The Best Sources of Iron, According to an RD

Iron plays numerous important functions in the body. The National Institutes of Health Office of Dietary Supplements explains that iron is an important component of hemoglobin, the protein in red blood cells that helps transport oxygen from your lungs to your organs and tissues. It’s also a component of myoglobin, which carries oxygen to the muscles making it essential for exercise performance. Additionally, the body calls upon iron for cell function, metabolism, and creating some hormones. 

And you need to keep your iron supply steady. Since red blood cells have such a short lifespan (about 120 days), the body requires a constant supply of iron to rebuild hemoglobin. A lack of sufficient iron can contribute to iron deficiency anemia, meaning your red blood cells don’t transport enough oxygen throughout your body. Surprisingly, iron is the most common nutrient deficiency in the world–and women are about twice as likely as men to suffer from anemia and poor iron status. 

A Lack of Iron Can Wreak Havoc on the Body

Low levels of iron can leave you feeling physically tired and weak, impair mental function, and weaken the immune system, or worse. 

A 2021 study published in the journal ESC Heart Failure linked iron deficiency with a 24 percent higher risk of heart disease, a 26 percent higher risk of death due to cardiovascular disease, and a 12 percent greater risk for all-cause mortality. The study, based on data from more than 12,000 European adults, suggested that sufficient levels of iron may prevent about 1 in 10 new cases of heart disease in middle-aged adults.

How Much Iron Do You Need?

The Institute of Medicine of the National Academy of Sciences recommends that premenopausal women consume 18 mg of iron per day. After menopause, women’s iron needs drop to the same level as men’s: 8 mg per day. But pregnancy raises the daily iron need to a lofty 27 mg to accommodate the developing baby’s needs. 

Try These Top Sources of Iron

While your doctor may prescribe an iron supplement if your levels test low–as this is the most efficient way to bring numbers back up–there are certain iron-packed foods you can eat to help make sure you’re pumping enough iron into your diet. 

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1. Beef Liver

When it comes to red meat, liver is the iron superstar. According to the U.S. Department of Agriculture, each 3-ounce serving of cooked liver delivers more than 5 mg of the mineral in a highly absorbable form. That’s more than most cuts of steak you’ll find at the butcher. 

Liver is also exceptionally rich in vitamin B12–so much so that each ounce of beef liver supplies nearly 400 percent of the daily need for the nutrient. 

And in our new reality of rising food costs, it’s helpful that liver is still much more budget-friendly than most other red meat options.

Just note that liver contains about six times the Recommended Daily Intake for vitamin A, a nutrient that can pose a toxicity risk if consumed frequently in great quantities. So, you can use liver in your diet one to two times a week to get more iron, but don’t make it a daily staple for the risk of going overboard on vitamin A.  

How to Prepare Beef Liver

Perhaps some haphazard preparation has left you put off by this organ meat. The key is to cook liver quickly in a hot skillet so the outside sears while the interior remains tender and almost velvety. Soaking liver in water spiked with salt and lemon juice can help dampen the strong flavor and tenderize the meat. 

If you’re not a fan of beef liver, you can also try chicken liver. Most people find that chicken liver has a more subtle flavor than beef liver and is also an excellent source of cost-effective iron. 

2. Oysters

These briny shellfish are iron standouts. Three cooked ounces of oysters contain nearly 7 mg of highly absorbable heme iron. Ounce for ounce, that’s even more than beef, while at the same time containing significantly less saturated fat than most red meat sources. 

How to Prepare Oysters

For most of us, the thought of shucking oysters at home is enough to keep them off the menu on any sort of regular basis. That’s where ultra-convenient canned oysters come to the rescue. This no-prep-required alternative is great tossed on salads, grain bowls and pizza; worked into pasta dishes, chowders and soups; or simply forked up straight from the can for a high-protein snack.

3. Teff

Perhaps a fondness for this ochre poppy seed-sized grain might be the secret sauce that helps Ethiopia routinely turn out some of the best runners on the start line. In contrast to most grains, teff is naturally high in iron–a quarter cup of dry teff delivers about 20 percent of the daily requirement. In comparison, the same amount of quinoa and oats have only 11 percent and 5 percent, respectively. 

One study led by scientists at Manchester Metropolitan University in England found females who typically consumed insufficient amounts of iron and had low iron levels experienced noticeable improvements in their iron levels after consuming bread made from teff every day for six weeks. This one food substitution elevated the subjects’ average daily iron intake from 10.7 mg per day to 18.5 mg, which is the amount women should strive for each day.

A separate investigation in the journal Frontiers of Nutrition determined that certain cereal grains in the millet family–including teff–can help people raise their hemoglobin and serum ferritin levels. This suggests some whole grains are higher in iron than others and perhaps more of us would benefit by consuming a greater variety of grains than just wheat or rice. The study authors noted that some preparation methods, including germination and fermentation, improved iron bioavailability. 

Teff is also rich in many other essential micronutrients that can benefit your health including manganese, thiamine, magnesium, and bone-strengthening calcium.

