Is Spinach Really A Good Source Of Iron? A Dietitian Explains
Spinach has long had a reputation as an iron powerhouse. You can absorb some iron from spinach, but it’s a pretty inefficient source of the mineral (despite what Popeye told us). Here's why.
Spinach contains non-heme iron
A cup of cooked spinach contains about 6 milligrams of iron, while a cup of raw spinach contains closer to 1 milligram. It's recommended that that women eat around 18 milligrams of iron a day and men get around 8 milligrams daily. At first glance it seems like a hearty source of the mineral. But spinach is a source of non-heme iron.
Non-heme iron is a type of iron found specifically in plant foods (and heme iron is found in animal proteins). The body generally absorbs non-heme iron far less efficiently than heme iron, which is found in animal foods like meat, poultry, and seafood. So, you'll only absorb a fraction of that 6 milligrams of iron from cooked spinach.
Oxalates can make absorption more difficult
Spinach also contains relatively high levels of oxalates, naturally occurring compounds that can bind to minerals and reduce their absorption. Oxalates can bind to minerals in the digestive tract, forming compounds that are less soluble, and therefore, less available for absorption.
Oxalates may make iron absorption more challenging. While some research suggests that oxalate-rich foods1, including spinach and certain fruits, may have little effect on the absorption of non-heme iron, there's still no downside to pairing these nutritious foods with ingredients that can enhance iron absorption.
How to get more iron from spinach
If you're eating spinach, be sure to pair it with a source of vitamin C. Vitamin C can enhance the absorption of non-heme iron, helping your body get more from plant-based sources.
Try adding spinach to a salad with bell peppers and strawberries, serving it alongside tomatoes or citrus, or simply squeezing some lemon juice over cooked spinach.
Cooking can help reduce the oxalate content of spinach2, particularly when the spinach is boiled and the cooking water is discarded. This is because some soluble oxalates leach out into the water during cooking. However, cooking doesn't remove all oxalates.
Hot to get more iron
If you're trying to increase your iron intake, don't rely on spinach alone. A varied diet that includes a mix of heme and non-heme iron sources can help you meet your needs.
Some of the richest sources of heme iron include:
- Oysters and other shellfish
- Beef and other red meat
- Organ meats, particularly liver
- Sardines
- Tuna
- Chicken and turkey
Plant foods do still contribute a significant amount of iron to your overall dietOther good non-heme sources of iron include.
- Lentils
- Beans (including white beans, kidney beans, and chickpeas)
- Tofu and tempeh
- Pumpkin seeds
- Cashews
- Quinoa
- Spinach and other leafy greens
- Iron-fortified breakfast cereals
That doesn't mean spinach is unhealthy—or that you need to avoid it. Far from it. Spinach is still a nutrient-dense source of fiber, folate, vitamin K, carotenoids, and other beneficial plant compounds. It just shouldn't be your only strategy for getting enough iron.
What about iron supplements?
If you have low iron levels (most accurately measured via a ferritin blood test), iron supplements are often a crucial part of correcting it. Low iron levels are especially common in women, due to monthly blood loss from menstruation, high physical demands on the body, and oftentimes lower intake of heme iron sources than men.
The right dose of an iron supplement will vary depending on your, and high-dose iron supplements should always be overseen by a physician. Look for supplements that provide chelated iron, as they're often more gentle on the stomach. This multivitamin is a great option to support your iron intake on a daily basis. It provides 9 milligrams of chelated iron. It also has vitamin C to support absorption and 31 other vitamins, minerals and antioxidants.
The takeaway
Yes, you can absorb iron from spinach, but it's not the best source, thanks in part to its non-heme iron and high oxalate content. To get enough iron, focus on a varied diet that includes both heme and non-heme sources, and pair plant-based sources with vitamin C to help enhance absorption.
