Spinach is packed with vitamins K, A, C, and several B vitamins, along with meaningful amounts of iron, calcium, magnesium, and potassium. A single cup of raw spinach delivers nearly twice the daily recommended intake of vitamin K alone. Here’s a closer look at what’s inside and how your body actually uses it.
Vitamin K: The Standout Nutrient
Vitamin K is the nutrient spinach is best known for, and for good reason. One cup of raw spinach contains roughly 145 mcg of vitamin K1 (phylloquinone), which already exceeds the adequate daily intake of 120 mcg for adult men and 90 mcg for adult women. This vitamin is essential for blood clotting. Your body needs it to produce four of the 13 proteins involved in stopping a wound from bleeding. It also plays a role in building and maintaining bone density.
If you take blood thinners, this matters to you. Vitamin K works directly with the clotting mechanism those medications are designed to slow down. Consistency is key: rather than avoiding spinach entirely, most people on blood thinners are advised to eat a steady amount of vitamin K each day so their medication dose can be calibrated accordingly.
Vitamin A and Beta-Carotene
One cup of raw spinach provides about 56% of the daily value for vitamin A, primarily in the form of beta-carotene. Your body converts beta-carotene into active vitamin A as needed, which supports your immune system, skin cell turnover, and vision, particularly your ability to see in low light.
Because vitamin A is fat-soluble, your body absorbs significantly more of it when you eat spinach alongside a source of healthy fat. Pairing your spinach with avocado, a drizzle of olive oil, nuts, seeds, or fatty fish like salmon makes a real difference in how much of this vitamin you actually take in.
Vitamin C
Raw spinach provides a moderate dose of vitamin C, about 14 mg per cup, which covers roughly 15% of the daily value. Vitamin C supports collagen production (important for skin and joint health), helps your immune system function, and acts as an antioxidant. It also improves your absorption of the non-heme iron found in plant foods like spinach, which is one reason a squeeze of lemon juice on a spinach salad is more than just a flavor choice.
Heat breaks down vitamin C quickly, so raw or lightly cooked spinach retains more of it than heavily boiled spinach does.
Folate and Other B Vitamins
Spinach is one of the richest plant sources of folate (vitamin B9), delivering about 58 mcg per raw cup, or roughly 15% of the daily value. Folate is critical for DNA synthesis and cell division, which makes it especially important during pregnancy. Adequate folate intake before and during early pregnancy reduces the risk of neural tube defects in developing babies.
Spinach also contains smaller amounts of riboflavin (B2), B6, and thiamine (B1). These B vitamins help your body convert food into energy and support nervous system function. None of them appear in blockbuster quantities in a single serving, but they add up when spinach is part of a regular diet.
Vitamin E
A cup of raw spinach provides a small but useful amount of vitamin E, roughly 6% of the daily value. Vitamin E functions as an antioxidant, protecting cell membranes from damage. Like vitamins A and K, it’s fat-soluble, so the same strategy of pairing spinach with healthy fats applies here too.
Lutein and Zeaxanthin
These aren’t vitamins in the traditional sense, but they’re worth mentioning because spinach is one of the top dietary sources. One cup of raw spinach contains about 3,659 mcg of lutein and zeaxanthin combined. Cooking concentrates them: a cup of canned spinach contains over 20,000 mcg. These compounds accumulate in the retina, where they filter high-energy blue light and act as antioxidants. Higher dietary intake is associated with a lower risk of age-related macular degeneration, one of the leading causes of vision loss in older adults.
Minerals Worth Noting
Spinach also contains iron, calcium, magnesium, and potassium. On paper, the iron and calcium numbers look impressive. In practice, spinach contains high levels of oxalic acid, a natural compound that binds to calcium and iron and significantly reduces how much your body can absorb. You absorb far less calcium from spinach than from dairy or fortified foods, and less iron than from meat or legumes.
Cooking spinach reduces some of its oxalate content, which modestly improves mineral absorption. Pairing cooked spinach with a vitamin C source (like tomatoes or lemon juice) further helps with iron uptake. The magnesium and potassium in spinach are less affected by oxalates, making spinach a more reliable source of those two minerals.
Raw vs. Cooked: What Changes
Cooking spinach concentrates many of its nutrients because the leaves shrink dramatically. A cup of cooked spinach contains several times the vitamin K, vitamin A, folate, and lutein found in a cup of raw spinach, simply because you’re eating far more leaves. Cooking also breaks down cell walls, making some nutrients more accessible.
The tradeoff is vitamin C, which degrades with heat. If you’re eating spinach primarily for vitamin C, raw is better. For nearly everything else, cooked spinach delivers more per serving. A mix of both raw and cooked spinach across your week gives you the broadest benefit.