Minerals and trace Minerals and trace elementselements

Dr K N Prasad MD., DNB.

Community Medicine

Seven Food Substances

Food Substances

Carbohydrates

Proteins

Water

Dietary Fibre Minerals

Vitamins

Fats

Minerals

50 chemical elements are identifiedImportant for Growth, Development , regulation

of vital functions

Major : calcium, Phosphorous, Sodium, Potassium, Magnesium

Minor: Required less than a few milligram per day. Ex. Iron, Iodine, Fluorine, Zinc, Copper, Cobalt, Chromium, Manganese, Molybdenum, Selenium, Nickel, Tin, Silicon, Vanadium

Trace elements

A naturally occurring, homogeneous, inorganic substance required in humans in amounts less than 100 mg/day

Bioavailability of minerals are low in vegetarian diet.

Excess amounts are injurious to health

IronAdult human body contains 3-4 Gm60-70% is present in Blood and rest in storage form.Each Gm of Hb contains 3.34mg of Iron.

Requirement : 1 mg per day for Male2.5 mg for Females3.5 mg for Females in Physiological stress

conditions

Functions of ironIron is a part of all cells and has many different

functionsHb Carries of oxygen to the tissuesBrain development along with Folic acidMyoglobin Facilitates oxygen use and storage in

musclesAn integral part of enzyme reactions in various tissues

( Cyotchromes, Catalases, etc)Regulation of Body temperatureCatecholamine metabolismSusceptibility to infection

Sources of iron

Haem Iron: Liver, meat, poultry, Fish

Non Haem Iron: Cereals, GLV, Legumes,, Nuts, Oil seeds, Dried

Fruits, Jaggery

Factors interfere in absorption are enzymes in the food – Phytates, Oxalates, Phosphates, Dietary fibres

Ascorbic acid is the most potent enhancer iron

Public Health problemCategorized as one of the top ten most serious health

problems in the modern world (WHO) As many as 4-5 billion people (66-80% of

population) may be iron deficient 2 billion people (>30% of population) are anemicIron deficiency in young children is the rule rather

than the exception (from 45 to 70 percent prevalenceAnemia is a fact of life for almost 500 million of

women of childbearing age(~40% of 15 to 40 y old females in developing world)

More than 1,000 severely anemic young women die every week in the perinatal period because of inadequate iron status

Iron loss

In adults – 1 mg per day Menstruating women – 2 mg per day

Hemorrhages are common causesIUCD may loss result in blood loss

StorageStorageStored in Liver, Spleen, Bone marrow, Stored in Liver, Spleen, Bone marrow,

KidneysKidneys

Iron DeficiencyOccurs in 3 stages:First Stage: Decreased storage without any other

detectable abnormalitiesSecond Stage: stores are exhausted, serum

Ferritin level decreases.Third Stage: Decrease in Hemoglobin percentage

Functional disturbances: decrease in resistance to infection, increase morbidity & mortality, decreased work performances, impaired cell mediated immunity

Iron

Signs of iron deficiency anemia include:FatigueHeadacheExertional dyspnoeaCardiovascular stressPoor tolerance to heavy blood loss

Evaluation of iron status

1. Hemoglobin Concentration: relative index of iron deficiency. ( early Anemia if Hb is 10-11g% & marked anemia Hb is < 10g%).

2. Serum Iron concentration: useful index ( Normal 0.8 to 1.8mg /L)

3. Serum Ferritin level: Gold standard & sensitive tool for evaluation and reflects the size of the iron status ( < 10Micrgms/L)

4. Serum Transferrin Saturation: 16% - 30%

Correction of Iron Deficiency

Oral iron supplements100 200 mg elemental iron dailyHigher doses are of no benefitFerrous sulphate 65mg/tabPregnant women- 100mg/tablet (+ folic

acid)

IodineEssential MicronutrientBody normally has 20-30 mg of iodine and more than

75% is in the thyroid gland, rest is in the mammary gland, gastric mucosa, and blood it’s only function is related to thyroid Hormone

Required for synthesis of thyroid hormone Thyroxin (T4) – 4 atoms of iodine per molecule Triiodothyronine (T3) – 3 atoms of iodine per molecule

Requirement per day is 150 micrograms

Iodine Food Sources – 90% intake Foods of marine origin (seaweed), processed foods,

iodized salt Fresh Water – small & VariableSmall amounts in Milk, meat, Vegetables, Cereals

etc.

