Iodine: Why It Is Important And How To Get It In Your Diet?

Iodine Facts

Iodine An Important Micronutrient
Iodine An Important Micronutrient

Iodine, discovered in 1811, is a trace element and an essential micronutrient. (1) Approximately 80 percent of the body’s iodine content is found in the thyroid gland, where its sole purpose is to form a significant portion of two important hormones that greatly affect the body’s rate of metabolism and regulate normal growth and development. While the total quality of iodine needed in an entire lifetime is little more than a teaspoon, iodine cannot be stored and must be ingested regularly to support thyroid hormone production. Because very small amount of iodine are needed on a regular basis to prevent irreversible conditions caused by iodine deficiency, table salt is iodized to help supplement dietary intake.* (2)

Iodine is absorbed in both organic and inorganic forms by the body in the stomach and first portion of the small intestine. (93) Sufficient amounts of dietary iodine can be found in:

  • water
  • Oysters
  • fish (especially cod and cod liver oil, halibut, salmon, and trout)
  • beef and pork
  • eggs
  • spinach, cabbage, carrots, lettuce, peas, potatoes, tomatoes
  • bread
  • butter, cheese, and milk
  • apples and cranberries

While iodine is known at present to perform the single function of forming the two thyroid hormones thyroxine and triiodothyronine, iodine insufficiency can trigger many serious (some irreversible) disease states and conditions when the production of these hormones becomes compromised. The National Research Council recommends that adults may require slightly higher amounts of iodine in their diets. (4) A normal, well balanced diet will satisfy the body’s iodine requirements.*

Increases Endocrine Efficiency

The thyroid hormones comprised in part by iodine atoms, boost the rate at which the body’s cells use oxygen and organic molecules to produce energy and heat. They also improve cardiovascular activity by causing the vascular system to become more sensitive to nerve impulses, thereby facilitating increased cardiac output and heart rate appropriate to the situation. The thyroid hormones directly affect the maturing and day-to-day well being of both the skeletal and central nervous systems. They stimulate many different kinds of cells to perform their appropriate tasks, including protein synthesis. These hormones pay a key role in human growth rate, water balance, and numerous physiological processes.* (5)

Reduces the Incidence of Physical and Mental Retardation Caused by Iodine Deficiency Disorders

The thyroid hormone thyroxine contains four atoms of iodine per molecule and is vital to the normal growth and development – both physically and mentally – of all young animals and humans. If a child has an iodine deficiency disorder and the thyroid gland fails to produce or secrete sufficient amount of thyroxine, he or she could suffer varying forms of cretinism (arrested physical and mental development). These children can grow stunted physically, and appear sluggish, mentally retarded, or even unable to move normally, speak, or hear.* (4)

Improves Reproductive Capability

For many years, animals raised in low-iodine regions showed increased sterility. In these same areas of the country where the iodine content in the soil is low, young animals were born with different skeletal deformities and limitations. The numbers of these reproductive problems decreased significantly with iodine supplementation. Likewise, some women developed goiters during their pregnancies, pointing to greater need for the thyroid hormones during this period.*

Reduces the Incidence of Endemic Goiter Development

An endemic goiter is an enlargement of the thyroid gland caused by inadequate iodine intake. It can range in size anywhere from an invisible but palpable nodule all the way up to the size of a large male fist. (6). The size of the goiter is proportional to the amount of iodine deficiency. While goiters are mainly a problem only in developing countries at this time, they can still be seen in some parts of Europe. Goiters are not major medical problems, unless they become large enough to compress the airway or esophagus.*

