I Run on Iron

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Introduction
Iron is a micronutrient that we’ve all probably heard of, but don’t know what it actually does. Sure, everyone knows that Popeye loves his spinach, but what does iron actually do, and what are some good sources of it?

Role of Iron
Iron is an essential micronutrient, meaning that your body does not produce it. Rather, it must be obtained from food or supplementation. The Recomended Daily Value (RDA) of iron is 8 mg for men and 18 mg for women. If you’re pregnant, then the RDA increases to 27 mg. It is one of the few micronutrients required to be on a food label, making it easy to track.

The main function of iron is for oxygen transportation. This is done by the production of heme to make hemoglobin, a protein found in red blood cells that carries oxygen from your lungs throughout your entire body. Oxygen plays a vital role in cellular function and the production of Adenosine Triphosphate (ATP), the body’s main source of energy (it is often referred to as the “energy currency”)

Symptoms of Low Iron
Iron deficiency is one of the more common nutrient deficiencies, particularly impacting children and women. Lack of iron in the body leads to a lack of hemoglobin production, impacting all cells in your body. Also known as sideropenia, iron deficiency impacts about 10% of men and 35% of women. Other potential causes of iron deficiency could be low protein, vitamin B12, vitamin A, or folate.

Common symptoms of iron deficiency anemia include:

Fatigue
Weakness
Headache
Brain fog
Rapid heart rate
Trouble breathing
Impaired immune system
Irritability
Pale skin
Brittle nails
Hair loss

Optimal Ranges for Men

Ferritin: 15-300 ng/mL
Total Iron Binding Capacity (TIBC): 250-450 mcg/dL
Iron: 50-195 mcg/dL (ages 20-29) or 50-180 mcg/dL (ages 30+)
Iron % Saturation: 20-48%
Hemoglobin: 11.10-15.90 g/dL
Red Blood Cell (RBC) Count: 3.77-5.28 cells/mcL
Hematocrit: 34.0-46.6 %

Optimal Ranges for Women

Ferritin: 15-150 ng/mL
Total Iron Binding Capacity (TIBC): 250-450 mcg/dL
Iron: 40-190 mcg/dL (ages 20-49) or 45-160 mcg/dL (ages 50+)
Iron % Saturation: 20-48%
Hemoglobin: 11.10-15.90 g/dL
Red Blood Cell (RBC) Count: 3.80-5.19 cells/mcL
Hematocrit: 34.0-46.6 %

Foods High in Iron
Iron is found in both animal based (heme) and plant based (non-heme) foods; however, heme iron (found in animal products) is much more bioavailable than non-heme iron (found in plant based products). Since non-heme iron is not absorbed as well by the body, you may need to consume at least double the recommended amounts of iron if you do not consume meat. For reference, heme iron has an absorption rate of about 15-35%, whereas non-heme iron has an absorption rate of about 2-20%. However, the absorption rate of non-heme iron is improved when consumed with heme-iron.

The following tables list foods by their content of iron per serving, per 100 g, and per 100 calories, sorted alphabetically. Each food is raw, unless otherwise specified.

Meat (raw)

Food	Serving Size	Iron Per Serving	Iron Per 100 g	Iron Per 100 cal
Chicken breast (boneless and skinless)	4 oz (113 g)	0.4 mg	0.4 mg	0.3 mg
Chicken thighs (boneless and skinless)	4 oz (113 g)	1.1 mg	1.0 mg	0.8 mg
Eggs	1 egg (50 g)	0.8 mg	1.7 mg	1.1 mg
Ground beef (93% lean)	4 oz (113 g)	2.6 mg	2.3 mg	1.5 mg
Ground turkey (93% lean)	4 oz (113 g)	1.3 mg	1.2 mg	0.8 mg

Fish and Seafood (raw unless specified)

Food	Serving Size	Iron Per Serving	Iron Per 100 g	Iron Per 100 cal
Anchovies (canned)	2 oz can, drained	2.1 mg	4.6 mg	2.2 mg
Clams (canned)	2 oz (55 g)	1.0 mg	1.8 mg	1.7 mg
Mackerel (canned)	1/2 cup, drained (85 g)	1.5 mg	1.8 mg	1.3 mg
Mussels	1 large mussel (20 g)	0.8 mg	4.0 mg	4.7 mg
Oysters	1 oyster (14 g)	0.7 mg	4.6 mg	9.9 mg
Salmon	3 oz (85 g)	0.7 g	0.8 mg	0.6 mg
Sardines (canned)	3.75 oz can, drained	1.9 mg	2.3 mg	1.2 mg
Scallops	3 oz (85 g)	0.3 mg	0.4 mg	0.5 mg
Shrimp	4 oz (113 g)	0.2 mg	0.2 mg	0.3 mg
Tilapia	4 oz (113 g)	0.7 mg	0.6 mg	0.6 mg
Tuna (canned)	5 oz can, drained	2.7 mg	1.6 mg	1.9 mg

Beans and Lentils (dried unless specified)

Food	Serving Size	Iron Per Serving	Iron Per 100 g	Iron Per 100 cal
Black beans	1/4 cup (48 g)	2.4 mg	5.0 mg	1.5 mg
Chickpeas	1/4 cup (50 g)	2.2 mg	4.3 mg	1.1 mg
Edemame (frozen)	3/4 cup (85 g)	1.8 mg	2.1 mg	1.9 mg
Green lentils	1/4 cup (50 g)	4.0 mg	8.0 mg	2.2 mg
Kidney beans	1/4 cup (46 g)	3.1 mg	6.7 mg	2.0 mg
Navy beans	1/4 cup (52 g)	2.9 mg	5.5 mg	1.6 mg
Pinto beans	1/4 cup (57 g)	2.5 mg	5.1 mg	1.5 mg
Red Lentils	1/4 cup (50 g)	3.7 mg	7.4 mg	2.1 mg
Tofu	1/2 cup (122 g)	3.4 mg	2.8 mg	1.9 mg

