Spinach is among the most nutrient-rich vegetables, packing a large amount of nutrients per serving for relatively few calories.
While spinach won’t give you big biceps like the cartoon Popeye might suggest, it may provide some health benefits. For example, scientific research suggests it may help improve some markers of heart health.
Spinach also provides notable levels of fiber, copper, folate, manganese, and vitamins A, C, and K, so it can make a significant contribution to nutrient sufficiency.
In this article, we examine the research on spinach, presenting its potential benefits and downsides, as well as its complete nutritional profile.
Spinach contains high levels of provitamin A carotenoids, with a 180g cup of cooked spinach providing 943 mcg of retinol activity equivalents (RAE) of vitamin A. This is equal to 105% of the Daily Value for vitamin A.
Vitamin A has many important functions in the body, but it is particularly vital for maintaining normal vision, and vitamin A deficiencies can adversely affect eyesight.
Lutein and zeaxanthin are two of the carotenoids found in high concentrations in spinach at 20,300 mcg per cup.
A systematic review and meta-analysis found that these carotenoids can increase a key marker of eye health called macular pigment optical density (MPOD). These effects were stronger in studies with a ≥20 mg (20,000 mcg) dose of lutein and zeaxanthin for 3–12 months.
There is also evidence showing that spinach intake raises blood levels of these important carotenoids. While it only had a small participant size, a study involving 12 healthy participants found that consuming a daily spinach preparation for 10 days led to a significant increase in blood levels of lutein.
Based on this research, spinach is likely a good dietary addition for helping to support healthy eyesight. In fact, a 2023 systematic review included spinach on its “ideal food pyramid” to prevent or support the management of several eye diseases.
May Help Support Heart Health
Spinach contains several nutrients and compounds that may help support cardiovascular health:
Nitrate: Spinach is a rich dietary source of inorganic nitrate, which can help increase nitric oxide production and, according to a systematic review, may help to lower blood pressure.
There has also been some research specific to spinach and its impact on markers of heart health:
FMD and blood pressure: A randomized controlled trial involving 30 healthy adults found that spinach intake improved flow-mediated dilation (FMD), and lowered pulse and systolic blood pressure. FMD is a measure of how well the arteries can dilate to manage increased blood flow.
Inorganic nitrate consumption: A systematic review found that inorganic nitrate consumption from foods including beetroot and spinach improved markers of heart health including blood pressure, arterial stiffness, and FMD.
Blood nitrate levels and blood pressure: A randomized crossover trial involving 18 participants found that a beverage made from spinach increased blood levels of nitrate. Systolic blood pressure also declined 300 minutes after consuming the beverage, with diastolic blood pressure falling 150 minutes after.
Arterial stiffness and blood pressure: Compared to a low-nitrate control meal, a high-nitrate meal containing spinach improved large artery elasticity and blood pressure in a randomized crossover trial with 26 participants. Stiffer arteries are less elastic, which can impair their ability to deal with changes in blood flow.
Research on Spinach Extract
While the evidence listed in the article thus far has focused on whole-food spinach intake, there has also been some scientific research using spinach extracts.
As these are highly concentrated extracts of compounds found within spinach, we can’t imply simply eating spinach would have the same effects.
However, there is a relevant study worth mentioning which focused on spinach extract’s impact on physical performance:
Study type: A systematic review of randomized controlled trials published in 2025.
Mechanism: The authors noted that these improvements may be due to greater nitric oxide availability, which likely resulted from the inorganic nitrate content of the spinach extract. Nitric oxide can help improve blood flow and oxygenation in the body, which can improve exercise performance.
As spinach is considered to be a rich dietary source of nitrate, it is feasible that high dietary intakes could potentially have benefits for physical performance. However, this would need confirming by further research as this study used an extract.
Potential Downsides
Can Taste Bitter
Spinach is among the strongest-tasting, most flavorful leafy green vegetables, but it has a slightly bitter taste, which not everyone enjoys. Cooked spinach tends to be milder than raw spinach, particularly if sauteed with oil and seasonings.
One of the contributors to this bitter taste is a compound in spinach called oxalic acid, which is also known as oxalate. We will look at oxalate separately as another potential downside.
If you don’t personally enjoy spinach, that isn’t an issue, and there are plenty of other, milder-tasting leafy greens that provide many nutrients.
Most things in nutrition are neither black nor white. Just as spinach has many benefits, there are some potential drawbacks to consider too.
The main one of these is oxalate (oxalic acid), an organic acid that spinach contains in high amounts. In fact, research demonstrates that spinach is one of the most concentrated dietary oxalate sources.
