How to Increase Iron Absorption From Foods: A Simple Guide to Boosting Your Energy and Health

How to Increase Iron Absorption From Foods: A Simple Guide to Boosting Your Energy and Health

NOTE: If this topic interests you but your ears have more time than your eyes, you can listen to the full discussion on YouTube, where I dive deeper into it in this video.

Iron is a mineral your body needs to function properly. When your iron levels are too low, you might feel tired, foggy-headed, or get sick more often. You may even develop low thyroid function. Whether you eat mostly plants, a mix of everything, or mostly animal foods, you can still be at risk of low iron. This guide will help you understand why that happens—and what you can do about it.

Why You Might Have Low Iron

Low iron can happen for many reasons:

• A diet low in iron-rich foods 
• Inflammation in the body 
• Poor digestion, such as low stomach acid 
• An unhealthy gut microbiome
• Blood loss, including heavy periods or chronic low-level bleeding in the gut 

While you work on addressing these root causes, it’s important to also support your body by improving how well it absorbs iron from food. Getting enough iron helps boost your energy, supports your immune system, and keeps your brain and thyroid working properly.

Understand the Types of Iron: Heme, Non-Heme, and Elemental Iron

Iron in the diet comes in different forms, each with distinct absorption characteristics (Zeidan et al, 2024):

• Heme Iron: Found in animal products like red meat, poultry, and fish. It’s highly bioavailable and more easily absorbed by the body. 
• Non-Heme Iron: Found in plant foods such as vegetables, legumes, grains, nuts and seeds. Its absorption is more variable and influenced by other dietary factors. That means if you’re vegetarian or vegan, you’ll want to be more strategic about how you get and absorb iron. 
• Elemental Iron from Cookware: Cooking with cast iron pans can increase the iron content of your meals, especially in moist or acidic foods like tomato sauces. This occurs through elemental iron migration, where small amounts of iron leach into the food from the cookware (Cheng & Brittin, 1991). While not as bioavailable as heme iron, studies show that food prepared this way can help improve iron status, including vegetarians who are at risk of deficiency (Quintaes et al., 2007). While cooking with cast iron can be beneficial for increasing dietary iron, it is important to monitor iron intake to avoid toxicity, especially in young children who are more susceptible to iron overload.

Boosting Iron Absorption: What Works

1. Add Vitamin C to Meals

Vitamin C is one of the best ways to increase iron absorption. It keeps iron in a form your body can absorb and can cancel out some of the effects of absorption blockers (Hallberg et al, 1987). You don’t need massive amounts—25 to 50 mg of vitamin C per meal can make a big difference.

Here’s how you can get that amount from Whole Foods:

• Red Bell Peppers: Just 18–35 g (about 1/4 to 1/3 of a medium pepper) provides 25–50 mg of vitamin C (Sabolová & Kouřimská, 2020). 
• Yellow Bell Peppers: Exceptionally rich in vitamin C. Only 5–15 g is enough to meet the goal (Afnani et al., 2023). 
• Strawberries: 4–7 medium strawberries (36–71 g) deliver the desired dose (Sabolová & Kouřimská, 2020). 
• Citrus Fruits: A small orange, lemon, lime or half a grapefruit typically contains 25–50 mg of vitamin C. 

Tomatoes: Lower in vitamin C—you’d need very large amounts (over half a kilogram) to get 25–50 mg (Trifunschi et al., 2022).

Whenever possible, add these foods to meals with iron-rich ingredients. Think bell pepper strips with lentil salad, or lemon juice squeezed fresh over sautéed spinach.

2. Use Iron-Friendly Cooking Methods

Cooking in cast-iron pots or pans can increase the amount of iron in your food (Kumari et al., 2004).

Important Considerations When Using Cast Iron

Health Implications: Cooking with cast iron pans can be a helpful way to boost iron intake, especially for individuals at risk of deficiency. However, it’s important to monitor overall iron levels—too much iron can be harmful, particularly for young children who are more sensitive to iron overload.

