5 Compounds in Spinach that Elevate It to Superfood Status

April 24, 2022

by Cathe Friedrich

When you think of spinach, you probably think of Popeye the sailor man — and with good reason. If anyone branded spinach as a superfood, this cartoon character did. It gave him superpowers! But spinach isn’t just for Popeye, it’s for everyone who wants to look and feel their best. Spinach is a cornerstone of many healthy diets and is versatile enough to enjoy in a variety of ways – sauteed, raw, or steamed. Spinach is a nutritional superstar. It contains various vitamins and minerals, but these compounds make it an even more worthwhile addition to your plate.

Ecdysterone

When you think of building muscle and preventing muscle loss, protein-rich, animal-based foods likely come to mind. But maybe you should also think of spinach. Scientists have uncovered that a plant compound called Epidysterone, a type of phytosteroid, in spinach helps protect against muscle loss. Ecdysterone is found in spinach and other leafy greens and has a similar structure to cholesterol.

What makes this compound so intriguing? Research shows ecdysterone may prevent muscle loss and boost protein synthesis in skeletal muscle. It’s no surprise that bodybuilding supplements contain this compound, but now you know where it comes from – spinach. Plus, bodybuilding supplements are highly processed while spinach is a whole food.

Beta-Carotene

Beta-carotene is an antioxidant and anti-inflammatory nutrient that belongs to a class of compounds called carotenoids. You probably know that carrots and other orange vegetables are a good source of beta-carotene, but did you know that vegetables like spinach, kale, and broccoli are loaded with beta-carotene too? Don’t let the lack of orange fool you. The chlorophyll in spinach masks the orange color of beta-carotene in leafy greens but they’re still jam-packed with this anti-inflammatory nutrient.

Beta carotene is a compound that the body converts into vitamin A. Vitamin A is essential for healthy eyes and skin, as well as helping control your immune system and preserve skin and eye health. But beta carotene also has antioxidant and anti-inflammatory activity independent of its conversion to vitamin A. You can boost the amount of beta-carotene your body absorbs from spinach and other beta-carotene rich foods by eating them with a source of fat, like olive oil. You won’t absorb a significant amount of beta-carotene if you consume it with a fat-free meal.

Lutein

Spinach is also rich in a compound called lutein that helps protect the light-sensitive retina in the back of your eye against damage. Some studies show this protection may lower the risk of age-related macular degeneration, the most common cause of visual impairment in older adults. Spinach also contains zeaxanthin, another antioxidant that can help protect against macular degeneration, although spinach contains less zeaxanthin than lutein.

To cook or not to cook? To maximize lutein, give your spinach a saute. Cooking increases the amount of lutein in spinach. Other dark, leafy green vegetables contain substantial quantities of lutein and zeaxanthin, including Swiss chard, mustard greens, turnip greens, collard greens, and kale. You’ll get higher concentrations of lutein if you cook leafy greens before eating them. However, you will lose more of their vitamin C. So, eat both!

Vitamin K

Spinach is rich in vitamin K, an important nutrient your body needs to help your blood clot when you’re injured. It is also essential for synthesizing certain proteins, which are necessary for maintaining strong bones and healthy arteries.

Vitamin K has several forms, but vitamin K1 and K2 are the most common. Vitamin K1 supports blood clotting while vitamin K2 is more important for bone health. Some studies suggest that a diet rich in vitamin K2 may lower the risk of osteoporosis and cardiovascular disease.

Although spinach contains mostly vitamin K1, your body can convert some vitamin K1 to vitamin K2. Spinach contains an unusually high amount of vitamin K per serving, with only one cup providing 177 percent of your daily value.

Nitrates

Spinach is also an abundant source of nitrates, compounds your blood vessels convert to nitric oxide. When nitrates in spinach, beetroot and celery convert to nitric oxide, inside your blood vessels, it lowers blood pressure. Plus, it improves blood vessel function in a way that reduces the risk of blood clots forming. How does nitric oxide lower blood pressure? Nitric oxide helps relax the walls of arteries, so there’s less resistance to blood flow. No wonder spinach is a heart-healthy vegetable.

The Bottom Line

Do you think these benefits are enough to catapult spinach to superfood status? The potential benefits are compelling. The good news is spinach is less expensive than trendier superfoods like acai and camu- camu that come with a hefty price tag. It’s also widely available. If you eat spinach regularly cook it lightly. Doing so will reduce the number of oxalates in spinach, compounds that increase the risk of calcium oxalate kidney stones. Also, choose organic if it’s available, as spinach contains more pesticides residues than some other products. If you have a history of kidney stones, talk to your physician about whether you should eat spinach.

References:

Lomnitski L, Bergman M, Nyska A, Ben-Shaul V, Grossman S. Composition, efficacy, and safety of spinach extracts. Nutr Cancer. 2003;46(2):222-31. doi: 10.1207/S15327914NC4602_16. PMID: 1469079
Parr MK, Botrè F, Naß A, Hengevoss J, Diel P, Wolber G. Ecdysteroids: A novel class of anabolic agents? Biol Sport. 2015 Jun;32(2):169-73. doi: 10.5604/20831862.1144420. Epub 2015 Mar 15. PMID: 26060342; PMCID: PMC4447764.9.
Sommerburg O, Keunen JE, Bird AC, van Kuijk FJ. Fruits and vegetables that are sources for lutein and zeaxanthin: the macular pigment in human eyes. Br J Ophthalmol. 1998 Aug;82(8):907-10. doi: 10.1136/bjo.82.8.907. PMID: 9828775; PMCID: PMC1722697.
“LUTEIN: Overview, Uses, Side Effects, Precautions ….” .webmd.com/vitamins/ai/ingredientmono-754/lutein.
Lidder S, Webb AJ. Vascular effects of dietary nitrate (as found in green leafy vegetables and beetroot) via the nitrate-nitrite-nitric oxide pathway. Br J Clin Pharmacol. 2013 Mar;75(3):677-96. doi: 10.1111/j.1365-2125.2012.04420.x. PMID: 22882425; PMCID: PMC3575935.
Roberts JL, Moreau R. Functional properties of spinach (Spinacia oleracea L.) phytochemicals and bioactives. Food Funct. 2016 Aug 10;7(8):3337-53. doi: 10.1039/c6fo00051g. Epub 2016 Jun 29. PMID: 27353735.