Spinach was apparently first cultivated in ancient Persia and then spread along trading routes to India and China. Not until the ninth century was it introduced to southern Europe, and several hundred years later, to England.
It is one of the most nutritious of all vegetables, with high levels of antioxidants and vitamins A, C, E, and K, along with zinc, iron, selenium, folic acid, omega-3 fatty acids, and numerous other nutrients. Studies indicate that spinach consumption can help reduce the risk of at least nine types of cancer.
Dietary supplementation with blueberries, spinach, or spirulina reduces ischemic brain damage. Wang Y, Chang CF, Chou J, Chen HL, Deng X, Harvey BK, Cadet JL, Bickford PC. Exp Neurol. 2005 May;193(1):75-84. Key Finding: “Free radicals are involved in neurodegenerative disorders, such as ischemia and aging. We have previously demonstrated that treatment with diets enriched with blueberry, spinach, or spirulina have been shown to reduce neurodegenerative changes in aged animals. The purpose of this study was to determine if these diets have neuroprotective effects in focal ischemic brain in Sprague-Dawley rats. Animals treated with blueberry, spinach, or spirulina had significantly lower caspase-3 activity in the ischemic hemisphere. In conclusion, our data suggest that chronic treatment with blueberry, spinach, or spirulina reduces ischemia/reperfusion-induced apoptosis and cerebral infarction.”
Oxidative stress protection and vulnerability in aging: putative nutritional implications for intervention. Joseph JA, Denisova NA, Bielinski D, Fisher DR, Shukitt-Hale B. Mech Ageing Dev. 2000 Jul 31;116(2-3):141-53. Key Finding: “Among the most effective agents that antagonized cellular oxidative stress were the combination of polyphenols found in fruits (e.g. blueberry extract) with high antioxidant activity. Subsequent experiments using dietary supplementation with fruit (strawberry) or vegetable (spinach) extracts have shown that such extracts are also effective in forestalling and reversing the deleterious effects of behavioral aging in F344 rats.”
Reversals of age-related declines in neuronal signal transduction, cognitive, and motor behavioral deficits with blueberry, spinach, or strawberry dietary supplementation. Joseph JA, Shukitt-Hale B, Denisvoa NA, Bielinski D, Martin A, McEwen JJ, Bickford PC. J Neurosci. 1999 Sep 15;19(18):8114-21. Key Finding: “Our previous study had shown that rats given dietary supplements of fruits and vegetable extracts with high antioxidant activity for 8 months beginning at 6 months of age retarded age-related declines in neuronal and cognitive function. The present study showed that such supplements (strawberry, spinach or blueberry) fed for 8 weeks to 19-month-old Fischer 344 rats were also effective in reversing age-related deficits in several neuronal and behavioral parameters. These findings suggest that, in addition to their known beneficial effects on cancer and heart disease, phytochemicals present in antioxidant-rich foods may be beneficial in reversing the course of neuronal and behavioral aging.”
Membrane and receptor modifications of oxidative stress vulnerability in aging. Nutritional considerations. Joseph JA, Denisova N, Fisher D, Shukitt-Hale B, Bickford P, Prior R, Cao G. Ann N Y Acad Sci. 1998 Nov 20;854:268-76. Key Finding: “Evidence suggests that oxidative stress may contribute to the pathogenesis of age-related decrements in neuronal function and that OS vulnerability increases as a function of age. In studies attempts have been made to determine whether increased OS protection via nutritional increases in antioxidant levels in rats (strawberry extracts, dried aqueous extract, spinach, or blueberry extracts) would protect against exposure to 100% O2 (a model of accelerated neuronal aging.) Results indicated that these diets were effective in preventing OS-induced decrements in several parameters, suggesting that although there maybe increases in OS vulnerability in aging, phytochemicals present in antioxidant-rich foods may be beneficial in reducing or retarding the functional central nervous system deficits seen in aging or oxidative insult.”
Antioxidant and antiproliferative activities of common vegetables. Chu YF, Sun J, WuX, Liu RH. J Agric Food Chem. 2002 Nov 6;50(23):6910-6. Key Finding: “In this study, 10 common vegetables were selected on the basis of consumption per capita data in the U.S. Broccoli possessed the highest total phenolic content, followed by spinach, yellow onion, red pepper, carrot, cabbage, potato, lettuce, celery, and cucumber. Red pepper had the highest total antioxidant activity, followed by broccoli, carrot, spinach, cabbage, yellow onion, celery, potato, lettuce and cucumber. Antiproliferative activities were also studied in vitro using human liver cancer cells. Spinach showed the highest inhibitory effect, followed by cabbage, red pepper, onion, and broccoli.”
