Micronutrients
Written by Jeff Behar, MS, MBA

Many nutrition specialists refer to components of the diet, which are present in large amounts, as macronutrients. The macronutrients include carbohydrates, fats, and protein, all of which provide calories. Few Americans are deficient in calories or macronutrients; Micronutrient status is a different story however. The essentiality of micronutrients for human health was established many years ago. The prevention of deficiency disorders was the main driver for micronutrient research.
So what are micronutrients?

Micronutrients are nutrients that the body needs in minuscule amounts. Even though they are needed only in small amounts these substances are essential to life and enable the body to produce enzymes, hormones and other vital substances essential to the human body for proper growth and development. As tiny as the amounts are, however, the consequences of their absence are severe.



Causes of micronutrient deficiencies
Insufficient dietary intake, malabsorption, diarrhea, and impaired storage and altered metabolism of micronutrients can contribute to the development of micronutrient deficiencies.



Micronutrients are often lacking due to a poor diet, malabsorption (a poor ability to extract nutrients from the food, and/or a food supply), soil lacking in certain nutrients and altered metabolism of micronutrients can contribute to the development of micronutrient deficiencies. Micronutrients are important because they consist of a wide array of necessary substances that your body requires to keep all systems operating at peak efficiency.



Besides a poor diet there are other reasons why you could find your body deficient in certain micronutrients that can contribute to a disease or ailment, or at the least keep you from feeling your best. Many people suffer from a poor ability to extract nutrients out of the food they eat. This is often due to a lack of specific enzymes in the upper intestine, which allows the digestive system to break down the nutrients in the food into molecules that are small enough to pass through the membrane of the small intestine. Additionally due to modern farming practices, most staple foods today contain only a fraction of the nutrients the same foods used to have only fifty years ago. How people cook and process their foods can also contribute to micronutrient deficiencies.


The impact of micronutrient deficiencies worldwide

Recent changes in dietary patterns and lifestyle (increasing consumption of processed foods) in industrialized societies and the changing demographics of the population have provoked serious concern about the quality of the diet and its impact on health, including the supply of key micronutrients, for example iron and selenium.



The use of high-yielding cultivars that remove high amounts of micronutrients from the soil, lead to micronutrient deficiencies in many countries; especially poor developing countries. Because of poor diet, and nutrient deficient soils micronutrient deficiencies are becoming more and more widespread in developing countries. It is said to affect approximately 2 billion people worldwide (approximately one-third of the world's total population).



Among the micronutrients reported as becoming deficient worldwide, zinc and iron are the most important elements. In fact, it is estimated that more than 3 billion people worldwide suffer iron and zinc deficiencies, and this condition is widespread in areas whose populations rely heavily on an unvaried diet of cereal-based foods.



It is estimated that iron deficiency occurs in about 30% of cultivated soils worldwide, which is indicative of its low availability in calcareous high-pH soils, and that about 50% of the soils cultivated for cereal production have low levels of available Zinc.


The importance of micronutrients

How are these "wonder nutrients" important? Your organs require a broad range of nutrients in order to function properly and to keep the cells in your body supplied with all the chemicals and hormones they need. If any critical nutrients are missing or deficient, then breakdowns in cellular metabolism are sure to happen resulting in disease and accelerated aging. Most diseases are linked to nutrient deficiencies or imbalances. Micronutrients are also important for mental health. Certain micronutrients (the anti-oxidants) can help maintain the oxygen balance in your brain, as well as combat the highly-reactive forms of oxygen called free radicals. Antioxidant levels diminish with age, therefore the aging brain appears to be an easy target for oxidative damage.



Although the body is incredibly resilient and adaptive; and can "get by" in a weakened state for quite some time, the lack of micronutrients takes its toll on the body. This underscores the importance of getting enough micronutrient antioxidants through diet and supplements.



According to surveys done by the National Institutes of Health, most Americans obtain the required amounts of the most micronutrients, although that is not the case for many developing nation populations worldwide. However, even in developed countries there are certain micronutrients which tend to be more difficult to obtain in adequate amounts through a normal diet and are more likely to be found at deficient levels in many people. For example magnesium and vitamin B12 are micronutrients, which are found at low or deficient levels in many people, especially those over the age of 50. Adequate levels of vitamin D are also difficult for many people to obtain due to deficiencies and also due to the recent concern over exposure to the sun, which contributes to the development of Vitamin D from Vitamin A.



