Iron is a very tricky mineral. Too much of it creates toxicity within the body, but too little can lead to anemia.
Essentially, the majority of iron already in our bodies exists within the hemoglobin - the protein of our red blood cells. It helps transport oxygen to tissues and assists in cellular growth. Iron also exists within enzymes and aids in food digestion.
There are two types of food iron: heme and non-heme. Meat sources provide 40% heme iron and 60% non-heme iron. Heme iron is derived from hemoglobin, and is therefore found in animal sources but not in plant sources. Vegan and vegetarian diets are completely without heme iron sources, but this does not automatically equate to an iron deficiency. In fact, studies have shown that those on plant-based diets are at no greater risk of developing iron deficiency than omnivores.
The CDC lists Recommended Daily Values for iron at 15-18 mg/day for teens and women up to menopause, and 8 mg/day post-menopause. Women require so much additional iron before menopause to recoup for mineral loss during menstruation. Men, other than teens between 14-18, require an average of 8 mg/day throughout their lives.
In addition, vegans and vegetarians should give themselves a nice buffer around that average and aim for approximately twice the RDV to compensate for the lack of heme iron.
The Vegetarian Resource Group provides a great list of non-heme iron sources:
|Blackstrap molasses||2 Tbsp||7.2|
|Lentils, cooked||1 cup||6.6|
|Spinach, cooked||1 cup||6.4|
|Bagel, enriched||1 medium||6.4|
|Chickpeas, cooked||1 cup||4.7|
|Lima beans, cooked||1 cup||4.5|
|Black-eyed peas, cooked||1 cup||4.3|
|Swiss chard, cooked||1 cup||4.0|
|Kidney beans, cooked||1 cup||3.9|
|Black beans, cooked||1 cup||3.6|
|Pinto beans, cooked||1 cup||3.6|
|Turnip greens, cooked||1 cup||3.2|
|Prune juice||8 ounces||3.0|
|Quinoa, cooked||1 cup||2.8|
|Beet greens, cooked||1 cup||2.7|
|Veggie hot dog, iron-fortified||1 hot dog||2.7|
|Peas, cooked||1 cup||2.5|
|Bok choy, cooked||1 cup||1.8|
|Bulgur, cooked||1 cup||1.7|
|Apricots, dried||15 halves||1.4|
|Veggie burger, commercial||1 patty||1.4|
|Kale, cooked||1 cup||1.2|
|Sunflower seeds||1/4 cup||1.2|
|Broccoli, cooked||1 cup||1.1|
|Millet, cooked||1 cup||1.1|
|Soy yogurt||6 ounces||1.1|
|Tomato juice||8 ounces||1.0|
|Sesame seeds||2 Tbsp||1.0|
|Brussels sprouts, cooked||1 cup||0.9|
There are two main reasons vegetarians and vegans often don't have low iron levels:
1. their diets tend to include foods with much higher iron contents
For comparison's sake - 100 calories of roasted chicken breast has only 0.6 mg of iron, whereas 4 ounces of tofu contains 6.4 mg of iron.
2. their diets are also generally higher in vitamin C, which greatly increases the absorption of non-heme iron into the body
Red and green peppers, kiwis, canteloupe, papaya, guava, strawberries, mangoes and pineapple, cauliflower, pea pods, sweet potatoes and Brussels sprouts are all high in vitamin C.
There are even a few foods like broccoli and kale that provide great levels of both iron and vitamin C in one delicious little package!
Simple combinations like baked tofu and broccoli, or raw peppers and cauliflower with chickpea hummus are easy ways to keep your body well-stocked in both non-heme iron and vitamin C.
A final word about iron supplements...
If you're feeling weak, tired, unable to concentrate or constantly cold, talk to your primary care physician and before jumping on the iron supplement ship. A doctor can perform necessary blood tests to assess your current iron levels, and help you determine the best way to increase your iron stores.