach may have benefits of cutting cancer risks.
Japanese researchers proposed to use spinach extracts as
anticancer agent. They found that spinach contained a large
amount of sulfoquinovosyl diacylglycerol and this compound is a
potent inhibitor for certain human cancer cell proliferations. Of
the six subspecies of spinach (Spinacia oleracea) tested, "Anna"
had the largest amount of sulfoquinovosyl diacylglycerol,
strongest inhibitory activity toward DNA polymerase and
greatest effect on human cancer cell proliferation. Other plants
containing this compound include parsley, green onion, chive,
sweet pepper, green tea, carrot and garlic. [2]
Longnecker MP et al from National Institute of Environmental
Health Sciences observed the association between intake of
fruits, vegetables (such as carrots, spinach), vitamin A and
lower risk of breast cancer in some studies. [3]
Spinach may have benefits in neurodegenerative diseases.
Researchers from United States Department of Agriculture
reported six-month-supplementation of spinach (6.4 g/kg DEA)
was linked to significant retardation of age-effects on
neurodegenerative diseases in a study of 344 rats. [4]
Researchers from National Institute on Drug Abuse have shown
that treatment with diets enriched with blueberry, spinach, or
spirulina reduced neurodegenerative changes in aged animals.
They further demonstrated that chronic treatment with
blueberry, spinach, or spirulina reduces
ischemia/reperfusion-induced apoptosis and cerebral infarction
in a study of Sprague-Dawley rats. [5]
Researchers from University of South Florida reported 6 weeks
of a spinach-enriched diet ameliorated deficits in
cerebellar-dependent delay classical eyeblink learning and
reduced the proinflammatory cytokines tumor necrosis factor
alpha (TNFalpha) and TNFbeta in the cerebelli of eyeblink-trained
animals. Old animals on the spinach-enriched lab chow diet
learned delay eyeblink conditioning significantly faster than old
animals on the regular diet. [6]
Aging is associated with a decline in motor coordination and the
ability to learn new motor learning skills. This loss of function is
correlated with a decline in cerebellar beta-adrenergic receptor
function.
Researchers from University of Colorado Health Sciences Center
examined the role of oxidative stress on this system by
exposing young rats to normobaric hyperoxia. This exogenous
oxidative insult resulted in a decline in cerebellar
beta-adrenergic receptor function that resembleed what was
observed in normal aged rats. This effect of hyperoxia was
blocked by antioxidants. They also examined the effects of
nutritional supplementation of aged rats with diets high in
antioxidant capacity. They concluded that foods such as
blueberries and spinach can prevent and/or reverse age-related
declines in cerebellar noradrenergic receptor function. [7]
Bickford PC et al, Boston, explained that reactive oxygen
species are involved in the decline in function associated with
aging. Spinach diets or supplements containing antioxidants
reverse age-induced declines in beta-adrenergic receptor
function in cerebellar Purkinje neurons; benefit age-related
deficits in motor learning and memory. In addition, motor
learning is important for adaptation to changes in the
environment and is thus critical for rehabilitation following
stroke, spinal cord injury, and the onset of some
neurodegenerative diseases. [8]
In sum, increasing dietary intake of fruits and vegetables (such
as spinach) high in antioxidant activity may be an important
component of a healthy living strategy designed to maximize
neuronal and cognitive functioning into old age. [9]
Spinach may have benefits of heart protection.
We know that doxorubicin produces clinically restorative
responses in numerous human cancers, but its cardiotoxicity
has limited its usefulness. Israeli researchers evaluated the
prophylactic effect of spinach natural antioxidant on doxorubicin
-induced cardiotoxicity and oxidative stress in female Balb/c
mice. They found that pretreatment with spinach natural
antioxidant before doxorubicin administration decreased
catalase and increased superoxide dismutase activities
compared to the doxorubicin group. [10]
Eating Spinach
Eating and preparing spinach is simple and easy, since it tastes
good raw or cooked. Spinach can be found fresh, frozen, or
canned; it can be easily incorporated into many dishes. Its
versatility makes it easy to serve raw in salads or sandwiches or
as a complement to soups, meat, fish, or other vegetable
dishes.
At the supermarket, you can find spinach packaged fresh,
canned, or frozen. Fresh spinach is usually found loose or
bagged. For the best quality, select leaves that are green and
crisp, with a nice fresh fragrance. Avoid leaves that are limp,
damaged, or spotted. If you are in a rush, grab a bag of fresh,
pre-washed spinach. The ready-to-eat packaging makes it easy
to be on the go and still stay healthy.