Cooking Conditions Matter: The amount of iron that transfers from the pan to the food—known as elemental iron migration—depends on several factors. Acidic and moist foods (such as tomato sauces or stews), longer cooking times, and newer or less seasoned pans all tend to increase iron leaching.

Iron Form Matters: Even though elemental iron from cast iron is less bioavailable, using these pans regularly can still be a useful tool to support iron intake, particularly when combined with other iron absorption strategies. It’s usually a helpful supplement to dietary iron, but not enough on its own to correct a deficiency.

Vegetables With High Bioavailable Iron

Some green veggies have iron that your body can absorb more easily:

• Savoy cabbage: One of the top sources of plant-based iron (Rodriguez-Ramiro et al., 2019). 
• Fenugreek: High in vitamin C and iron, especially when mature (Khoja et al., 2020). 
• Amaranthus species (like A. tricolor): The leafy greens from this ancient grain have naturally higher iron (Rangarajan & Kelly, 1998). 

Pairing these veggies with vitamin C-rich foods (like tomatoes or lemon juice) can make a big difference (Nomkong et al., 2019).

3. Reduce Iron Blockers in Food

Some plant compounds, like phytates (in grains and legumes) and polyphenols (in tea and coffee), block iron from being absorbed.

To lower these blockers:

• Soak, sprout, or ferment beans and grains to reduce phytate levels (Gibson et al., 2014) 
• Avoid drinking tea or coffee with meals (Zijp et al., 2000) 

4. Include Vitamin A and Beta-Carotene

These nutrients help your body absorb non-heme iron by keeping it in a form that stays soluble (Garcia-Casal et al., 1998). 

Here are some natural foods high in Vitamin A and beta-carotene that you can incorporate into your diet:

1. Carrots – Rich in beta-carotene, which your body converts to Vitamin A. 
2. Sweet Potatoes – Packed with beta-carotene, providing a great source of Vitamin A. 
3. Spinach – A leafy green high in beta-carotene, which also supports eye and skin health. 
4. Kale – Another leafy green rich in beta-carotene for optimal Vitamin A intake. 
5. Butternut Squash – High in beta-carotene, perfect for soups, roasted dishes, or casseroles. 
6. Red Bell Peppers – Contain a significant amount of Vitamin A, alongside other vitamins and antioxidants. 
7. Liver (beef, chicken, or lamb) – Animal liver is one of the richest sources of preformed Vitamin A (retinol). 
8. Eggs – Particularly the yolks, which provide a good amount of preformed Vitamin A. 
9. Mangoes – A delicious tropical fruit that is high in Vitamin A. 
10. Cantaloupe – Another fruit that is rich in beta-carotene, providing a natural source of Vitamin A. 

5. Consider Prebiotics

Prebiotics like galacto-oligosaccharides (GOS) and fructo-oligosaccharides (FOS) feed the good bacteria in your gut. These have been shown to boost iron absorption from supplements by about 50% in people with low iron (Giorgetti et al., 2022).

You can get prebiotics naturally from a variety of whole plant foods that feed the beneficial bacteria in your gut. Great sources include garlic, onions, leeks, asparagus, Jerusalem artichokes, bananas (especially slightly green ones), and cooked and then cooled potatoes or rice, which contain resistant starch. Whole oats, apples with the peel, and dandelion greens are also rich in prebiotic fibers like inulin and fructooligosaccharides (FOS). Including a mix of these foods regularly in your meals can help support a healthy gut microbiome, which in turn enhances nutrient absorption—including iron—and supports overall digestive and immune health.

6. Make Meat Stock

Meat stock is a rich, flavorful liquid made by simmering meat (like beef, chicken, or lamb) and, optionally, bones with water and vegetables for several hours. It’s full of nutrients, including collagen, amino acids, and minerals like calcium and magnesium, which are released from the meat and bones during cooking.

