Min trace elements

Minerals and trace
elements
Dr K N Prasad MD., DNB.
Community Medicine


Seven Food Substances
Dietary Fibre

Water

Minerals

Food Substances

Proteins

Vitamins

Fats
Carbohydrates


Minerals
 50 chemical elements are identified
 Important 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


Iron
 Adult human body contains 3-4 Gm
 60-70% is present in Blood and rest in storage form.
 Each Gm of Hb contains 3.34mg of Iron.

Requirement :
 1 mg per day for Male
 2.5 mg for Females
 3.5 mg for Females in Physiological stress
conditions


Functions of iron
 Iron is a part of all cells and has many different
functions
 Hb Carries of oxygen to the tissues
 Brain development along with Folic acid

 Myoglobin Facilitates oxygen use and storage in
muscles
 An integral part of enzyme reactions in various tissues
( Cyotchromes, Catalases, etc)
 Regulation of Body temperature
 Catecholamine metabolism
 Susceptibility 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 problem
 Categorized 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 anemic
 Iron deficiency in young children is the rule rather

than the exception (from 45 to 70 percent prevalence
 Anemia 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 causes
IUCD may loss result in blood loss

Storage
Stored in Liver, Spleen, Bone marrow,
Kidneys


Iron Deficiency
 Occurs in 3 stages:
 First Stage: Decreased storage without any other
detectable abnormalities
 Second 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:
Fatigue
Headache
Exertional dyspnoea
Cardiovascular stress
Poor 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)


Correction of Iron Deficiency
Oral iron supplements
100 200 mg elemental iron daily
Higher doses are of no benefit
Ferrous sulphate 65mg/tab
Pregnant women- 100mg/tablet (+ folic

acid)



Iodine
 Essential Micronutrient
 Body 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 & Variable
 Small 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 iodide
 occurs both as free and protein-bound iodine in
circulation
 iodine is stored in the thyroid where it is used for
the synthesis of T3 and T4
 hormone is degraded in target cells and in the
liver and the iodine is conserved if needed
 excretion is primarily via urine
 small 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 assessment
 Prevalence of Goitre
 Prevalence of Cretinism
 Urinary iodine excretion
 Prevalence of Neurological hypothyroidism
 Thyroid 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 forms

 96% 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