Nutrition being a very broad and expansive topic in itself, the ppt aimed at summing it up, giving a few basic concepts to MBBS students in a very short span, and make them capable of carrying out a brief nutritional assessment of their patients in future and provide them with some meaningful counseling and advice.

1. Common Sources of Various
Nutrients & Special
Nutritional Requirements
According to Age, Sex,
Activity & Physiological
Conditions
Dr. Smriti Verma (JR-III)
Dept. Of Community Medicine
& Public Health
KGMU, UP, Lucknow

2. Introduction
• The term "nutrition" is derived from the Latin word nutritic, meaning
nourishment.
• Good nutrition forms the basis of good health and protection from
diseases.
• In simple terms, nutrition refers to the process of intake, digestion,
and assimilation of nutrients and the application of this
knowledge to maintenance of health and prevention of disease.
• A well-nourished community is a basic pre-requisite for successful
economic and social development of a country and thus, nutritional
status has been internationally recognized as an indicator of
adequate national development.

3. Proximate
principles and
Energy
• Proximate principles in nutrition are the
immediate constituents of food that provide the
body with energy, growth, and maintenance.
• These proximate principles include proteins, fats,
and carbohydrates.
• Each of these proximate principles plays a
specific role in maintaining optimal nutrition and
overall health.
• Understanding the proximate principles in
nutrition is essential for maintaining a balanced
and healthy diet.

4. Slide 4: Proteins
Proteins are macromolecules
consisting of amino acid chains linked
together by peptide linkages.
In an average adult, approximately 16%
of the body weight is attributable
to proteins.
Next to only water, proteins constitute
the most major component of living
tissues.
They are indispensable constituents of
living protoplasm as they participate
in all vital processes.
22 amino acids are now known to
be physiologically important for the
human body.

5. Proteins
Under normal, healthy conditions the body is capable of synthesizing some of these amino
acids known as non-essential amino acids.
Others cannot be synthesized by our body and therefore, must be supplied through diet.
These are the 8 "essential amino acids" namely,
leucine, isoleucine, lysine, valine, methionine, threonine, tryptophan, and phenylalanine.
Another amino acid that can be added to this list is histidine, which is deemed essential for
infant growth.

6. Sources
RDA for Proteins:
Generally accepted value is 1g/kg body wt./day assuming an NPU of 65 for
most Indian foods.
Thus, the RDA for a reference adult male works out to approximately
60g/day and that for a female comes out to be 55g/day.
Children have a higher RDA due to additional requirements of growth and
development.
Major Sources of Proteins and their Protein Content
(g/100g)
Animal Sources Protein Content (g) Vegetable
Sources
Protein Content (g)
Eggs 13.3 Soya bean 43.2
Milk (cow) 3.2 Groundnut 25.3
Meat (goat, lean) 21.4 Wheat flour 12.1
Fish (Hilsa) 21.8 Rice (raw, milled) 6.8
Pulses (red gram) 22.3
Almonds 21

7. • Fats are organic compounds, insoluble in polar
solvents (water) but soluble in organic solvents such
as ether, chloroform, and benzene.
• Chemically, they are actual or potential esters of fatty
acids.
• They perform many essential functions in the human
body, including forming a protective layer for all
living tissues and vital organs, such as the heart,
kidneys, lungs and liver.
• They are a much concentrated source of
energy, providing more than twice the amount of
calories per gram as compared to carbohydrates and
proteins.
This Photo by Unknown author is licensed under CC BY-NC-ND.
Fats

8. Fats
• The same makes them an excellent, long-term, sustained source of energy. However, it is
crucial to consume them in moderation as an excess could easily prove to be hazardous by
contributing to rapid weight gain and increasing the risk of chronic ailments like heart disease,
diabetes and certain types of cancer.
RDA for fats
• Fats such as cooking oil, ghee, and vanaspati are called visible fats; sedentary adult
female requires 20g and male requires 25g of visible fats per day.
• However, diets of growing children need to be relatively richer in order to provide them with
requisite number of calories as large quantities of diets rich in cereals cannot be consumed by
them. Therefore, young children require 30-50g of visible fats per day.

9. Composition of fats
• Fats are made up of fatty acids, which may be saturated, mono or poly unsaturated fatty acids.
• Animal foods are the predominant sources of saturated fatty acids.
• Fats obtained from plant sources are usually unsaturated. An exception is coconut oil which
contains as much as 92% saturated fatty acids.
• The human body is also capable of synthesizing saturated fatty acids during catabolism of
carbohydrates and proteins.
• Lauric acid, palmitic acid and stearic acid are examples of saturated fatty acids (SFA).
• The number of chains of carbon atoms in most SFAs is even, ranging from 4 to 24. Those with less
than 10 are classified as small, 12-14 as medium, and 16-24 as long chain fatty acids.
• Out of these, short and medium chain fatty acids are good for infants and young children as they are
readily digestible. However, they are not good for adults since they are also highly atherogenic.
• SFAs should not constitute more than 10% of the energy intake.
This Photo by Unknown author is licensed under CC BY-SA.