Fresh spinach should be dried and packed loosely in a
cellophane or plastic bag and stored in the refrigerator crisper.
If stored properly, it should last 3 or 4 days.
Spinach grows in sandy soil, so wash it thoroughly to get rid of
the grainy, sandy particles. Make sure to tear off the stem.
Separate the leaves, and place them in a large bowl of water.
Gently wash leaves, and let the sand drift to the bottom of the
bowl. Remove leaves from the water, and repeat the process
with fresh water until the leaves are clean.
If spinach is to be eaten raw, dry it completely by using a salad
spinner or by blotting it with paper towels. Slightly damp
spinach can be steamed or microwaved without adding any
additional water.
Blanching Drop leaves into a large pot of boiling water. Once
the leaves slightly wilt, drain and squeeze out excess moisture.
This method is used to quick-cook spinach or to prepare it for
sautéing, braising, or stuffing, and usually takes 2 to 5
minutes.
Microwaving This method can be used instead of blanching.
Place washed, slightly wet spinach in a microwavable dish,
loosely cover, and cook until tender (4 to 7 minutes for ½
pound of spinach).
Sautéing Blanched spinach can be sautéed quickly with a
quick spray of oil. If cooked in a non-stick pan, only a spray is
needed for several cups of chopped spinach. Try adding some
garlic for flavor.
Steaming If you plan to steam the spinach, do not dry leaves
after washing. Steamed spinach makes a great side dish and
usually takes only 5 to 10 minutes.
Tips to improve iron and calcium absorption from
spinach
Preparation Iron and calcium in plant foods are not highly
absorbed by the body. Spinach contains a chemical called oxalic
acid, which binds with iron and calcium and reduces the
absorption of these minerals. To improve iron absorption,
spinach should be eaten with vitamin C-rich foods such as
orange juice, tomatoes, or citrus fruit.
THIS ARICLE IS FOR YOUR REFERENCE ONLY. CONSULT YOUR DOCTOR IF YOU
HAVE ANY QUESTIONS. ALL RIGHTS RESERVED 2006 ZHION
REFERENCE: [1] Lomnitski L, et al, Composition, efficacy, and safety of spinach
Nutr Cancer. 2003;46(2):222-31.extracts. [2] Kuriyama I, et al, Inhibitory effects
of glycolipids fraction from spinach on mammalian DNA polymerase activity and
human cancer cell proliferation. J Nutr Biochem. 2005 Oct;16(10):594-601. [3]
Longnecker MP, et al, Intake of carrots, spinach, and supplements containing
vitamin A in relation to risk of breast cancer. Cancer Epidemiol Biomarkers Prev.
1997 Nov;6(11):887-92. [4] Joseph JA, et al, Long-term dietary strawberry,
spinach, or vitamin E supplementation retards the onset of age-related neuronal
signal-transduction and cognitive behavioral deficits. J Neurosci. 1998 Oct
1;18(19):8047-55. [5] Wang Y, et al, Dietary supplementation with blueberries,
spinach, or spirulina reduces ischemic brain damage. Exp Neurol. 2005
May;193(1):75-84. [6] Cartford MC, et al, Eighteen-month-old Fischer 344 rats
fed a spinach-enriched diet show improved delay classical eyeblink conditioning
and reduced expression of tumor necrosis factor alpha (TNFalpha ) and TNFbeta
in the cerebellum. J Neurosci. 2002 Jul 15;22(14):5813-6. [7] Bickford PC, et al,
Effects of aging on cerebellar noradrenergic function and motor learning:
nutritional interventions. Mech Ageing Dev. 1999 Nov;111(2-3):141-54. [8]
Bickford PC, et al, Antioxidant-rich diets improve cerebellar physiology and motor
learning in aged rats. Brain Res. 2000 Jun 2;866(1-2):211-7. [9] Galli RL, et al,
Fruit polyphenolics and brain aging: nutritional interventions targeting
age-related neuronal and behavioral deficits. Ann N Y Acad Sci. 2002
Apr;959:128-32. [10] Breitbart E, Effects of water-soluble antioxidant from
spinach, NAO, on doxorubicin-induced heart injury. Hum Exp Toxicol. 2001
Jul;20(7):337-45. SOURCE FOR PREPARATIONS AND OTHER SECTIONS: Spinach
A 5 Day Food CDC August 2006.