  1. Mosby’s Medical, Nursing & Allied Health Dictionary, 5th Edition. Mosby – Year Book Inc. 1998. p. 871
  2. Human Physiology and Mechanisms of disease. Sixth Edition. Guyton, Arthur C. MD; Hall, John E Ph.D. 1997. W.B. Saunders Co. pps 607-614
  3. the Nutrition and Health Encyclopedia. Second Edition. Russell, Percy Ph.D.; Tver, David F. 1989. Van Nostrand Reinhold, New York, p 284
  4. Principles of Nutrition. Second Edition. Wilson, Eva D. et al. 1965. John Wiley and Sons Inc. New York. Pp 165-77
  5. Human anatomy and Physiology. Third Edition. Carola, Robert, et al. 1995. McGraw-Hill, Inc. p 559
  6. Modern Nutrition in Health and Disease. Seventh Edition. Shils, Maurice E. MD, Sc.D; Young, Vernon R. Ph.D. 1988. Lea & Febiger. pps 227-36
  7. McDowell, L., Parkey, D. Iodine deficiencies result in need for supplementation. Journal: Feedstuffs. Carol Stream IL. Miller Publishing co. October 9, 1995. V. 67(42);p15, 18
  8. Delange, F. Iodine deficiency in Europe. Cas Lek Cesk. 1995. Jan 18;135(2):35-43
  9. Hetzel, B.S. the iodine deficiency disorders. Journal: NATO-ASI-Ser-ser-A-Life-Sci. New York, Plenum Press. 1993. V. 241:pps 25-31
  10. Delange, F. Screening for congenital hypothyroidism used as an indictor of the degree of iodine deficiency and of its control. Thyroid. 1998. Dec;8(12):1185-92
  11. Delange, F. , Nicorandil: The disorder induced by iodine deficiency. Thyroid 1994. Spring;4(1):107-28
  12. Pennington, J.A.T. Iodine. Journal: Trace minerals in foods. Edited by Kenneth T. Smith. New York: M. Dekker. C1988. pps. 249-89
  13. Delange, F. Requirements of iodine in humans. Journal: NATO-ASI-Ser-ser-A-Life-Sci. New York, NY. Plenum Press. 1993. Vol 241:pps 5-15.

*The statements have not been evaluated by the Food & Drug Administration.

Calcium and Magnesium: All You Need To know

Calcium is an alkaline earth metal element and the fifth most plentiful element in the human body, residing mainly in the bones. The body needs calcium ions to:

  • Transmit nerve impulses
  • Contract muscles
  • Clot blood
  • Carry out certain cardiac functions, and
  • Facilitate a number of other physiological processes

Calcium builds strong bones and teeth. It is also part of the extracellular fluid and soft tissue cells. (1)

While dairy products provide the greatest sources of calcium for many people, it can also be found in leafy green vegetables. However, it’s important to avoid those vegetables containing oxalic acid, since it compromises calcium absorption. Broccoli provides the best source of vegetable derived calcium. Citrus fruits, egg yolks, and legumes contain a fair amount of dietary calcium, while meats, grains, and nuts contain only modest amounts. (2)

Daily optimal amounts of calcium are affected by gender, age, protein, and vitamin D intake. People require different amounts of calcium at different stages of their life, and vast amounts of calcium can be lost in the urine when large amounts of protein are ingested. Vitamin D also plays a role in calcium absorption. Based on an absorption rate of about 40% and an average daily loss of approximately 320 milligrams: children between the ages of six months and a year require 540 milligrams; children between the ages of 11-18 require 1,000 milligrams per day, and adult men and women require 800 milligrams daily. Pregnant, lactating, and postmenopausal women not on estrogen supplementation require 1,200 milligrams of calcium per day. (3) It is estimated that stone-age, adults took in three to five times as much calcium as today’s adults living in the United States. (15)

Magnesium is a mineral element found in nature and is always combined with other elements. It is the second most abundant “cation” (positively charged ion) found in the intracellular fluids in the body. Magnesium is fundamental for multiple enzyme activities and in the interaction of intracellular particles. Similar to and working with calcium, magnesium is material in neurochemical transmission and for initialing muscular movement. Magnesium affects the central nervous, neuromuscular, and cardiovascular systems. (1)

Magnesium can be found in both plant and animal sources. Meats, milk, and cereal grains contain the greatest amount of magnesium. Vegetables – including potatoes – flour, eggs, coffee, cocoa, dry beans, nuts, and legumes also contain some of this important mineral. (4) The daily recommended allowance for magnesium is 350 milligrams, and like many other vital nutrients, it is feared that many people fail to get adequate amounts consistently through their diet. (5)

  • Builds Strong Bones and Teeth

    The human body contains more calcium than any other mineral.(6) It is essential in keeping bones and teeth at the proper density to sustain daily wear and tear. While almost 90 percent of the body’s calcium resides in the bones and teeth, it is also circulating in fluids and soft tissues. Bone stability is maintained by the ongoing activities of bone formation and resorption.(4) During the first 20 years of life, growing bones keep pace with calcium accumulation. But somewhere during the next decade of life, the gentle balance changes, and the bones begin to lose precious calcium in varying degrees. Between the ages of 30 and 50, bone mass density begins a gradual, almost unappreciable decline. After the age of 50, bone mass density loss accelerates, especially in menopausal women.(7) In almost every study conducted to examine the role of calcium in bone loss, patients who took in adequate amounts of calcium showed a decrease in bone loss and suffered fewer fractures over time.(8) Calcium is the primary treatment used today to prevent and treat osteoporosis.