This can be a problem because some people are prone to developing calcium-oxalate crystals, which can lead to kidney stones. For these people, healthcare providers sometimes prescribe low-oxalate diets to minimize the risk of developing kidney stones.
Based on its high oxalate content, spinach is not a good fit for individuals following a low-oxalate diet. If you are on such a diet and still want to get some of the benefits of leafy greens, kale is a low-oxalate vegetable worth looking into.
However, for individuals with a low risk of kidney stones, spinach is a nutrient-rich vegetable that fits well into a healthy dietary pattern.
Complete Nutrition Facts
For your reference, we’ll now go through the full nutritional profile for spinach so that you can learn every nutrient it contains.
The tables below show the nutritional values of cooked spinach per 100g and per 180g cup serving. All nutritional data is sourced from the USDA’s FoodData Central database. We have calculated Percent Daily Values and rounded them to the nearest percentage.
Calories and Macronutrients
Nutrient
Per 100g (% DV)
Per 180g cup (% DV)
Calories
23 kcal
41 kcal
Carbohydrates
3.75g (1%)
6.75g (2%)
Fiber
2.4g (9%)
4.32g (15%)
Sugar
0.43g
0.77g
Fat
0.26g (<1%)
0.47g (1%)
Saturated fat
0.04g (<1%)
0.08g (<1%)
Monounsaturated fat
<0.01g
0.01g
Polyunsaturated fat
0.11g
0.20g
Omega-3
0.09g
0.17g
Omega-6
0.02g
0.03g
Cholesterol
0 mg (0%)
0 mg (0%)
Protein
2.97g (6%)
5.35g (11%)
Table 1: Calorie and macronutrient content of cooked spinach per 100g and 180g cup
Vitamins
Vitamin
Per 100g (% DV)
Per 180g cup (% DV)
Vitamin A (RAE)
524 mcg (58%)
943 mcg (105%)
Vitamin C
9.8 mg (11%)
17.6 mg (20%)
Vitamin D
0 mcg (0%)
0 mcg (0%)
Vitamin E
2.08 mg (14%)
3.74 mg (25%)
Vitamin K
494 mcg (412%)
889 mcg (741%)
Thiamin (B1)
0.10 mg (8%)
0.17 mg (14%)
Riboflavin (B2)
0.24 mg (18%)
0.43 mg (33%)
Niacin (B3)
0.49 mg (3%)
0.88 mg (6%)
Pantothenic acid (B5)
0.15 mg (3%)
0.26 mg (5%)
Vitamin B6
0.24 mg (14%)
0.44 mg (26%)
Folate (B9)
146 mcg (37%)
263 mcg (66%)
Vitamin B12
0 mcg (0%)
0 mcg (0%)
Choline
19.7 mg (6%)
35.5 mg (6%)
Table 2: Vitamin content of cooked spinach per 100g and 180g cup
Minerals
Mineral
Per 100g (% DV)
Per 180g cup (% DV)
Calcium
136 mg (10%)
245 mg (19%)
Iron
3.57 mg (20%)
6.43 mg (36%)
Magnesium
87 mg (21%)
157 mg (37%)
Phosphorus
56 mg (4%)
101 mg (8%)
Potassium
466 mg (10%)
839 mg (18%)
Sodium
70 mg (3%)
126 mg (5%)
Zinc
0.76 mg (7%)
1.37 mg (12%)
Copper
0.17 mg (19%)
0.31 mg (34%)
Manganese
0.94 mg (41%)
1.68 mg (73%)
Selenium
1.5 mcg (3%)
2.7 mcg (5%)
Table 3: Mineral content of spinach per 100g and 180g cup
Note: Why Spinach Isn’t a Good Source of Calcium
Looking at the above table, you could be forgiven for thinking spinach is a good source of calcium, with a cup providing 245 mg. However, spinach is actually considered to be a poor source of calcium.
Let me explain: The reason that spinach is a poor calcium source is because the oxalate it contains binds to calcium, making it difficult for the body to absorb it. One human study measured the absorption rate of calcium from spinach, finding that only 5.1% was absorbed.
If you are looking for calcium from vegetables, kale is a better choice considering its low oxalate content.
Summary
Overall, spinach is a nutrient-rich vegetable with particularly notable levels of vitamins A and K.
The only real cause for concern would be its oxalate content for people who are prone to developing kidney stones. However, this shouldn’t cause any fear of spinach, and it is something that most healthy individuals don’t need to worry about.
Due to this leafy green’s impressive nutrient density, it can help contribute to nutrient sufficiency for several key vitamins and minerals.
Michael works as a nutritionist in a community setting and holds a Master's degree in Clinical Nutrition. He is a Registered Associate Nutritionist (ANutr) with the Association for Nutrition (AfN), and has published peer-reviewed research.