Serum antioxidant capacity is increased by consumption of strawberries, spinach, red wine or vitamin C in elderly women. Cao G, Russell RM, Lischner N, Prior RL. J Nutr. 1998 Dec;128(12):2383-90. Key Finding: “In this study we investigated the responses in serum total antioxidant capacity following consumption of strawberries (240 g), spinach (294 g), red wine (300 ml) or vitamin C (1250 mg) in eight elderly women. The results showed that the total antioxidant capacity of serum determined as ORAC, TEAC and FRAP, using the area under the curve, increased significantly by 7-25% during the 4-h period following consumption. The total antioxidant capacity of urine determined by ORAC increased (P<0.05) by 9.6, 27.5 and 44.9% for strawberries, spinach, and vitamin C respectively during the 24-h period following these treatments.”
Phytoestrogens and human health effects: weighing up the current evidence. Humfrey CD. Nat Toxins. 1998;6(2):51-9. Key Finding: “Phytoestrogens are present in beans, sprouts, cabbage, spinach, soybean, grains and hops. Epidemiological studies suggest that foodstuffs containing phytoestrogens may have a beneficial role in protecting against a number of chronic diseases and conditions. For cancer of the prostate, colon, rectum, stomach and lung, the evidence is most consistent for a protective effect. Soya and linseed may have beneficial effects on the risk of breast cancer and may help to alleviate postmenopausal symptoms. Soya also appears to have beneficial effects on blood lipids which may help to reduce the risk of cardiovascular disease and atherosclerosis.”
Phytochemicals that counteract the cardio toxic side effects of cancer chemotherapy. Piasek A, Bartoszek A, Namiesnik J. Postepy Hig Med Dosw (Polish). 2009 Apr 17;63:142-58. Key Finding: “Dietary intervention with antioxidants (such as in tomato, garlic, spinach) may be a safe and effective way of alleviating the toxicity of anticancer chemotherapy and preventing heart failure.”
Identifying efficacious approaches to chemoprevention with chlorophyllin purified chlorophylls and freeze-dried spinach in a mouse model of transplacental carcinogenesis. Castro DJ, Lohr CV, Fischer KA, Waters KM, Webb-Robertson BJ, Dashwood RH, Bailey GS, Williams DE. Carcinogenesis. 2009 Feb;30(2):315-20. Key Finding: “Coadministration of chlorophyllin provided significant protection against DBP-initiated carcinogenesis. Coadministration of CHL also reduced lung tumor multiplicity in mice by approximately 50%.”
Anti-tumor effect of orally administered spinach glycolipid fraction on implanted cancer cells, colon-26, in mice. Maeda N, Kokai Y, Ohtani S, Sahara H, Et al. Lipids. 2008 Aug;43(8):741-8. Key Finding: “These results suggest that the orally administered glycolipid fraction from spinach could suppress colon tumor growth in mice by inhibiting the activities of neovascularization and cancer cellular proliferation in tumor tissue.”
Inhibitory effect on replicative DNA polymerases, human cancer cell proliferation, and in vivo anti-tumor activity by glycolipids from spinach. Maeda N, Hada T, Yoshida H, Mizushina Y. Curr Med Chem. 2007;14(9):955-67. Key Finding: “The spinach Fraction-II containing SQDG might be a potent anti-tumor compound and may be a healthy food substance with anti-tumor activity.”
Prospective study of fruit and vegetable intake and risk of prostate cancer. Kirsh VA, Peters U, Mayne ST, Subar AF, Et al. J Natl Cancer Inst. 2007 Aug 1;99(15):1200-9. Key Finding: “High intake of broccoli, cauliflower, may be associated with reduced risk of aggressive prostate cancer. We found some evidence that risk of aggressive prostate cancer decreased with increasing spinach consumption.”
