Spinach

When your mother told you to eat your spinach, she knew what she was talking about. The deep green, leafy vegetable is full of good stuff like calcium, iron, protein, fibre and vitamin A, and is is a powerful antioxidant.

Spinach is also one of the best sources of magnesium, a vital nutrient when it comes to overall health. Research suggests that low levels of magnesium have been associated with chronic diseases, such as migraine headaches, Alzheimer’s disease, stroke, hypertension, heart disease and type 2 diabetes.

Magnesium also serves an important function when it comes to other vital vitamins and minerals: it aids in the absorption of vitamin D. This is why we’ve chosen spinach as a key ingredient in our Vitamin D Booster.

Research on spinach also suggests the vegetable may have anti-inflammatory, neuroprotective properties and anti-aging functions.

Active constituents
Flavonoids: patuletin (3,5,7,3,4-penthahydroxy-6-methoxyflavone), spinacetin, glucuronides and acylated di-and triglycosides of methylated and methylene dioxide derivatives of 6-oxygenated flavonols (4–6), magnesium, calcium, phosphorus, iron, protein, potassium, vitamin A, K, folate, fibre and chlorophyll.

AVAILABLE RESEARCH

Source of Magnesium

This review presents recent research in the areas of magnesium and chronic disease, with the goal of emphasizing magnesium's role in disease prevention and overall health. The authors suggest that low levels of magnesium have been associated with a number of chronic diseases including migraine headaches, Alzheimer's disease, cerebrovascular accident (stroke), hypertension, cardiovascular disease, and type 2 diabetes mellitus. Finally, it suggests that good food sources of magnesium include spinach.

Volpe, Stella Lucia. “Magnesium in disease prevention and overall health.” Advances in nutrition (Bethesda, Md.) vol. 4,3 378S-83S. 1 May. 2013, doi:10.3945/an.112.003483

In this study, spinach was evaluated for its bioavailability of magnesium in the experiment with magnesium-deficient rats. The effect of oxalic acid on absorption of dietary magnesium was also examined in the same experiment. The data indicates that spinach is one of the most promising sources of magnesium.

Kikunaga, S et al. “The bioavailability of magnesium in spinach and the effect of oxalic acid on magnesium utilization examined in diets of magnesium-deficient rats.” Journal of nutritional science and vitaminology vol. 41,6 (1995): 671-85. doi:10.3177/jnsv.41.671

ADDITIONAL RESEARCH

There is ongoing research on the effects of spinach as it relates to the following health concerns:

Antioxidant

The present study aimed to evaluate the antioxidant effects of spinach in vitro and in vivo in hyperlipidemic rats. The research suggests that the antioxidant activity of spinach may be an effective way to ameliorate high fat and cholesterol diet-induced oxidative stress.

Ko, Sang-Heui et al. “Antioxidant Effects of Spinach (Spinacia oleracea L.) Supplementation in Hyperlipidemic Rats.” Preventive nutrition and food science vol. 19,1 (2014): 19-26. doi:10.3746/pnf.2014.19.1.019

In this review article, the researchers present a compilation of epidemiological and preclinical data generated in their laboratories and those of other investigators describing the chemical composition of spinach, relative safety information, and its beneficial effects, including antioxidative and anti-inflammatory properties, its effects on the nervous system, as well as its anti-cancer and anti-aging functions.

Lomnitski, Liat, et al. "Composition, efficacy, and safety of spinach extracts." Nutrition and cancer 46.2 (2003): 222-231.

The present study attempted to investigate the radioprotective efficacy of spinach against radiation-induced oxidative stress in mice. The researchers believe spinach leaves are rich in antioxidants like carotenoids (beta-carotene, lutein and zeaxanthin) and high content of proteins, minerals, vitamin C. They concluded that spinach extract pretreatment renders protection against various biochemical changes in the mice testis to some extent if taken continuously, which might be due to synergistic effect of antioxidant constituents present in the spinach.

Sisodia, Rashmi et al. “Spinacia oleracea Modulates Radiation-Induced Biochemical Changes in Mice Testis.” Indian journal of pharmaceutical sciences vol. 70,3 (2008): 320-6. doi:10.4103/0250-474X.42980

Anti-Cancer

In this study, the bioactivities of purified glycoglycerolipids from spinach have been investigated extensively. The results showed that the effect of these glycoglycerolipids on cancer cells, angiogenesis and solid tumor growth might be mediated via their inhibition of replicative DNA polymerase activities. On the basis of these findings, the researchers discuss plant chloroplast glycoglycerolipids as anti-cancer therapeutic agents.

Maeda, N., et al. "Anti-cancer effect of spinach glycoglycerolipids as angiogenesis inhibitors based on the selective inhibition of DNA polymerase activity." Mini reviews in medicinal chemistry 11.1 (2011): 32-38.

In this comparative study, researchers examined the antiproliferative and antioxidant activities of 34 common vegetables including spinach, on the proliferation of 8 different tumour cell lines. It was found that spinach has a very high chemopreventive potential.

Boivin, Dominique, et al. "Antiproliferative and antioxidant activities of common vegetables: A comparative study." Food Chemistry 112.2 (2009): 374-380.

This study succeeded in purifying the fraction major glycolipids from a green vegetable, spinach (Spinacia oleraceaL), through an in vivo anti-tumor assay on mice bearing solid tumors. As a result, the data found that the spinach glycolipids fraction might be a potent anti-tumor compound, and this fraction may be a healthy food substance with anti-tumor activity.

