Question

This week we learned about nutrition and read about Carbohydrates, Proteins, Fats, Vitamins, Folic Acid, Antioxidants and Phytochemicals, Minerals, Calcium, Iron, Sodium, and Water. Focus on one of these and discuss them in detail. What is this dietary element role in the body? How much is recommended? What are some of the most nutrient rich foods that contain your selected element? Do you believe that you get enough, too little, or too much in your daily diet? What are the consequences of too much?

Answer 1

Nutrition is the study of how food and drink affects our bodies with a special regard to the essential nutrients necessary to support human health. Poor nutrition can lead to a lack of energy, digestive problems, food allergies, weight gain, depression and anxiety as well as many of today’s most prevalent chronic diseases like coronary heart disease, cancer etc.

Essential nutrients are compounds that the body can’t make or can’t make in sufficient quantity. According to the World Health Organization and these nutrients must come from food, and they’re vital for disease prevention, growth, and good health. So the essential nutrients are

• Proteins
• Carbohydrates
• Fats
• Vitamins
• Minerals
• Water

Minerals are essential for many body functions, including building strong bones and teeth, regulating your metabolism, and staying properly hydrated. Some of the most common minerals are calcium, iron, and zinc.

Iron

Iron is vital for all living organisms because it is essential for multiple metabolic processes, including oxygen transport, DNA synthesis, and electron transport etc. Iron equilibrium in the body is regulated carefully to ensure that sufficient iron is absorbed in order to compensate for body losses of iron. It is associated with proteins either through ligand binding or by being incorporated into a porphyrin group - a ring-shaped molecule. A complex of the ferrous form of iron and protoporphyrin IX is known as heme. Heme iron is found in proteins connected with oxygen transport, including haemoglobin and myoglobin. Non-heme iron can be found in proteins connected with oxidative phosphorylation and in iron storage proteins like transferrin and ferritin.

About 70 percent of iron in the body is found in haemoglobin and myoglobin. Hemoglobin is the protein in red blood cells responsible for carrying oxygen to the tissues from the lungs. Myoglobin is a protein found in muscles that is used for storage of oxygen.    

Iron requirements

During early infancy, iron requirements are met by the little iron contained in the human milk. The need for iron rises markedly 4-6 months after birth and amounts to about 0.7-0.9 mg/day during the remaining part of the first year. Between 1 and 6 years of age, the body iron content is again doubled. Iron requirements are also very high in adolescents, particularly during the period of growth spurt. The daily or recommendations or requirement of iron is different in humans according to age and sex. The following tables illustrate the daily recommended amount of iron as per the WHO guidelines,

Age	Male	Female	Pregnancy	Lactation
Birth to 6 months	0.27 mg*	0.27 mg*
7–12 months	11 mg	11 mg
1–3 years	7 mg	7 mg
4–8 years	10 mg	10 mg
9–13 years	8 mg	8 mg
14–18 years	11 mg	15 mg	27 mg	10 mg
19–50 years	8 mg	18 mg	27 mg	9 mg
51+ years	8 mg	8 mg

Sources of Iron

The richest sources of heme iron in the diet include lean meat and seafood. Dietary sources of nonheme iron include nuts, beans, vegetables, and fortified grain products. In the United States, about half of dietary iron comes from bread, cereal, and other grain products. Breast milk contains highly bio-available iron but in amounts that are not sufficient to meet the needs of infants older than 4 to 6 months.

Food	Mg per Serving	Daily Value
Breakfast cereals, fortified with 100% of the DV for iron, 1 serving	18	100
Oysters, eastern, cooked with moist heat, 3 ounces	8	44
White beans, canned, 1 cup	8	44
Chocolate, dark, 45%–69% cacao solids, 3 ounces	7	39
Beef liver, pan fried, 3 ounces	5	28
Lentils, boiled and drained, ½ cup	3	17
Spinach, boiled and drained, ½ cup	3	17
Tofu, firm, ½ cup	3	17
Kidney beans, canned, ½ cup	2	11
Sardines, Atlantic, canned in oil, drained solids with bone, 3 ounces	2	11
Chickpeas, boiled and drained, ½ cup	2	11
Tomatoes, canned, stewed, ½ cup	2	11
Beef, braised bottom round, trimmed to 1/8” fat, 3 ounces	2	11
Potato, baked, flesh and skin, 1 medium potato	2	11
Cashew nuts, oil roasted, 1 ounce (18 nuts)	2	11
Green peas, boiled, ½ cup	1	6
Chicken, roasted, meat and skin, 3 ounces	1	6

Deficiency and Overdose

Iron deficiency is defined as a condition in which there are no mobilizable iron stores and in which signs of a compromised supply of iron to tissues. Iron deficiency results from depletion of iron stores and occurs when iron absorption cannot keep pace over an extended period with the metabolic demands for iron to sustain growth and to replenish iron loss, which is primarily related to blood loss. The World Health Organization (WHO) estimates that approximately half of the 1.62 billion cases of anaemia worldwide are due to iron deficiency. In developing countries, iron deficiency often results from enteropathies and blood loss associated with gastrointestinal parasites. Pregnant women, infants and young children, women with heavy menstrual bleeding, cancer patients are vulnerable groups if not taken care properly. Best way to manage the iron deficient is balanced diet and iron supplements. For oral iron supplementation, ferrous iron salts (ferrous sulphate and ferrous gluconate) are preferred because of their low cost and high bioavailability.

Iron overdose or high intake is very harmful and lead to many complications to the human body. Several conditions may cause this to happen. These include: Iron poisoning: Poisoning can occur when people, usually children, overdose on iron supplements. Hereditary hemochromatosis: A genetic disorder characterized by excessive absorption of iron from food. African iron overload: A type of dietary iron overload caused by high levels of iron in food or drinks. It was first observed in Africa, where homemade beer was brewed in iron pots.