Some examples of micronutrients and their role in human health



B-12. Most people get enough quantities of it in our normal meals to satisfy our daily requirements. Although it's rare to see vitamin b12 deficiency symptoms it can still be useful to be able to recognize them just in case. The main symptom that arises from vitamin b12 deficiency is a type of anaemia that causes you to feel tired, weak and lethargic. You might also feel nauseous, constipated and become very flatulent (gas). You may also lose your appetite and suffer weight loss, or experience sleeplessness, and/or depression. B-12 defencies can also cause neurological issues, such as sensory disturbances due to damage to peripheral nerves caused by demyelination and irreversible nerve cell death. Symptoms include numbness, tingling of the extremities, disturbed coordination and, if not treated in time, an ataxic gait, a syndrome known as subacute combined degeneration of spinal cord. Recent research (Tuft’s University, 2000) indicates that B12 deficiency is far more widespread than formerly believed. Researchers at Tuft University found that in the US 39 percent of the study population had low values. greater proportion of the population than 39% as reported by the Tufts University. This issue is even more widespread in developing countries due to low intakes of animal products, B-12 deficiency is also very common in the elderly because B12 absorption decreases greatly in the presence of atrophic gastritis, which is common in elderly. There are also several studies that indicate that B12 deficiency is common among vegetarians, because of the lack of consumption of animal products. A 1982 study found blood levels below normal in 92 % of vegans, 64 % of lactovegetarians, 47 % of lacto-ovovegetarians, however more recent studies show the numbers may be lower, but still a significant issue which warrants the need to consider supplementation for these at risk populations. An adequate folic acid intake can actually mask a B12 deficiency. Since strict vegetarian diets often consist of green vegetables rich in folic acid it may be necessary to supplement their diets with cobalt and B-12 to prevent irreparable nerve damage that can be masked by a B12 deficiency.



Cobalt. Cobalt is required for biosynthesis of vitamin B12 family of coenzymes, helps with the repair of the myelin sheath, pernicious anemia, and the building of red blood cells. Cobalt also increases the body's ability to absorb and utilize vitamin B12. Deficiency of cobalt resulting in decreased cobalamin can also result in hormonal imbalance. Some enzymes are also stimulated by the interaction of cobalt. Cobalt and vitamin B12 work together in the human body in the form of cobalamin. Because an adequate folic acid intake can actually mask b-12/cobalt deficiency it is important to monitor your diet.



Copper. Copper is required component of many redox enzymes, including cytochrome c oxidase. Copper is a critical functional component of a number of essential enzymes known as cuproenzymes. The copper-dependent enzyme, cytochrome c oxidase, plays a critical role in cellular energy production. By catalyzing the reduction of molecular oxygen (O2) to water (H2O), cytochrome c oxidase generates an electrical gradient used by the mitochondria to create the vital energy-storing molecule, ATP. Another cuproenzyme, lysyl oxidase, is required for the cross-linking of collagen and elastin, which are essential for the formation of strong and flexible connective tissue. A number of reactions essential to normal function of the brain and nervous system are catalyzed by cuproenzymes. Copper is also important in neurotransmitter synthesis. The enzyme Dopamine-b-monooxygenase catalyzes the conversion of dopamine to the neurotransmitter norepinephrine. Monoamine oxidase (MAO) plays a role in the metabolism of the neurotransmitters norepinephrine, epinephrine, and dopamine. MAO also functions in the degradation of the neurotransmitter serotonin, which is the basis for the use of MAO inhibitors as antidepressants. Copper is also vital for the formation and maintenance of myelin sheath; made of phospholipids whose synthesis depends on cytochrome c oxidase activity. Copper-dependent transcription factors also regulate transcription of specific genes. Genes regulated by copper-dependent transcription factors include genes for copper/zinc superoxide dismutase (Cu/Zn SOD), catalase (another antioxidant enzyme), and proteins related to the cellular storage of copper.



Fluorine. Fluorine deficiency is a medical condition in which a human, or other organism lacks the necessary compounds containing fluorine (or fluoride) to keep bones and teeth healthy. Fluorine is required for tooth enamel, which contains fluoroapatite. The extent to which the condition truly exists, and its relationship to fluoride poisoning has given rise to some controversy, expecially since excessive levels can be toxic to the body.



Iodine. Iodine is an essential constituent of hormones produced by the thyroid gland required for the biosynthesis of thyroxin. In the fetus, iodine is necessary for the development of the nervous system. Iodine is required in larger quantities than the other trace minerals in this list and is sometimes classified with the bulk minerals.