Differential attenuation of oxidative/nitrosative injuries in early prostatic neoplastic lesions in TRAMP mice by dietary antioxidants. Tam NN, Nyska A, Maronpot RR, Kissling G, Lomnitski L, Et al. Prostate. 2006 Jan 1;66(1):57-69. Key Finding: “Our data indicate that in TRAMP mice, OS/NS injuries are likely involved in early prostatic tumorigenesis and can be modulated by various antioxidants such as from spinach extracts.”
Correlates between vegetable consumption and gallbladder cancer. Rai A, Mohapatra SC, Shukla HS. Eur J Cancer Prev. 2006 Apr;15(2):134-7. Key Finding: “A significant inverse trend was observed for green leafy vegetables and gallbladder cancer. An inverse association was observed for spinach, cabbage and fenugreek leaves.”
Green vegetables, red meat and colon cancer: chlorophyll prevents the cytotoxic and hyper proliferative effects of haem in rat colon. De Vogel J, Jonker-Termont DS, Van Lieshout EM, Katan MB, Van der Meer R. Carcinogenesis. 2005 Feb;26(2):387-93. Key Finding: “We studied whether green vegetables inhibit the unfavorable colonic effects of haem from red meat. Spinach or an equimolar amount of chlorophyll supplement in the haem diet in rats inhibited the haem effect completely. Haem clearly inhibited exfoliation of colonocytes, an effect counteracted by spinach and chlorophyll.”
Inhibitory effect of glycolipids from spinach on in vitro and ex vivo angiogenesis. Matsubara K, Matsumoto H, Mizushina Y, Mori M, Naksjima N, Et al. Oncol Rep. 2005 Jul;14(1):157-60. Key Finding: “These results demonstrate that glycolipids from spinach would suppress tumor growth by suppressing angiogenesis and might be candidates for anti-cancer or anti-angiogenic materials.”
Effects of DNA polymerase inhibitory and antitumor activities of lipase-hydrolyzed glycolipid fractions from spinach. Maeda N, Hada T, Murakami-Nakai C, Kuriyama I, Ichikawa H, Fukumori Y, Et al. J Nutr Biochem. 2005 Feb;16(2):121-8. Key Finding: “Spinach glycolipid fraction might be a potent antitumor compound. This glycolipid fraction was an inhibitor of DNA polymerases and a growth inhibitor of NUGC-3 human gastric cancer cells.”
Inhibitory effects of glycolipids fraction from spinach on mammalian DNA polymerase activity and human cancer cell proliferation. Kuriyama I, Musumi K, Yonezawa Y, Takemura M, Maeda N, Et al. J Nutr Biochem. 2005 Oct;16(10):594-601. Key Finding: “Of the six subspecies of spinach tested, “Anna” had the largest amount of SQDG, strongest inhibitory activity toward DNA polymerase and greatest effect on human cancer cell proliferation. Based on these results, the glycolipids fraction from spinach is potentially a source of food material for a novel anticancer activity.”
Retinoic acid and retinoid receptors: potential chemo preventive and therapeutic role in cervical cancer. Abu J, Batuwangala M, Herbert K, Symonds P. Lancet Oncol. 2005 Sep;6(9):712-20. Key Finding: “Retinoids are derivatives of vitamin A which can be obtained from spinach, carrots, sweet potatoes, mangos and others. Retinoids regulate various important cellular functions in the body through specific nuclear retinoic-acid receptors and retinoid-X receptors, which are encoded by separate genes. Several experimental and epidemiological studies have shown the antiproliferative activity of retinoids and their potential use in cancer treatment and chemoprevention. Emerging clinical trials have shown the chemotherapeutic and chemo preventive potential of retinoids in cancerous and precancerous conditions of the uterine cervix.”
Unique natural antioxidants (NAOs) and derived purified components inhibit cell cycle progression by down regulation of ppRb and E2F in human PC3 prostate cancer cells. Bakshi S, Bergman M, Dovrat S, Grossman S. FEBS Lett. 2004 Aug 27;573(1-3):31-7. Key Finding: “In the present study, we explored the signaling mechanism through which unique natural antioxidant derived from spinach extract exerts their beneficial effects in the chemoprevention of prostate cancer using human PC3 cells.”
Potential anticancer effect of red spinach (Amaranthus gangeticus) extract. Sani HA, Rahmat A, Ismail M, Rosli R, Endrini S. Asia Pac J Clin Nutr. 2004;13(4):396-400. Key Finding: “A. gangeticus inhibited the proliferation of liver cancer cell line HepG2 and breast cancer cell line MCF-7 and colon cancer cell line Caco-2.”