Maeda, Naoki, et al. "Anti-tumor effects of the glycolipids fraction from spinach which inhibited DNA polymerase activity." Nutrition and cancer 57.2 (2007): 216-223.

This study assessed whether glycoglycerolipids from spinach (including MGDG) can enhance the cytotoxic effects of radiation in human pancreatic cancer cells in vitro and in vivo. The results demonstrate that MGDG enhances the ability of radiation to kill cancer cells. It also indicates that this therapeutic combination can be an effective strategy for the treatment of pancreatic cancer.

Akasaka, Hiroaki et al. “MGDG extracted from spinach enhances the cytotoxicity of radiation in pancreatic cancer cells.” Radiation oncology (London, England) vol. 11,1 153. 22 Nov. 2016, doi:10.1186/s13014-016-0729-0

Controls Appetite

The aim of this study was to investigate whether thylakoids (membrane proteins derived from spinach leaves), when added to a test meal, affect appetite regulation and blood parameters in healthy individuals. The data found that the addition of thylakoids to energy-dense food promotes satiety signals and reduces insulin response during a single meal.

Köhnke, Rickard, et al. "Thylakoids promote release of the satiety hormone cholecystokinin while reducing insulin in healthy humans." Scandinavian journal of gastroenterology 44.6 (2009): 712-719.

The purpose of this study was to investigate how treatment with a single dose of thylakoids (prepared from baby spinach leaves) before breakfast affects homeostatic as well as hedonic hunger in 32 women. The research concludes that thylakoids may be used as a food supplement to reduce homeostatic and hedonic hunger, associated with overeating and obesity.

Stenblom, Eva-Lena, et al. "Consumption of thylakoid-rich spinach extract reduces hunger, increases satiety and reduces cravings for palatable food in overweight women." Appetite 91 (2015): 209-219.

This study examined the effect of consuming a single dose of concentrated extract of thylakoids from spinach on satiety, food intake, lipids, and glucose compared to a placebo, in 60 overweight and obese individuals. The research suggests that at the dose used in this study, spinach extract containing thylakoids increases satiety over a 2-hour period compared to a placebo. In addition, thylakoid consumption may influence gender-specific food cravings.

Rebello, Candida J et al. “Acute Effects of a Spinach Extract Rich in Thylakoids on Satiety: A Randomized Controlled Crossover Trial.” Journal of the American College of Nutrition vol. 34,6 (2015): 470-7. doi:10.1080/07315724.2014.1003999

Neuroprotective Effects

The purpose of this study was to determine if diets enriched with blueberry, spinach, or spirulina have neuroprotective effects. The data suggests that chronic treatment with blueberry, spinach or spirulina reduces ischemia/reperfusion-induced apoptosis and cerebral infarction.

Wang, Yun, et al. "Dietary supplementation with blueberries, spinach, or spirulina reduces ischemic brain damage." Experimental neurology 193.1 (2005): 75-84.

The objective of this article was to conduct a review on various ethnomedicinal uses of the spinach and its influences on the pathophysiology of Alzheimer's disease based on a literature review. Based on the research found, the authors conclude that that spinach may be the anti-Alzheimer's plant.

Jiraungkoorskul, Wannee. “Review of Neuro-nutrition Used as Anti-Alzheimer Plant, Spinach, Spinacia oleracea.” Pharmacognosy reviews vol. 10,20 (2016): 105-108. doi:10.4103/0973-7847.194040

The present study sought to show how supplements (strawberry, spinach, or blueberry) fed to rats were 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.

Joseph, James A., et al. "Reversals of age-related declines in neuronal signal transduction, cognitive, and motor behavioral deficits with blueberry, spinach, or strawberry dietary supplementation." Journal of Neuroscience 19.18 (1999): 8114-8121.

Other:

This review examines the functional properties of spinach in cell culture, animals and humans with a focus on the molecular mechanisms by which spinach-derived, non-essential phytochemicals and bioactives, such as glycolipids and thylakoids, impart their health benefits.

Roberts, Joseph L., and Régis Moreau. "Functional properties of spinach (Spinacia oleracea L.) phytochemicals and bioactives." Food & function 7.8 (2016): 3337-3353.

This study aims to investigate the omega-3 and omega-6 content of food groups including vegetables, fruits, dry goods, high protein products, dairies, breads, and spices, prescribed or prohibited by Iranian Traditional Medicine (ITM). The study showed that spinach can be considered as medicinal foods for depressed patients.

Tavakkoli-Kakhki, Mandana et al. “Omega-3 and omega-6 content of medicinal foods for depressed patients: implications from the Iranian Traditional Medicine.” Avicenna journal of phytomedicine vol. 4,4 (2014): 225-30.

The objective of this study was to investigate the independent and additive effects of flavonoid-rich apples and nitrate-rich spinach on nitric oxide status, endothelial function, and blood pressure through a randomized, controlled, crossover trial with healthy men and women. The results found that flavonoid-rich apples and nitrate-rich spinach can independently augment nitric oxide status, enhance endothelial function, and lower blood pressure acutely, outcomes that may benefit cardiovascular health.

Bondonno, Catherine P., et al. "Flavonoid-rich apples and nitrate-rich spinach augment nitric oxide status and improve endothelial function in healthy men and women: a randomized controlled trial." Free Radical Biology and Medicine 52.1 (2012): 95-102.