Iron. Iron has the longest and best described history among all the micronutrients. It is a key element in the metabolism of almost all living organisms. In humans, iron is an essential component of hundreds of proteins and enzymes, most notably hemoglobin. Ribonucleotide reductase is an iron-dependent enzyme that is required for DNA synthesis. Thus, iron is required for a number of vital functions, including growth, reproduction, healing, and immune function. Anemia, caused by iron deficiency, is characterized by low haemoglobin and is the most widely recognized symptom of iron deficiency, but it also causes other serious problems such as impaired learning ability in children, increased susceptibility to infection and reduced work capacity. Women of childbearing age are especially prone to iron deficiency and suffer from tragic consequences such as premature childbirth, babies with low birth weight and even greater risk of death



Manganese. Manganese plays an important role in a number of physiologic processes as a constituent of some enzymes and an activator of other enzymes. Manganese is required for the processing of oxygen (Manganese superoxide dismutase (MnSOD) is the principal antioxidant enzyme in the mitochondria). A number of manganese-activated enzymes play important roles in the metabolism of carbohydrates, amino acids, and cholesterol). For instance, pyruvate carboxylase, a manganese-containing enzyme, and phosphoenolpyruvate carboxykinase (PEPCK), a manganese-activated enzyme, are critical in gluconeogenesis— the production of glucose from non-carbohydrate precursors. Arginase, another manganese-containing enzyme, is required by the liver for the urea cycle, a process that detoxifies ammonia generated during amino acid metabolism. Manganese is the preferred cofactor of enzymes called glycosyltransferases; these enzymes are required for the synthesis of proteoglycans that are needed for the formation of healthy cartilage and bone. Manganese is also required for the activation of prolidase, an enzyme that functions to provide the amino acid, proline, for collagen formation in human skin cells and may also play an important role in wound healing.



Molybdenum. Molybdenum is an essential trace element for virtually all life forms. It functions as a cofactor for a number of enzymes that catalyze important chemical transformations. Molybdenum is known to function as a cofactor for three enzymes: Sulfite oxidase, Xanthine oxidase and Aldehyde oxidase. Sulfite oxidase catalyzes the transformation of sulfite to sulfate, a reaction that is necessary for the metabolism of sulfur-containing amino acids (methionine and cysteine). Xanthine oxidase catalyzes the breakdown of nucleotides (precursors to DNA and RNA) to form uric acid, which contributes to the plasma antioxidant capacity of the blood. Aldehyde oxidase and xanthine oxidase catalyze hydroxylation reactions that involve a number of different molecules with similar chemical structures. Xanthine oxidase and aldehyde oxidase also play a role in the metabolism of drugs and toxins. Of these three enzymes, sulfite oxidase is known to be crucial for human health.



Nickel. Nickel can activate or inhibit a number of enzymes. It is also known that the production or action of specific hormones (such as adrenaline, aldosterone, noradrenaline, and prolactin) responds to changes in nickel concentration within the body. Studies have shown that also nickel alters cell membrane properties and influences oxidation/reduction systems. Although it is difficult to induce a deficiency because the requirement is low and nickel comes from a variety of sources nickel deficiency has been linked to low blood glucose levels, abnormal bone growth, poor absorption of ferric iron, and altered metabolism of calcium, vitamin B-12 and energy nutrients.



Selenium. Humans and animals require selenium for the function of a number of selenium-dependent enzymes, also known as selenoproteins. Selenium is also required for peroxidase (antioxidant proteins) among a variety of other important bodily functions. These antioxidant enzymes reduce potentially damaging reactive oxygen species (ROS), such as hydrogen peroxide and lipid hydroperoxides, to harmless products like water and alcohols by coupling their reduction with the oxidation of glutathione (diagram). Recent studies show clear evidence that selenium can prevent certain cancers and stimulate immune function, but the quantity of selenium required to exert these protective effects is currently not known.



Zinc. Zinc is an essential trace element for all forms of life. The significance of zinc in human nutrition and public health was recognized relatively recently. Zinc plays a critical role in the body. Zinc deficiency is also widespread in many countries throughout the world, and has been found to be the most widespread micronutrient deficiency. Numerous aspects of cellular metabolism are zinc-dependent. Zinc also plays important roles in growth and development, the immune response, neurological function, and reproduction. Zinc is required for several enzymes such as carboxypeptidase, liver alcohol dehydrogenase, carbonic anhydrase.


What can be done individually about micronutrient deficiencies?

What can be done about the above listed deficiencies? There are several things. (1) try to eat organically and improve your diet, and your cooking methods. Another common and effective way is dietary supplementation. Micronutrient supplement can be purchased individually, or they can be purchased in various combinations. Today there are many good micronutrient supplements being sold today that include essential vitamins and minerals, a broad spectrum of potent antioxidants, an array of important amino acids, bioflavanoids, herbal extracts and enzymes that are often deficient in many people's diets today. Starting out with a good broad based combination supplement is often a good place to start since it is often very difficult for the average person to determine which individual supplement compound they may need, as well as how to determine what dosage levels to take and whether there will be any interaction among the compound taken