What vegetable is the highest source of iron?

December 5, 2025 •

3 min read

While spinach is a commonly cited source of iron, legumes like lentils and soybeans often contain significantly higher amounts per serving. For those on a vegetarian or vegan diet, knowing what vegetable is the highest source of iron and how to properly absorb it is crucial for maintaining good health.

Quick Summary

This article explores the highest sources of plant-based iron, debunking the spinach myth and highlighting more potent options like lentils and soybeans. It details effective strategies for enhancing non-heme iron absorption.

Key Points

Top Source: Legumes like lentils and soybeans provide the highest concentration of iron among plant-based foods, surpassing leafy greens like spinach.
Spinach Myth: The high iron content of spinach is often exaggerated; while healthy, other vegetables and legumes offer more iron per serving.
Maximize Absorption: To increase your body's absorption of plant-based (non-heme) iron, pair your meals with foods rich in vitamin C, such as bell peppers or citrus.
Preparation Matters: Soaking, sprouting, or fermenting legumes and grains helps reduce compounds that inhibit iron absorption, improving bioavailability.
Limit Inhibitors: Avoid consuming tea, coffee, or calcium-rich foods at the same time as your iron-rich meals, as they can interfere with absorption.
Variety is Key: A diverse diet including a mix of different iron-rich vegetables, legumes, seeds, and nuts is the best way to ensure adequate iron intake.

Debunking the Spinach Myth: Lentils and Soybeans Lead the Way

For years, spinach has been a celebrated symbol of iron-rich vegetables, a misconception largely popularized by a misplaced decimal point in a 19th-century scientific study. While spinach does contain iron, many other plant-based foods, including specific vegetables and legumes, offer a significantly higher concentration per serving. Legumes, in particular, consistently outperform leafy greens, making them a powerhouse for plant-based iron intake.

The Iron-Rich Power of Legumes

Legumes, which are often classified as vegetables in nutritional guidelines, are the true champions of plant-based iron. A single cup of cooked lentils provides approximately 6.6 mg of iron, which is considerably more than the amount found in the same volume of cooked spinach. Soybeans are another stellar source, with a cup of raw soybeans offering around 9.1 mg of iron. For those who consume fermented soy products, natto is a clear winner, containing an impressive 15.1 mg of iron per cup. Other iron-packed legumes include white beans (6.6 mg per cooked cup) and chickpeas (4.7 mg per cooked cup).

Other Notable High-Iron Vegetables

Beyond the leading legumes, several other vegetables offer substantial amounts of non-heme iron. While their iron content may be less concentrated, they still make valuable contributions to an iron-rich diet, especially when paired with vitamin C to aid absorption.

List of high-iron vegetables:

Spinach: A cup of cooked spinach contains approximately 5.7 mg of iron, and its high vitamin C content can improve absorption.
Swiss Chard: This leafy green offers about 3.9 mg of iron per cooked cup.
Beet Greens: These often-overlooked greens provide 2.7 mg of iron per cooked cup.
Potatoes: A large baked potato with the skin contains approximately 1.9 mg of iron.
Broccoli: This versatile vegetable offers around 1 mg of iron per cooked cup.

Comparison of Iron-Rich Foods


Food (Cooked)	Iron per Cup (mg)	Plant-Based?	Absorption Boosters
Lentils	6.6	Yes	Vitamin C, Soaking
White Beans	6.6	Yes	Vitamin C, Soaking
Soybeans (Raw)	9.1	Yes	Fermentation, Soaking
Spinach	5.7	Yes	Vitamin C
Swiss Chard	3.9	Yes	Vitamin C
Kidney Beans	5.2	Yes	Vitamin C, Soaking

How to Maximize Iron Absorption from Plants

Since non-heme iron from plant sources is not as easily absorbed as heme iron from meat, strategic eating is key. Cooking methods, food pairings, and preparation techniques can significantly increase your body's ability to utilize this vital mineral.

Pair with Vitamin C

One of the most effective strategies is to combine iron-rich foods with a source of vitamin C. Vitamin C captures non-heme iron and stores it in a more easily absorbable form.

Excellent vitamin C pairings:

Squeeze lemon juice over a spinach salad.
Add diced bell peppers or tomatoes to your lentil soup or bean chili.
Enjoy a side of broccoli with a meal rich in legumes.

Preparation Methods

Certain preparation techniques can reduce compounds that inhibit iron absorption, such as phytates found in grains and legumes.

Soaking and Sprouting: Soaking and sprouting grains and legumes before cooking helps break down phytates, leading to better iron absorption.
Fermentation: Fermented products like tempeh and natto have higher bioavailability due to the breakdown of phytates during fermentation.
Cooking in Cast Iron: Cooking acidic foods in a cast-iron skillet can increase the iron content of your meal.

Limit Inhibitors

Some foods and drinks can hinder iron absorption, so it's best to avoid them around the same time you eat iron-rich meals.

Tea and Coffee: Tannins and polyphenols in tea and coffee can bind to iron. Have these beverages between meals instead.
Calcium-Rich Foods: Calcium can interfere with non-heme iron absorption. If you take calcium supplements or consume dairy, consider spacing them out from your main iron source.

Conclusion

While leafy greens like spinach are a healthy part of any diet, they are not the definitive answer to the question, what vegetable is the highest source of iron? Instead, legumes such as lentils, soybeans, and white beans take the top spot, offering a higher concentration of the mineral per serving. By incorporating a variety of these powerhouse plant foods into your diet and applying simple strategies to boost absorption—like pairing with vitamin C and proper preparation—you can ensure you maintain healthy iron levels and combat deficiencies naturally. For those on a strictly plant-based diet, this knowledge is invaluable for achieving a balanced and nutrient-dense nutritional profile. For more specific nutritional information, consult the USDA FoodData Central.

Disclaimer: Always consult a healthcare provider or a registered dietitian before making significant changes to your diet, especially if you have concerns about iron deficiency.

Frequently Asked Questions

No, while spinach does contain iron, the idea that it is the highest source is a long-standing myth based on a historical error. Legumes like lentils and soybeans typically offer a higher iron content per serving.

You can significantly increase your body's absorption of plant-based iron by pairing iron-rich foods with a source of vitamin C. Squeezing lemon juice over cooked greens or adding tomatoes to a lentil dish are effective methods.

Because the non-heme iron found in plant foods is less bioavailable than the heme iron in meat, it is often recommended that vegetarians aim for a higher daily iron intake to compensate for lower absorption.

Among commonly available legumes, natto (fermented soybeans) contains an exceptionally high amount of iron, with over 15 mg per cup. Cooked lentils and white beans also offer a potent dose, with approximately 6.6 mg per cup.

Certain substances can inhibit iron absorption. It is best to avoid consuming tea, coffee, and calcium-rich foods like dairy or supplements at the same time as an iron-rich meal.

Cooking can sometimes affect the concentration and availability of iron. Cooking vegetables like spinach can reduce their volume, concentrating the iron content per cup. Proper preparation like soaking can also help reduce absorption inhibitors.

Besides greens like spinach and Swiss chard, other good vegetable sources of iron include baked potatoes with the skin, beet greens, and concentrated tomato products.