Slowing tumorigenic progression in TRAMP mice and prostatic carcinoma cell lines using natural antioxidant from spinach, NAO-a comparative study of three antioxidants. Nyska A, Suttie A, Bakshi S, Et al. Toxicol Pathol. 2003 Jan-Feb;31(1):39-51. Key Finding: “The anti-oxidative and antiproliferative properties of NAO from spinach leaves may explain its efficacy in slowing the spontaneous prostatic carcinogenic progress in the TRAMP model and its effects in the cell lines.”
Antioxidant and antiproliferative activities of common vegetables. Chu YF, Sun J, WuX, Liu RH. J Agric Food Chem. 2002 Nov 6;50(23):6910-6. Key Finding: “In this study, 10 common vegetables were selected on the basis of consumption per capita data in the U.S. Broccoli possessed the highest total phenolic content, followed by spinach, yellow onion, red pepper, carrot, cabbage, potato, lettuce, celery, and cucumber. Red pepper had the highest total antioxidant activity, followed by broccoli, carrot, spinach, cabbage, yellow onion, celery, potato, lettuce and cucumber. Antiproliferative activities were also studied in vitro using human liver cancer cells. Spinach showed the highest inhibitory effect, followed by cabbage, red pepper, onion, and broccoli.”
Carotenoids affect proliferation of human prostate cancer cells. Kotake-Nara E, Kushiro M, Zhang H, Sugawara T, Miyashita K, Nagao A. Nutrition. 2001 Dec;131(12):3303-6. Key Finding: “When the prostate cancer cells were cultured in a carotenoid-supplemented medium for 72 h at 20 micromol/L,5,6-monoepoxy carotenoids, namely, neoxanthin from spinach and fucoxanthin from brown algae, significantly reduced cell viability.”
Carotenoids and colon cancer. Slattery ML, Benson J, Curtin K, Ma KN, Schaeffer D, Potter JD. Am J Clin Nutr. 2000 Feb;71(2):575-82. Key Finding: “Lutein was inversely associated with colon cancer in both men and women studied. The major dietary sources of lutein in subjects with colon cancer and in control subjects were spinach, broccoli, lettuce, tomatoes, oranges and orange juice, carrots, celery, and greens. These data suggest that incorporating these foods into the diet may help reduce the risk of developing colon cancer.”
Effects of spinach powder fat-soluble extract on proliferation of human gastric adenocarcinoma cells. He T, Huang CY, Chen H, Hou YH. Biomed Environ Scit. 1999 Dec;12(4):247-52. Key Finding: “The results indicated that extract of spinach powder inhibited the proliferation and colony forming ability of SGC-7901 cells. And in MTT assay, it inhibited the viability of SGC-7901 cells, but no inhibitory effect was observed on the viability of lymphocytes in peripheral blood of healthy people.”
Phytoestrogens and human health effects: weighing up the current evidence. Humfrey CD. Nat Toxins. 1998;6(2):51-9. Key Finding: “Phytoestrogens are present in beans, sprouts, cabbage, spinach, soybean, grains and hops. Epidemiological studies suggest that foodstuffs containing phytoestrogens may have a beneficial role in protecting against a number of chronic diseases and conditions. For cancer of the prostate, colon, rectum, stomach and lung, the evidence is most consistent for a protective effect. Soya and linseed may have beneficial effects on the risk of breast cancer and may help to alleviate postmenopausal symptoms. Soya also appears to have beneficial effects on blood lipids which may help to reduce the risk of cardiovascular disease and atherosclerosis.”
Phytoestrogens and human health effects: weighing up the current evidence. Humfrey CD. Nat Toxins. 1998;6(2):51-9. Key Finding: “Phytoestrogens are present in beans, sprouts, cabbage, spinach, soybean, grains and hops. Epidemiological studies suggest that foodstuffs containing phytoestrogens may have a beneficial role in protecting against a number of chronic diseases and conditions. For cancer of the prostate, colon, rectum, stomach and lung, the evidence is most consistent for a protective effect. Soya and linseed may have beneficial effects on the risk of breast cancer and may help to alleviate postmenopausal symptoms. Soya also appears to have beneficial effects on blood lipids which may help to reduce the risk of cardiovascular disease and atherosclerosis.”