For people who have gut issues, such as low stomach acid from chronic stress, meat stock can be helpful in improving iron absorption. Low stomach acid can make it harder for the body to absorb iron from food, especially nonheme iron (the type of iron found in plant-based foods). Meat stock, however, contains specific components, like amino acids and peptides, that can support digestion and help the body absorb iron more effectively. It can also soothe and heal the gut lining, which is especially important for those with digestive problems. By adding meat stock to meals, you can improve your chances of absorbing more iron, even if your stomach acid isn’t working as well as it should.

Not all animal proteins have the same effect on iron absorption. Research has shown that specific tissues in animals, such as beef, chicken, and fish, are particularly effective at improving nonheme iron absorption. This is not a general property of all animal proteins. For example, egg albumin (egg white) does not have the same impact (Hurrell et al., 1988). This suggests that certain components in meat play a significant role in enhancing iron absorption.

Making meat stock is simple and requires just a few basic ingredients. Here’s how to do it:

Ingredients:

• Meat and bones (beef, chicken, or lamb)
• Water to cover
• Vegetables: carrots, onions, and celery (optional, for extra flavor)
• Herbs: thyme, bay leaves, and peppercorns (optional)
• Salt to taste

Instructions:

• Place meat and bones in a large pot and add enough water to cover them completely.
• Add your vegetables and seasonings if using.
• Bring everything to a boil over high heat.
• Lower the heat and let it simmer gently for 4-6 hours, depending on how rich you want the stock.
• Occasionally skim off any foam that rises to the top.
• Once done, strain out the solids.

You’re left with a flavorful, nutrient-packed meat stock perfect for soups, stews, or as a base for cooking!

7. Try Fortified Foods or Supplements If Needed

If you have higher needs or your iron stores are low, iron-fortified foods or supplements might help. But check with a healthcare provider before starting supplements—too much iron can be harmful.

Tips for Vegetarians and Vegans

Even though plant-based diets tend to offer lower iron absorption, they can still work for you with smart planning. Here’s how:

• Eat iron-rich plant foods like legumes, tofu, dried fruits, and seeds 
• Add vitamin C-rich foods to every meal 
• Limit iron-blockers during meals 
• Use food prep techniques like soaking, sprouting, and fermenting to reduce phytates
• Cook with cast-iron pans to increase iron levels in foods 
• Monitor your iron status through regular blood tests, especially if you’re menstruating or have signs of inflammation 

Final Thoughts

Low iron can make you feel tired, foggy, and run down—but you can take action today. Whether you eat meat or follow a plant-based diet, increasing iron absorption is possible through simple changes in what and how you eat. Use the power of vitamin C, smart cooking, and careful food choices to help your body get the iron it needs to thrive.

References:

Zeidan, M., Azzopardi, L., Siguencia, A., et al. (2024). Heme vs non-heme iron: differences in dietary sources, absorption, and health outcomes. Journal of Human Nutrition and Dietetics. Advance online publication. PMID: 38312987

Cheng, Y., & Brittin, H. (1991). Iron in Food: Effect of Continued Use of Iron Cookware. Journal of Food Science, 56(2), 584–585. https://doi.org/10.1111/j.1365-2621.1991.tb05331.x

Quintaes et al. (2007). Mineral Migration and Influence of Meal Preparation in Iron Cookware on the Iron Nutritional Status of Vegetarian Students. Ecology of Food and Nutrition – ECOL FOOD NUTR. 46. 125-141. 10.1080/03670240701285079.

Hallberg, L., Brune, M., & Rossander, L. (1987). The role of vitamin C in iron absorption. International Journal for Vitamin and Nutrition Research. Supplement, 30, 103–108. PMID: 3302340

Sabolová, M., & Kouřimská, L. (2020). Vitamin C and nitrates contents in fruit and vegetables from farmers’ markets and supermarkets. Potravinarstvo Slovak Journal of Food Sciences, 14, 1124–1130. https://doi.org/10.5219/1347

Afnani, Fawait & Yanti, Jamilah & Pratiwi, Wiwit Sri Werdi. (2023). DETERMINATION OF VITAMIN C CONTENT IN BELL PEPPER (Capsicum annuum L.) WITH DIFFERENT PROTIC POLAR SOLVENT BY UV-VIS SPECTROSCOPY. Jurnal Kimia Riset. 8. 116-123. 10.20473/jkr.v8i2.44865.

