Minerals work throughout the body to regulate processes and provide structure. Iron while an essential trace mineral, is not widely talked about. Because it can frequently be low and zap your energy, let's take a closer look at this essential nutrient.



What is it?

Iron is an abundant metal necessary to help carry oxygen to all parts of the body as part of blood cells. It is also essential for cell growth regulation and mediation. Estimates suggest 60-65 percent of the iron in our body is part of hemoglobin. Another 30 percent is stored as ferritin in the liver, spleen, and bone marrow. A small portion of iron is found in transport. The amount of available iron is largely dependent on gender, body size, and blood volume with men having more iron than women do.

How much do I need?

Requirements per kilogram of body weight are highest during infancy since newborns have low iron stores at birth. They are also high in adolescents because of their rapid rate of growth. Menstruating women have a higher need than those that are non-menstruating and due to expanding blood volume, needs for women are highest during pregnancy. The Recommended Daily Allowance (RDA) for iron in infants is 11 mg/day while adolescent teens require up to 15 mg/day and pregnant women require a whopping 27 mg/day. Adult men and women over the age of 51 are encouraged to consume 8 mg of iron each day. Adult women between the ages of 19-50 should aim for 18 mg of iron each day. According to the Institutes of Medicine, vegetarian men and post-menopausal women need 14 mg daily and pre-menopause vegetarian women should aim for 33 mg each day.

Where do I find it?

There are two different types of iron. Heme iron comes from animal food sources and is two to three times more absorbable than non-heme iron from plant food sources. Heme sources of iron typically have an absorption rate of 15-35 percent with minimal influence from other foods in the diet. In comparison, non-heme iron sources have a 2-20 percent rate of absorption and are significantly influenced by other foods. This is an important point especially since intestinal absorption is the major control mechanism for iron.

Good heme sources of iron include:

Beef, lamb, veal – 2.5 mg per 3 ounce serving

Beef, chuck, lean – 3.2 mg per 3 ounce serving

Beef, lean ground: 10% fat – 3.9 mg per 3 ounce serving

Beef liver – 7.5 mg per 3 ounce serving

Beef tenderloin, roasted – 3.0 mg per 3 ounce serving

Chicken liver – 12.8 mg per 3.5 ounce serving

Boiled Shrimp – 2.6 mg per 3 ounce serving

Good non-heme sources of iron include:

Apricots, dried – 1.7 mg per 10 medium sizes fruits

Black beans, boiled – 3.6 mg per 1 cup serving

Cereal, ready-to-eat, 100% iron fortified – 18.0 mg per ¾ cup serving

Kidney beans, boiled – 5.2 mg per 1 cup serving

Lentils, boiled – 6.6 mg per 1 cup serving

Lima beans, boiled – 4.5 mg per 1 cup serving

Molasses, blackstrap – 3.5 mg per 1 tablespoon serving

Navy beans, boiled – 4.5 mg per 1 cup serving

Oatmeal, prepared instant fortified – 10 mg per 1 cup serving

Pinto beans, boiled – 3.6 mg per 1 cup serving

Spinach, fresh cooked – 6.42 mg per 1 cup serving

Tofu, raw, firm – 3.4 per ½ cup serving

Additional Considerations

Iron deficiency can gradually develop when intake and absorption does not meet daily needs by the body. Maximizing non-heme iron absorption is most important when daily intake is less than recommended, intake needs are high (during pregnancy and teen growth spurts), iron losses are high (during heavy menstruation) or when only non-heme sources are selected. Medical conditions also increase risks of anemia from iron deficiency. If you have kidney disease (especially those on dialysis) or gastrointestinal disorders (such as Celiac Disease or Crohn's Syndrome), please work with your medical team to monitor iron absorption and storage levels. People who follow dietary practices that exclude all animal products (vegan diet) are also at increased risks for iron deficiency.

Signs of iron deficiency anemia include:

• Persistent feelings of weakness and being tired
  
  
• Changing performance at work or school
  
  
• Body temperature irregularities
  
  
• Frequent infections or illnesses due to decreased immune responses
  
  
• Inflammation of the tongue
  
  
• Sudden and persistent interest in eating non-nutritive items such as dirt or chalk (condition called pica or geophagia)

Tips and Tricks

To increase iron absorption try these tips:

• Include a meat source of protein with plant food sources to increase plant iron absorption.
  
  
• Include foods that provide a good source of vitamin C in the same meal with plant iron food sources since vitamin C helps with non-heme iron absorption.
  
  
• Avoid coffee and tea with iron-rich foods since the tannins in the tea and coffee decrease iron absorption. Herbal teas such as chamomile, peppermint, lime flower, and pennyroyal should also be limited when maximum iron absorption is desired.
  
  
• Spinach, beet greens, rhubarb, and Swiss chard contain an oxalate acid that binds with iron and makes it unavailable for the body. Be sure you are not relying on these vegetables as your primary plant based iron source.
  
  
• Use a cast iron pot or skillet, especially with acidic foods for food preparation.
  
  
• If your medical provider has recommended an iron supplement, be sure you are taking it several hours before a meal containing coffee, tea, dairy products or calcium supplements as these can significantly decrease the amount of iron absorbed.

Do you have trouble getting enough iron in your diet? What are your favorite high iron foods?