Vegetables (raw)

Food	Serving Size	Iron Per Serving	Iron Per 100 g	Iron Per 100 cal
Broccoli	1 cup (91 g)	0.7 mg	0.7 mg	2.3 mg
Chard	1 cup (36 g)	0.7 mg	1.8 mg	10.3 mg
Kale	1 cup (21 g)	0.3 mg	1.6 mg	4.1 mg
Potaotes	1 potato (170 g)	1.4 mg	0.8 mg	1.1 mg
Spinach	1 cup (30 g)	0.8 mg	2.7 mg	11.6 mg
Sweet potatoes	1 sweet potato (130 g)	0.8 mg	0.6 mg	0.7 mg

Fruit

Food	Serving Size	Iron Per Serving	Iron Per 100 g	Iron Per 100 cal
Dates	6 Deglet Noor or 2 Medjool (40 g)	0.4 mg	1.0 mg	0.4 mg
Dried Figs	1/4 cup (42 g)	0.9 mg	2.0 mg	0.9 mg
Raisins	1/4 cup (40 g)	0.7 mg	1.8 mg	0.6 mg
Strawberries	1 cup (144 g)	0.6 mg	0.4 mg	1.3 mg
Watermelon	1 cup (152 g)	0.4 mg	0.2 mg	0.9 mg

Nuts and Seeds (raw)

Food	Serving Size	Iron Per Serving	Iron Per 100 g	Iron Per 100 cal
Almonds	1 oz (28 g)	1.0 mg	3.6 mg	0.6 mg
Cashews	1 oz (28 g)	1.7 mg	6.0 mg	1.1 mg
Chia seeds	1 oz (28 g)	2.2 mg	7.7 mg	1.6 mg
Flaxseeds	1 oz (28 g)	1.6 mg	5.7 mg	1.1 mg
Hazelnuts	1 oz (28 g)	1.3 mg	4.7 mg	0.7 mg
Hemp Seeds	1 oz (28 g)	3.4 mg	12.0 mg	2.0 mg
Macadamia nuts	1 oz (28 g)	1.1 mg	3.7 mg	0.5 mg
Peanuts	1 oz (28 g)	1.3 mg	4.6 mg	0.8 mg
Pecans	1 oz (28 g)	0.7 mg	2.6 mg	0.4 mg
Pine nuts	1 oz (28 g)	1.6 mg	5.5 mg	0.8 mg
Pistachios	1 oz (28 g)	1.1 mg	3.9 mg	0.7 mg
Pumpkin seeds	1 oz (28 g)	4.3 mg	15.0 mg	2.8 mg
Sesame seeds	1 oz (28 g)	4.1 mg	15.0 mg	2.5 mg
Walnuts	1 oz (28 g)	0.7 mg	2.6 mg	0.4 mg

Grains (raw)

Food	Serving Size	Iron Per Serving	Iron Per 100 g	Iron Per 100 cal
Brown Rice	1/4 cup (46 g)	0.6 mg	1.3 mg	0.4 mg
Quick oats	1/2 cup (40 g)	1.7 mg	4.3 mg	1.1 mg
Quinoa	1/4 cup (43 g)	2.0 mg	4.6 mg	1.3 mg
Whole wheat flour	1/4 cup (30 g)	1.1 mg	3.6 mg	1.1 mg
Vital Wheat Gluten	1/4 cup (30 g)	1.8 mg	6.0 mg	1.5 mg

Other

Food	Serving Size	Iron Per Serving	Iron Per 100 g	Iron Per 100 cal
100% chocolate	1 square (14 g)	2.4 mg	17.0 mg	2.7 mg
Cocoa powder	1 tbsp (5 g)	0.8 mg	14.0 mg	6.7 mg

Best Sources of Iron (Animals)
Per serving: Ground Beef (93% lean) - 2.6 mg (4 oz, 113 g)
Per 100 g: Oysters - 4.6 mg
Per 100 cal: Oysters - 9.9 mg

Best Sources of Iron (Plants)
Per serving: Pumpkin seeds - 4.3 mg (1 oz, 28 g)
Per 100 g: 100% chocolate - 17.0 mg
Per 100 cal: Spinach - 11.6 mg

Other Ways to Consume Iron
Sometimes, eating iron rich foods isn’t enough to raise your iron levels if you’re deficient. An iron deficiency might also signal that you are low in vitamin C, as vitamin C aids in the absorption of iron. Try to eat more naturally occuring sources of vitamin C, such as the following:

Citrus fruits: grapefruit, lemon, orange, and kiwi
Berries: Strawberries, raspberries, blackberries, and blueberries
Cruciferous vegetables: Broccoli, cauliflower, kale, cabbage, and brussel sprouts
Other vegetables: Bell peppers, spinach, and tomatoes

If you are unable to raise your iron or ferritin through food alone, it may be helpful to take an iron supplement. Vitamin C supplementation may also be useful, but consult with your doctor before making any changes.

Iron: 60-330 mg daily
Vitamin C: 250-500 mg daily

Sources