Effect of fruits, vegetables, or vitamin E-rich diet on vitamins E and C distribution in peripheral and brain tissues: implications for brain function. Martin A, Prior R, Shukitt-Hale B, Cao G, Joseph JA. J Gerontol A Biol Sci Med Sci. 2000 Mar;55(3):B144-51. Key Finding: “Compared to the control group, rats supplemented with strawberry, spinach or vitamin E showed a significant enhancement in striatal dopamine release. These findings suggest that other nutrients present in fruits and vegetables, in addition to the well-known antioxidants, may be important for brain function.”
Reversals of age-related declines in neuronal signal transduction, cognitive, and motor behavioral deficits with blueberry, spinach, or strawberry dietary supplementation. Joseph JA, Shukitt-Hale B, Denisvoa NA, Bielinski D, Martin A, McEwen JJ, Bickford PC. J Neurosci. 1999 Sep 15;19(18):8114-21. Key Finding: “Our previous study had shown that rats given dietary supplements of fruits and vegetable extracts with high antioxidant activity for 8 months beginning at 6 months of age retarded age-related declines in neuronal and cognitive function. The present study showed that such supplements (strawberry, spinach or blueberry) fed for 8 weeks to 19-month-old Fischer 344 rats were also effective in reversing age-related deficits in several neuronal and behavioral parameters. These findings suggest that, in addition to their known beneficial effects on cancer and heart disease, phytochemicals present in antioxidant-rich foods may be beneficial in reversing the course of neuronal and behavioral aging.”
Long-term dietary strawberry, spinach, or vitamin E supplementation retards the onset of age-related neuronal signal-transduction and cognitive behavioral deficits. Joseph JA, Shukitt-Hale B, Denisova NA, Prior RL, Cao G, Martin A, Taglialatela G, Bickford PC. J Neurosci. 1998 Oct 1;18(19):8047-55. Key Finding: “Phytochemicals present in antioxidant-rich foods such as spinach may be beneficial in retarding functional age-related CNS and cognitive behavioral deficits and, perhaps, may have some benefit in neurodegenerative disease.”
Membrane and receptor modifications of oxidative stress vulnerability in aging. Nutritional considerations. Joseph JA, Denisova N, Fisher D, Shukitt-Hale B, Bickford P, Prior R, Cao G. Ann N Y Acad Sci. 1998 Nov 20;854:268-76. Key Finding: “Evidence suggests that oxidative stress may contribute to the pathogenesis of age-related decrements in neuronal function and that OS vulnerability increases as a function of age. In studies attempts have been made to determine whether increased OS protection via nutritional increases in antioxidant levels in rats (strawberry extracts, dried aqueous extract, spinach, or blueberry extracts) would protect against exposure to 100% O2 (a model of accelerated neuronal aging.) Results indicated that these diets were effective in preventing OS-induced decrements in several parameters, suggesting that although there maybe increases in OS vulnerability in aging, phytochemicals present in antioxidant-rich foods may be beneficial in reducing or retarding the functional central nervous system deficits seen in aging or oxidative insult.”
Dietary sources of aldose reductase inhibitors: prospects for alleviating diabetic complications. Sarawat M, Muthenna P, Suryanarayana P, Petrash JM, Reddy GB. Asia Pac J Clin Nutr. 2008;17(4):558-65. Key Finding: “Among 22 dietary sources tested for aldose reductase inhibitory potential to treat secondary complications of diabetes, 10 showed considerable inhibitory potential. These include spinach, black pepper, cumin, and lemon.”
Phytoestrogens and human health effects: weighing up the current evidence. Humfrey CD. Nat Toxins. 1998;6(2):51-9. Key Finding: “Phytoestrogens are present in beans, sprouts, cabbage, spinach, soybean, grains and hops. Epidemiological studies suggest that foodstuffs containing phytoestrogens may have a beneficial role in protecting against a number of chronic diseases and conditions. For cancer of the prostate, colon, rectum, stomach and lung, the evidence is most consistent for a protective effect. Soya and linseed may have beneficial effects on the risk of breast cancer and may help to alleviate postmenopausal symptoms. Soya also appears to have beneficial effects on blood lipids which may help to reduce the risk of cardiovascular disease and atherosclerosis.”