Iron is an essential mineral that plays a vital role in numerous bodily functions. Primarily, it’s a key component of hemoglobin, the protein in red blood cells responsible for carrying oxygen throughout your body. Without sufficient iron, you risk developing iron deficiency anemia, characterized by fatigue, weakness, and increased susceptibility to illness. Ensuring adequate iron intake through your diet is crucial for overall health, especially for infants and children as it supports their growth, brain development, and immune function.
Identifying Iron-Rich Foods
Many foods naturally contain iron, making it relatively easy to incorporate this essential mineral into your diet. These iron-rich foods can be categorized as follows:
- Animal Products: Meat, poultry (like chicken and turkey), fish (such as tuna and salmon), and eggs are excellent sources of iron.
- Legumes: Beans, peas, lentils, and tofu are plant-based options rich in iron.
- Grains: Whole grains like quinoa, oats, and whole-grain bread contribute to your iron intake.
- Vegetables: Dark green leafy vegetables, including spinach and beet greens, are known for their iron content.
- Nuts and Seeds: Nuts and seeds provide a source of iron.
Additionally, many processed foods are fortified with iron. In countries like Canada, the addition of iron to certain staples like white flour and meat substitutes is mandatory. Breakfast cereals, infant cereals, and pasta products may also have added iron. Checking the ingredient list on packaged foods will confirm whether iron has been added.
Heme vs. Non-Heme Iron: Understanding the Difference
The iron found in food exists in two primary forms: heme and non-heme iron.
- Heme Iron: This type is highly bioavailable, meaning it’s easily absorbed by the body. Heme iron is exclusively found in animal products, specifically meat, fish, and poultry.
- Non-Heme Iron: Non-heme iron is less readily absorbed compared to heme iron. It’s present in eggs, plant-based foods, and iron-fortified foods.
To enhance the absorption of non-heme iron, consume it alongside heme iron sources or foods rich in vitamin C. Vitamin C enhances iron absorption. Examples of foods high in vitamin C include red, yellow, and green peppers, broccoli, Brussels sprouts, snow peas, papaya, kiwi fruit, strawberries, oranges, and grapefruit.
Quantifying Iron Content in Foods
To determine Which Food Contains More Iron, refer to nutrition data or food labels. The Canadian Nutrient File is a useful resource for looking up the iron content of specific foods.
For packaged foods, consult the nutrition facts table. The % Daily Value (% DV) for iron indicates whether a food provides “a little” or “a lot” of iron. Generally, 5% DV or less signifies “a little,” while 15% DV or more is considered “a lot.” The label will also specify the amount of iron in milligrams (mg).
Food Sources of Iron: A Detailed Table
The table below provides a comprehensive overview of various food sources and their corresponding iron content:
| Foods with heme iron | Serving | Iron (mg) |
|---|---|---|
| Liver (pork, chicken, or beef)* | 75 g (2 ½ oz) | 4.6 to 13.4 |
| Oysters** or mussels | 75 g (2 ½ oz) | 5.0 to 6.3 |
| Lamb or beef | 75 g (2 ½ oz) | 1.5 to 2.4 |
| Clams | 75 g (2 ½ oz) | 2.1 |
| Sardines, canned | 75 g (2 ½ oz) | 2.0 |
| Tuna, herring, trout, or mackerel | 75 g (2 ½ oz) | 1.2 |
| Chicken or pork | 75 g (2 ½ oz) | 0.9 |
| Salmon or turkey | 75 g (2 ½ oz) | 0.5 |
| Foods with non-heme iron | Serving | Iron (mg) |
| Infant cereal with added iron | 28 g (5 tbsp) | 7.0 |
| Soybeans, cooked | 175 mL (3/4 cup) | 6.5 |
| Beans or lentils | 175 mL (3/4 cup) | 3.3 to 4.9 |
| Pumpkin seeds/kernels, roasted | 60 mL (1/4 cup) | 4.7 |
| Cold cereal with added iron | 30 g | 4.5 |
| Blackstrap molasses | 15 mL (1 tbsp) | 3.6 |
| Hot cereal with added iron | 175 mL (3/4 cup) | 3.4 |
| Spinach, cooked | 125 mL (1/2 cup) | 3.4 |
| Meatless meatballs | 150 g | 3.2 |
| Tofu, firm or extra firm, or edamame, cooked | 150 g (3/4 cup) | 2.4 |
| Tahini (sesame seed butter) | 30 mL (2 tbsp) | 2.3 |
| Chickpeas | 175 mL (3/4 cup) | 2.2 |
| Swiss chard or beet greens, cooked | 125 mL (1/2 cup) | 1.5 to 2.1 |
| Potato, baked with skin | 1 medium | 1.9 |
| Bagel | ½ bagel | 1.9 |
| Seaweed, agar (dried) | 8 g (1/2 cup) | 1.7 |
| Prune puree | 60 mL (1/4 cup) | 1.7 |
| Quinoa, cooked | 125 mL (1/2 cup) | 1.5 |
| Eggs | 2 | 1.4 |
| Quick or large flake oats, prepared | 175 mL (3/4 cup) | 1.4 |
| Almonds, walnuts, or pecans | 60 mL (1/4 cup) | 0.8 to 1.3 |
| Green peas, cooked | 125 mL (1/2 cup) | 1.3 |
| White bread | 35 g (1 slice) | 1.3 |
| Egg noodles with added iron | 125 mL (1/2 cup) | 1.2 |
| Sunflower seeds/ kernels, dry roasted | 60 mL (1/4 cup) | 1.2 |
| Tomato sauce, canned | 125 mL (1/2 cup) | 1.2 |
| Sauerkraut | 125 mL (1/2 cup) | 1.1 |
| Soy beverage | 250 mL (1 cup) | 1.1 |
| Spinach, raw | 250 mL (1 cup) | 0.9 |
| Dried apricots or raisins | 60 mL (1/4 cup) | 0.7 to 0.9 |
| Whole wheat bread | 35 g (1 slice) | 0.9 |
| Whole wheat pasta, cooked | 125 mL (1/2 cup) | 0.8 |
| Asparagus or sliced beets, cooked | 6 spears | 0.7 to 0.8 |
g = gram, mg = milligram, mL = milliliter, tbsp = tablespoon
Source: Canadian Nutrient File
*If you are pregnant, limit liver and liver products to 75g (2 ½ ounces) per week during the first trimester. Liver is high in vitamin A. Too much vitamin A may cause birth defects.
**Pacific oysters from British Columbia tend to be higher in cadmium. Limit intake to 12 per month for adults and 1.5 per month for children.
Optimizing Iron Intake for a Healthier You
Incorporating iron-rich foods into your diet is a proactive step towards maintaining optimal health. Understanding the difference between heme and non-heme iron and strategically combining foods to enhance absorption is key. By making informed food choices, you can effectively prevent iron deficiency and ensure your body receives the iron it needs to thrive.
