Focus On Iron

By Carol Harrison, RD

What To Eat, Cast Iron Cooking And More

Are you getting enough iron? Many Canadians aren’t—even more than previously thought, according to Health Canada research published earlier this year. Females of reproductive age are most at risk—it’s estimated that approximately one in three teenage girls and adult women (19-50 years old) is iron deficient.¹

If you’re concerned that you or another family member may not be getting enough iron, eating iron-rich foods daily should be a top priority. Using cast iron cookware can also help boost the absorption of iron from these foods. This popular cookware adds a small amount of iron to foods as you prepare them, making it an easy and affordable way to increase iron intake.

How much iron do we need?

Everyone needs adequate iron for optimal health. Here’s how much iron we should eat daily at different life stages:

Daily Iron Requirements

Children
7-12 months	11 mg
1-3 years	7 mg
4-8 years	10 mg
9-13 years	8 mg
Teens (14 to 18 years)	11 mg (boys) 15 mg (girls)

Adults
19-50 years	8 mg (men) 18 mg (women)
51 years and over	8 mg
During Pregnancy	27 mg

Women, especially, need to pay attention to their iron intake, as we need 18 mg daily. During pregnancy, that rises to 27 mg—iron is vital for a baby’s development.

Cooking with cast iron

You can find cast iron skillets, frying pans, griddles, dutch ovens, bakeware and even woks. Many home cooks like using cast iron because it’s durable and it retains heat well.

Cast iron cooking adds “non-heme” iron, the same type found in eggs and plant sources like spinach, enriched pasta or lentils. Non-heme iron is less well absorbed by the body (2%–20%) than heme iron (15%–35%)², the type of iron in beef, fish and poultry. (See below for tips on enhancing the absorption of non-heme iron.)

The amount of iron that cast iron cookware adds to food will vary depending on the food’s:

• acidity
• moisture
• cooking time

One study found that 90% of foods cooked in cast iron had more iron.³ The researchers cooked 20 kinds of foods in both cast iron and non-iron cookware, and they found that acidic foods with high moisture content, such as applesauce and spaghetti sauce, absorbed the most iron. Using cast iron cookware increased the iron in applesauce by 7 mg, and spaghetti sauce had 3 to 5 mg more iron. Scrambled eggs gained 3 mg of iron. The iron content of dry foods that are not acidic also increased but in smaller amounts: 1.5 mg for fried eggs and 1 mg for pancakes.

Foods cooked longer absorbed more iron. Beef stew, already an iron-rich food, had 2.8 mg more iron after cooking in cast iron. Another study found similar results, even after using the cast iron cookware 50 times.⁴

6 ways to get more iron from food

The findings of the research mentioned above are promising, but we shouldn’t rely solely on cast iron cookware to meet our iron needs—what matters most is what we eat. In fact, recent Canadian research shows that more frequent red meat consumption is the only dietary factor associated with better iron status in women.⁵

Here are six other ways to boost your iron intake:

1. Eat a variety of iron-rich foods from both animal and plant sources every day.
2. Prioritize foods with sources of well-absorbed heme iron (meat, poultry, seafood).
3. Boost the non-heme iron you absorb from plant sources by 150% by pairing them with meat, poultry and seafood.⁶
4. Boost the amount of non-heme iron you absorb from plant sources by adding vitamin-C-rich foods to the same meal (broccoli, red peppers, citrus fruits, potatoes, tomatoes).⁷
5. To increase the amount of iron your body absorbs from a meal, wait one to two hours before drinking tea or coffee or taking calcium supplements.⁸
6. Prepare foods in cast-iron cookware. You’ll get the most iron from moist, acidic foods cooked slowly, such as chili, stew and spaghetti sauce.

Why Iron Is So Important

Check out some of these cast iron recipes:

References

1. Cooper M, Bertinato J, Ennis JK et al. Population Iron Status in Canada: Results from the Canadian Health Measures Survey 2012-2019. J Nutr. 2023 May;153(5):1534–43. doi: 10.1016/j.tjnut.2023.03.012. Epub 2023 Mar 12. PMID: 36918146. https://pubmed.ncbi.nlm.nih.gov/36918146/ ↩︎
2. Monsen ER. Iron nutrition and absorption: dietary factors which impact iron bioavailability. J Am Diet Assoc. 1988 Jul;88(7):786–90. PMID: 3290310. https://pubmed.ncbi.nlm.nih.gov/3290310/ ↩︎
3. Brittin HC, Nossaman CE. Iron content of food cooked in iron utensils. J Am Diet Assoc. 1986 Jul;86(7):897–901. PMID: 3722654. https://pubmed.ncbi.nlm.nih.gov/3722654/ ↩︎
4. Cheng YJ, Brittin HC. Iron in food: effect of continued use of iron cookware. J Food Sci. 1991;56(2):584–5. https://doi.org/10.1111/j.1365-2621.1991.tb05331.x. https://ift.onlinelibrary.wiley.com/doi/10.1111/j.1365-2621.1991.tb05331.x ↩︎
5. Chang VC, Cotterchio M, Kotsopoulos J et al. Iron Status and Associated Factors among Canadian Women: Results from the Canadian Health Measures Survey. J Nutr. 2023 Mar;153(3):781–97. doi: 10.1016/j.tjnut.2022.10.011. Epub 2022 Dec 20. PMID: 36788041. https://pubmed.ncbi.nlm.nih.gov/36788041/ ↩︎
6. Engelmann MD, Davidsson L, Sandström B et al. The influence of meat on nonheme iron absorption in infants. Pediatr Res. 1998 Jun;43(6):768–73. doi: 10.1203/00006450-199806000-00009. PMID: 9621986. https://pubmed.ncbi.nlm.nih.gov/9621986/ ↩︎
7. Piskin E, Cianciosi D, Gulec S et al. Iron Absorption: Factors, Limitations, and Improvement Methods. ACS Omega. 2022 Jun 10;7(24):20441–56. doi: 10.1021/acsomega.2c01833. PMID: 35755397; PMCID: PMC9219084. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9219084/ ↩︎
8. Health Canada. Iron. May 2022. https://www.canada.ca/en/health-canada/services/nutrients/iron.html ↩︎