How to Prepare Teff

The starch in teff causes the grains to cling together once cooked, so you can try using it like polenta or as breakfast porridge with a similar consistency to cream of wheat (season it with cinnamon and top with berries and nuts). Teff flour can up the nutritional ante of cookies, pancakes, waffles, and tart crusts.

4. Tempeh

If you’re striving to eat more plant protein, tempeh is a nutritional win. Tempeh is made using fermented soybeans. Not only is meaty tempeh higher in protein and fiber than tofu, but it’s also a reliable source of iron. Soybeans are an iron source, so by extension, so is tempeh. 

But many plant-based foods including legumes contain various so-called anti-nutrients including phytates and oxalates that can make certain micronutrients including iron less bioavailable to us. However, what you need to know is that research shows the fermentation process used to make some foods, including tempeh, can improve nutrient absorption by reducing anti-nutritional factors. So, tempeh could be a better source of iron than other legume foods that are not fermented or the new wave of meat alternatives including burgers. 

How to Prepare Tempeh

You can treat tempeh almost like any meat-based protein. It can be marinated before cooking (and it’ll soak up flavor well!), and it sears well when sliced into slabs. You can also grate tempeh and turn it into crumbles to create ground “meat” that works for meatballs, in chilis and soups, or even as taco filling. 

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5. Molasses

If you have a sweet tooth, consider satisfying it with molasses. The sticky, robust flavored sweetener is a surprising source of dietary iron, providing 1 to 1.5 mg in a 1-tablespoon serving. That’s much more than other sweeteners on the market, including maple syrup. 

While data is still unclear, it appears that stronger-flavored blackstrap molasses may contain higher levels of iron than lighter versions. 

Just don’t believe any online chatter that taking molasses by the spoonful is a great way to override anemia. You’d have to take a lot of the sweetener for this to occur, and that would put you in the sugar red zone–not to mention be a little gross. And there remains scant research regarding the impact molasses can have on iron status. Instead, think of it as a semi-sweet way to sneak a little iron boost into your diet.

How to Use Molasses

You can use molasses as a sweetener for baking, oatmeal, and homemade energy bars and balls. Use it for DIY barbecue sauces and glazes for meat and, of course, in a batch of baked beans. 

6. Fortified Cereals

If you are a cereal lover, it could give you a good dose of iron. Some breakfast cereals contain a high amount of iron as they’ve been fortified with the mineral–but very few contain useful amounts naturally. Iron-fortified cereals typically have 3 mg to 18 mg of iron per serving. 

There are two different forms of dietary iron. Heme iron, from animal sources like meat, seafood, and milk, is more easily absorbed by the body. Non-heme iron, from plant sources like fortified cereals, dark leafy greens, seeds, and legumes, is a more abundant form. However, it’s absorbed at a lower rate. You can improve your absorption of iron from plant foods by pairing them with foods high in vitamin C such as strawberries, citrus fruits, tomatoes, and bell peppers. A study in the British Journal of Nutrition found that women who ate iron-fortified cereal with kiwi fruit, which is especially rich in vitamin C, were able to raise their iron levels. 

So, if you’re consuming any iron-rich plant foods at a meal, such as fortified cereal with breakfast, make sure there’s also a source of vitamin C at the table. And be sure to slurp up any leftover milk; some of the added iron may have seeped into the liquid. It’s worth noting that an adaptive response of our bodies is to increase non-heme iron absorption when iron levels are low. 

Just be sure to read food labels carefully and choose a breakfast cereal that has good iron content, but is low in added sugar.

7. Tahini

Made from ground-up iron-rich sesame seeds, tahini is a great way to add more iron into your diet. Each tablespoon serving supplies about 3 mg of iron, which is roughly six times the amount you’d get from almond butter and eight times what a spoonful of peanut butter will give you. 

Other nutritional highlights include dietary fiber and the bone-benefiting duo calcium and phosphorus. 

How to Use Tahini

Rich and toasty-tasting, the creamy spread does wonders to all manners of sweet and savory dishes. Spoon it over roasted vegetables and oatmeal, use it in baked goods including cookies, blondies, and muffins, turn it into a creamy salad dressing, and blend into smoothies for a little richness. 

8. Cast Iron

Yep, you read that right: You can actually get iron from cooking with cast iron! Not only can you use it for everything from browning meat to preparing frittatas to slow-cooking stews, but cooking food in cast iron cookware also imparts the mineral into your food. 

A systematic review found that cooking in cast iron cookware can increase blood hemoglobin levels in people who often prepare foods in the pans; it can also boost the (non-heme) iron content of foods. Cooking meat and vegetables in cast-iron resulted in especially notable increases–in some cases, the participants’ iron intake doubled. 

Just keep in mind that several variables will impact the increase in iron content of food, including preparation technique and duration of cooking. Likely, iron content increases with longer cooking times, frequent stirring, and more food surface area contact. Acidic foods like tomatoes may also result in more iron leaching from pan to food. 

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