Svetlana, Trifunschi & Zugravu, Corina & Munteanu, Melania & Borcan, Florin & Pogurschi, Elena. (2022). Determination of the Ascorbic Acid Content and the Antioxidant Activity of Different Varieties of Vegetables Consumed in Romania, from Farmers and Supermarkets. Sustainability. 14. 13749. 10.3390/su142113749.

Kumari, M., Gupta, S., Lakshmi, A. J., & Prakash, J. (2004). Iron bioavailability in green leafy vegetables cooked in different utensils. Food Chemistry, 86(2), 217–222. https://doi.org/10.1016/j.foodchem.2003.08.017

Rodriguez-Ramiro, I., Dell’Aquila, C., Ward, J., Neal, A. L., Bruggraber, S. F., Shewry, P. R., & Fairweather-Tait, S. J. (2019). Estimation of the iron bioavailability in green vegetables using an in vitro digestion/Caco-2 cell model. Food Chemistry, 301, 125292. https://doi.org/10.1016/j.foodchem.2019.125292

Khoja, K., Buckley, A., Aslam, M., Sharp, P., & Latunde-Dada, G. (2020). In vitro bioaccessibility and bioavailability of iron from mature and microgreen fenugreek, rocket and broccoli. Nutrients, 12(4), 1057. https://doi.org/10.3390/nu12041057

Rangarajan, A., & Kelly, J. (1998). Iron bioavailability from Amaranthus species: 1. In vitro dialysable iron for estimation of genetic variation. Journal of the Science of Food and Agriculture, 78(2), 267–273. https://doi.org/10.1002/(SICI)1097-0010(199810)78:2<267::AID-JSFA114>3.0.CO;2-1

Nomkong, R., Ejoh, R. A., Dibanda, R. F., & Gabriel, M. (2019). Bioavailability of iron and related components in cooked green leafy vegetables consumed in Cameroon. Food and Nutrition Sciences, 10(9), 1139–1152. https://doi.org/10.4236/fns.2019.109079

Gibson, R. S., Heath, A. L., & Szymlek-Gay, E. A. (2014). Is iron and zinc nutrition a concern for vegetarian infants and young children in industrialized countries? The American Journal of Clinical Nutrition, 100(Supplement_1), 459S–468S. PMID: 24898235

Zijp, I. M., Korver, O., & Tijburg, L. B. M. (2000). Effect of tea and other dietary factors on iron absorption. Critical Reviews in Food Science and Nutrition, 40(5), 371–398. PMID: 11029010

Garcia-Casal, M. N., Layrisse, M., Solano, L., Barón, M. A., Arguello, F., Llovera, D., Ramírez, J., & Leets, I. (1998). Vitamin A and beta-carotene can improve nonheme iron absorption from rice, wheat and corn by humans. The Journal of Nutrition, 128(3), 646–650. PMID: 9497178

Giorgetti, C., Ciferri, M., Buratta, L., Metelli, A., Gola, E., Cimini, E., Donati Zeppa, S., & Tiano, L. (2022). Prebiotics enhance iron absorption in anemic women: a randomized placebo-controlled trial. Frontiers in Nutrition, 9, 920238. https://doi.org/10.3389/fnut.2022.920238

Hurrell RF, Lynch SR, Trinidad TP, Dassenko SA, Cook JD. Iron absorption in humans: bovine serum albumin compared with beef muscle and egg white. Am J Clin Nutr. 1988 Jan;47(1):102-7. doi: 10.1093/ajcn/47.1.102. PMID: 3337027.