Goitrogens occurring naturally in foods can cause goiter by blocking absorption or utilization of iodine (cabbage, turnips, peanuts, soybeans)

Iodine - Absorption and Excretion

Iodine is absorbed in the form of iodideoccurs both as free and protein-bound iodine in

circulationiodine is stored in the thyroid where it is used for

the synthesis of T3 and T4hormone is degraded in target cells and in the

liver and the iodine is conserved if neededexcretion is primarily via urinesmall amounts from bile are excreted in the feces

Iodine - deficiency Goitre—enlargement of the thyroid gland deficiency may be absolute—in areas of deficiency, or relative—adolescence, pregnancy, lactation goiters are more prevalent in women and with increased age Iodine deficiency is the world’s most prevalent cause of brain

damage Serious iodine deficiency during pregnancy may result in

stillbirths, abortions and cretinism the less visible, more pervasive form of iron & iodine

deficiency that lowers intellectual performance at home and school may have far greater global and economic impact

Public Health problem of Iodine By the year 2000, Global prevalence of iodine deficiency from 30% to <15% Adding iodine to 2/3 of the world’s household salt 70 million newborns protected in some Degree Every year, 50 million children are born without the

protection that iodine offers to the growing brain and body About 18 million of those will suffer some significant

degree of mental impairment Iodine deficiency remains the single greatest cause of

mental retardation

The one third of the world’s people without protection by iodized salt are the most marginalized populations –economically, culturally and geographically

Sustainability is another battle: salt iodization is slipping back in several countries

Epidemiological assessmentPrevalence of GoitrePrevalence of CretinismUrinary iodine excretionPrevalence of Neurological hypothyroidismThyroid Function tests

Neonatal Hypothyroidism is a sensitive indicator of environmental iodine deficiency

Serum T4 is more sensitive indicator among adults

Fluorine It is found in combined forms96% of fluorides in the body found in bone and teeth.An essential for normal mineralisation of bones and

formation of dental enamel

Source: Drinking water : Fluorine in the drinking water is

0.5 mg per ltr. Excess of fl > 3mg causes flourosis.Foods: Sea fish, cheese, Tea

It is a two edged sword ( deficiency or excess)

Zinc Adult body contains 1.4 to 2.3 gms of Zinc Plasma level- 96Microgm per 100 ml ( adults), 89

Microgram per 100 ml (children)

Functions are Active role in metabolism of glucose and proteins Synthesis of insulin by pancreas Immunity functions

Food sources : meat, milk, fish Plant sources have low bioavailability

Zinc On of the ten biggest factors contributing to burden

of disease in developing countries Zinc interventions could reduce child deaths

globally by 63%

South East Asia and Sub-Saharan Africa highest risk of zinc deficiency:

Inadequate intake – 1/3 of the population Stunting – 40% of pre-school children Zinc used as a (part of) curative intervention for

severe malnutrition and diarrhoea

Zinc deficiency

1. Growth failure2. Sexual infantilism in adolescents, loss of taste,

delayed wound healing, decrease in immunosynthesis.

3. Spontaneous abortions, stillbirths, congenital malformations, anencephaly

4. LBW, Intra Uterine deaths, premature labour.

5. Requirement is 15mg for men

6. 12 mg for women, 10mg for children

Thought for the day

An advice is like snow,

the softer it falls,

the deeper it penetrates

and the longer it dwells.

Thank youThank you