    Magnesium joins calcium in helping to keep the skeletal system healthy, but in a vastly different capacity. Playing a key role in at least 300 enzymatic reactions for intermediary metabolism, 60% of the body’s magnesium is found in the bones, while the rest is located within the cells of soft tissue.(4) One clinical trail substituted a dietary program rich in magnesium instead of calcium for postmenopausal women on hormonal therapy. Bone mineral density increased drastically in most of the women over the first year. (9)

  • Keeps The Heart Healthy

    In order for the heart muscle to contract normally and maintain a regular beat, the tissue fluid that washes the muscle must contain an adequate amount of calcium. (2) Likewise, magnesium plays an important role in regulating heartbeats by its ability to support the heart muscle in the relaxation phase. Magnesium salts have been used for over 50 years to treat irregular heartbeats caused by a number of different diagnoses. (4) Both calcium and magnesium have been used as part of treatment for congestive heart failure (CHF). These two important elements share great responsibility for supporting normal heart rhythms.

  • Maintains Cellular Efficiency

    Calcium and magnesium join forces at the cellular level to maintain normal cell growth and replication. Calcium is a chief factor for the normal clotting of blood. Calcium works with phosphorus at the cellular level reacting with proteins, fats, and carbohydrates to supply energy and the materials for growth and repair. (4) Magnesium is involved in the synthesis and reduction of DNA, as well as many other metabolic processes at the cellular level. Calcium and magnesium work together to promote normal responses from nerves to different types of stimulation. (4)

    • Mosby’s Medical, Nursing, & Allied Health Dictionary, 5th Edition, Mosby, St. Louis. 1998
    • Wilson, E. et al. Principles of Nutrition. 2nd Edition, John Wiley & Sons, Inc. 1965. pps 134-50
    • Tver, David F. & Russell, Percy, Ph.D. 2nd Edition. Van Nostrand Reinhold. 1989. pps 86, 312
    • Shils, Maurice E., M.D., Sc.D & young, Vernon R. Ph.D. Modern Nutrition in Health and Disease. 7th Edition. Lea & Febiger, 1988. pps 142-188, 1566
    • Schachter, Michael, M.D., FACAM. The Importance of magnesium to human nutrition. 1996. HealthWorld Online
    • Haas, Elson M. M.D. Minerals, 1999. HealthWorld Online
    • Bronner, Felix, Nutrition and Health, Topics and Controversies. CRC Press. 1995. pps 114-121
    • Blythe, Stephan, D.O. Nutritionist, Dietary Calcium to Prevent Osteoporosis. Brevard Health Online
    • Abraham, G.E. & Grewal, H. A total dietary program emphasizing magnesium instead of calcium. Effect on the mineral density of calcaneous bone in postmenopausal women on hormonal therapy. Journal of Reproductive Medicine. 1990. May;35(5):503-7
    • Guyton, Arthur C., & Hall, John E. Ph.D. Human physiology and Mechanisms of Disease. 6th Edition. W.B. Saunders Company
    • Van Wynsberghe, Donna. Human Anatomy and Physiology. McGraw-Hill, Inc. 1995. pps 598, 927
    • Whitfield, James, F. Calcium, Cell Cycles, and Cancer. CRC Press Inc. 1990, pps 183-184
    • Willett, Walter. M.D. Nutritional epidemiology. Oxford University Press. 1990. pps 183-184
    • Seelig, M. Cardiovascular consequences of magnesium deficiency and loss; pathogenesis, prevalence and manifestations – magnesium and chloride loss in refractory potassium repletion. American Journal of Cardiology. 1989 Apr 18:6(14):4G-21G
    • Barger-Lux, J.D. & Heaney, R.P. the role of calcium intake in preventing bone fragility, hypertension, and certain cancers. Nutrition Journal. 1994. Aug;124(8 suppl):1406S-1411S
    • Northover, B.J. et al. the involvement of lactate and calcium as mediators of the electrical and mechanical responses of the myocardium to conditions of simulated ischaemia. British Journal of Pharmacology. 1989. July;97(3):809-18
    • Moon, J. et al. Hypothesis: Etiology of atherosclerosis and osteoporosis. Are imbalances in the calcified endocrine system implicated? Journal of the American College of Nutrition. Oct 1992. V 11(5) pps 567-583

    *None of the statements on the information sheet have been evaluated by the Food & Drug Association.