Iron (Fe++)

Functions

  • oxygen transport in red blood cells
  • production of hemoglobin and myoglobin
    • structures that enable oxygen to be carried in blood and stored in muscles
  • enzyme function
  • important for brain development
  • assists thyroid hormone synthesis via heme-dependent thyroid peroxidase (Zimmermann 2002)

Deficiency

  • anemia, fatigue, weakness
  • headaches
  • shortness of breath
  • iron deficiency anemia
  • dry coarse hair
  • hair loss
  • dysphagia
  • dizziness
  • slowed mental response
  • cracked lips or tongue
  • nervousness
  • pallor

Characteristic

  • Trace Mineral

Good Sources

Iron

Natural

  • red meat
  • liver, kidney
  • shellfish
  • egg yolks
  • beans
  • green leafy vegetables
  • apricots
  • whole grains
Food Quantity mg
Bread, whole wheat 1 slice 1.0
Eggs, scrambled 3 medium 2.2
Beef, sirloin, broiled 3 oz 2.6
Liver, fried 3 oz 5.3
Oatmeal, instant 1 packet 6.7

Artificial

  • acidic foods prepared in cast-iron pots
  • molasses

Recommended Daily Allowances (RDA)

  • Males
    • Adult
      • 8 mg
    • 19 years and older
      • 12 mg
    • 11-18 years
      • 10 mg
  • Females
    • Adult
      • 18 mg
    • 11-50 yrs.
      • 15 mg
    • 50+ yrs.
      • 10 mg
  • Pregnant females
    • 30 mg
  • Lactating females
    • 15 mg
    • 18 mg
  • Children (1-10 yrs)
    • 10 mg
  • Infants
    • 7 mths-1 yr
      • 10 mg
    • birth-6 mth
      • 6 mg
  • Varied values reflect different references

Tolerable Upper Intake Levels (UL)

  • Adults (19 to 50 yrs)
    • 45 mg
  • Intakes above 75 mg daily may lead to negative health consequences.
    • Abdominal cramping, vomiting, and diarrhea
    • Large doses may damage the heart, however liver and pancreas
    • Severe overdoses can be fatal if medical attention is not sought 

Well over 100,000 cases of accidental overdose of iron pills in children under 6 have been reported in the USA. Ingestion of as few as five tablets/200mg can result to death in children. Immediate medical attention is required for any possible incident overdose. Iron poisoning can also be harmful to adults.

Supplementation

  • Sometimes advised for dieters, strict vegetarians, and pregnant women.
  • Some recommend 15-25 mg daily for men and 18-30 mg for women
  • Iron supplements (38-65 mg/day) but not dietary levels of iron may decrease zinc absorption
  • Not required to be taken with other nutrients
    • However, vitamin C assists with iron absorption.
    • Coffee and tea can inhibit iron absorption.

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