How much iron is in coriander vs spinach?

December 18, 2025 •

4 min read

Despite popular myth, spinach is not a superior source of usable iron due to its high oxalate content. A comparative look at how much iron is in coriander vs spinach reveals that while spinach contains slightly more iron by volume when cooked, its absorption is significantly hindered, a crucial factor in nutritional value.

Quick Summary

This nutritional comparison examines the iron content and bioavailability in coriander and spinach, including the impact of absorption inhibitors like oxalates and enhancers like Vitamin C.

Key Points

Total Iron vs. Bioavailability: Spinach's high total iron is deceptive; its bioavailability is very low due to oxalates.
Oxalate Inhibitors: Spinach contains very high levels of oxalates that block iron absorption, whereas coriander's oxalate content is much lower.
Non-Heme Iron Source: Both coriander and spinach provide non-heme iron, which is generally less absorbed than heme iron from animal sources.
Enhance Absorption with Vitamin C: Adding a source of Vitamin C, such as lemon juice or tomatoes, can significantly boost the absorption of non-heme iron from both greens.
Cooking Matters: Boiling spinach and draining the water can reduce its oxalate levels, making its iron more accessible.
Historical Myth: The perception of spinach as an iron superfood stemmed from a misplaced decimal point in a 19th-century study.
Coriander's Advantage: For raw consumption, coriander offers better iron absorption due to its lower oxalate content, despite having a similar raw iron amount.

Demystifying the Iron Content in Leafy Greens

For decades, spinach has been widely regarded as an iron powerhouse, thanks in part to an infamous scientific error and the fictional character Popeye. However, the real story behind the iron content in leafy greens like spinach and coriander is far more nuanced. It’s not just about the total amount of a mineral but how much of it the body can actually absorb and utilize, a concept known as bioavailability. For plant-based, or non-heme, iron sources, this is especially important.

The Raw Iron Numbers: Coriander vs. Spinach

When comparing the iron in coriander versus spinach, especially raw, it is important to consult current, reliable nutritional databases, which provide more accurate figures than historical data. While figures can vary slightly depending on the specific variety, cultivation method, and reference database, an approximate comparison is illuminating.

For example, raw coriander leaves typically contain around 1.8 to 5.3 milligrams (mg) of iron per 100 grams, with some sources listing figures in the lower end of this range. In contrast, raw spinach contains a comparable or slightly higher amount, with figures often cited between 2.1 and 3.2 mg per 100 grams, depending on the variety. However, this raw comparison doesn't account for the most significant factor affecting their nutritional impact: absorption.

The Crucial Role of Bioavailability and Oxalates

Here is where the comparison becomes truly revealing. The iron in all plant-based foods is non-heme iron, which is not as easily absorbed as the heme iron found in meat. Furthermore, both spinach and coriander contain compounds called oxalates, which bind to iron and other minerals, preventing their absorption. The concentration of oxalates, however, differs dramatically.

Spinach is notoriously high in oxalates, with a concentration that is far greater than in coriander. This high oxalate content is the primary reason why the iron in spinach has very low bioavailability; studies have shown that as little as 2% to 6% of the non-heme iron in spinach is actually absorbed by the body. By contrast, coriander has a much lower oxalate content, making the iron it contains more accessible to the body. While coriander contains less total iron by volume, the bioavailability is arguably better.

The Impact of Cooking and Volume

Cooking methods also play a significant role, particularly with spinach. When spinach is cooked, a few things happen:

Volume Reduction: A large volume of raw spinach wilts down to a small, dense serving. This means a single cup of cooked spinach contains a far more concentrated dose of nutrients than a cup of raw spinach.
Oxalate Reduction: Cooking, especially boiling, can help reduce the oxalate content of spinach, thereby improving iron absorption.

For coriander, which is more often used as a garnish or in uncooked applications like chutneys and salads, this effect is less pronounced. However, its lower natural oxalate levels mean its iron is more readily available from the start, especially when consumed raw.

How to Maximize Non-Heme Iron Absorption

Regardless of which green you choose, there are effective strategies to boost your body’s iron uptake. Pairing these foods with Vitamin C is the most impactful method.

Best practices for enhancing non-heme iron absorption:

Pair with Vitamin C: Squeeze lemon juice over your spinach salad or add chopped tomatoes to a dish with coriander. The ascorbic acid in Vitamin C aids in converting non-heme iron into a form that is more easily absorbed.
Cook Smartly: For spinach, cooking it can reduce the oxalate load. Boiling and draining is particularly effective.
Avoid Inhibitors: Avoid consuming calcium-rich foods like dairy or beverages high in tannins, like tea and coffee, at the same time as your iron-rich meal, as they can inhibit absorption.
Use Cast Iron Cookware: Cooking with a cast-iron skillet can increase the iron content of your food naturally.

Comparison Table: Coriander vs. Spinach


Feature	Coriander (Raw)	Spinach (Raw)
Iron Content (per 100g)	Approx. 1.8 - 5.3 mg	Approx. 2.1 - 3.2 mg
Bioavailability	Relatively better than spinach due to lower oxalates	Very low (2-6%) due to high oxalate content
Oxalate Content	Lower concentration	Very high concentration
Best Preparation for Iron	Best raw or lightly cooked with Vitamin C source	Best cooked (boiled and drained) with Vitamin C source
Flavor Profile	Distinct, citrusy, and fresh	Earthy, often bitter when raw

Conclusion: Which is Better for Iron?

Ultimately, the question of which is better for iron is not straightforward and depends heavily on preparation and consumption habits. While raw spinach may have a comparable or slightly higher total iron count than raw coriander, the high concentration of oxalates means its bioavailability is extremely poor. In contrast, coriander's lower oxalate levels make its iron more readily absorbed, particularly when paired with a Vitamin C source like lemon. For those seeking to boost their iron intake from greens, strategically cooking spinach (e.g., boiling and draining) and always pairing it with Vitamin C is key. For a more bioavailable raw option, coriander and its lower oxalate profile offers an advantage. Diversifying your diet with other high non-heme iron sources like lentils, seeds, and fortified cereals is also recommended for a comprehensive nutritional approach.

Visit the Canadian Digestive Health Foundation for more information on iron absorption.

Frequently Asked Questions

Coriander is generally better for iron absorption, especially when raw, because it has significantly lower levels of oxalates compared to spinach. The high oxalate content in spinach severely limits the bioavailability of its iron.

To increase iron absorption from spinach, you should cook it, preferably by boiling and draining, to reduce the oxalate content. You should also consume it with a food high in Vitamin C, such as lemon juice, bell peppers, or strawberries.

Cooking spinach does not increase its actual iron content, but it makes the iron more concentrated per volume and improves its bioavailability by reducing oxalates.

The iron in spinach is poorly absorbed because it is non-heme iron, and spinach contains high levels of oxalic acid. The oxalic acid binds to the iron, preventing the body from absorbing it effectively during digestion.

Yes, coriander contains oxalates, but at much lower levels than spinach. This is why coriander's iron is more readily available for absorption.

Non-heme iron is the form of iron found in plant-based foods. It is less efficiently absorbed by the body compared to heme iron, which is found in animal products.

Combining plant-based iron sources with foods high in Vitamin C, like citrus fruits, bell peppers, and tomatoes, can significantly boost absorption. Conversely, avoiding coffee, tea, and calcium-rich dairy during an iron-rich meal can help.