10. Composition of fats
• Unsaturated fatty acids are primarily derived from vegetable sources.
• The body can synthesize monounsaturated fatty acids but it cannot
synthesize polyunsaturated fatty acids.
• Oleic acid is an example of monounsaturated fatty acid.
• Linoleic, arachidonic, eicosapentaenoic acid, and docosahexaenoic acid
are polyunsaturated fatty acids. These have to be obtained from diet and
are thus, called essential fatty acids.
• Unsaturated fatty acids have double bonds which can either be cis or
trans, based on the location in relation to the acyl chain.
• When the double bond is in the trans configuration, the fatty acids are
called trans fatty acids(TFA).
• The World Health Organization (WHO) recommends that less than 1% of
total energy intake should come from trans fat, which is less than 2.2
grams per day for a 2,000-calorie diet

11. Sources
Types of fatty acids from different sources
Saturated Monounsaturated Polyunsaturated
• Coconut
• Palm kernel
• Ghee/butter
• Vanaspati
• Red palm oil
• Palmolein
• Groundnut
• Rice bran
• Sesame
Linoleic (n-6) Linolenic (n-3)
Low Red palm oil,
palmolein
Rapeseed,
Mustard,
Soya bean
Moderate Groundnut,
rice bran,
sesame
High Safflower,
sunflower,
cottonseed,
corn, soya
bean

12. Slide 3:
Carbohydrates
• Carbohydrates constitute the largest energy yielding
chunk especially in Indian diets.
• About 80% of the calories for Indians come from the
carbohydrates in cereals, pulses, and millets.
• The presence of fiber makes complex carbohydrate
consumption a healthier practice than consumption of
refined carbohydrates.
Glycemic Index: The glycemic index is a value assigned to
foods based on how slowly or quickly they bring about a
rise in blood glucose levels.
Foods low on GI tend to release glucose slowly, e.g., green
vegetables, most fruits, lentils.
Foods high on GI tend to release glucose rapidly, e.g.,
white rice, bread and potatoes.
The GI is a potential and quick tool to assess the effects of
particular foods on the post prandial blood glucose levels
and thus can be readily used to make a judgement about
what foods to consume in what quantity.

13. Sources
Types of Carbohydrates
Category Type of carbohydrate Source
Simple Glucose & fructose Fruits, vegetables, and honey
Sucrose Sugar
Lactose Milk
Complex Starch Cereals, millets, pulses, and root
vegetables
Glycogen Animal foods
Cellulose (dietary fiber) Vegetables and whole grains
Gums and pectins (dietary
fiber)
Vegetables, fruits, and cereals

14. • Vitamins are essential organic compounds that are vital for
the maintenance of our overall health and well-being.
• They play a crucial role in various bodily functions and are
required in small quantities to support proper growth,
development, and functioning of our bodies.
• They are essential micronutrients as they cannot be
synthesized in the human body.
• Fat soluble vitamins are A, D, E, and K. They can be stored
in the body.
• However, water soluble vitamins namely B and C being water
soluble are excreted out daily and hence need to be
supplemented daily.
• They are also easily destroyed by cooking, heating, and
processing.
Vitamins

15. Sources
Vitamin type Major sources
Vitamin A Carrots, sweet potatoes, spinach, kale, apricots, liver, eggs, milk,
cheese
Vitamin B1 Whole grains, meat, fish, legumes, nuts, seeds
Vitamin B2 Dairy products, lean meats, green leafy vegetables, eggs, mushrooms
Vitamin B3 Meat, poultry, fish, whole grains, legumes, nuts, seeds
Vitamin B5 Meat, poultry, fish, eggs, whole grains, legumes, avocados,
mushrooms
Vitamin B6
Vitamin B7 Eggs, organ meats, nuts, seeds, sweet potatoes

16. Sources
Vitamin type Major sources
Vitamin B9 Leafy green vegetables, legumes, liver, orange juice, fortified grains
Vitamin B12 Shellfish, fish, meat, poultry, eggs, dairy products, fortified foods
Vitamin C Citrus fruits, berries, kiwi, tomatoes, peppers, broccoli, spinach
Vitamin D Fatty fish, fortified dairy products and plant-based milks, sunlight
exposure
Vitamin E Nuts, seeds, vegetable oils, fortified cereals, spinach, broccoli
Vitamin K Leafy green vegetables, broccoli, Brussels sprouts, peas, beans

17. Slide 7: Minerals
• Minerals are essential nutrients that are critical in
small amounts for proper functioning of the
body.
• They are involved in various physiological
processes, including bone development, nerve
function, and energy production.
• Calcium, magnesium, phosphorus,
potassium, sodium, and sulfur are required in
relatively larger amounts and are called macro-
minerals.
• While copper, cobalt, chromium, fluorine, iron,
iodine, molybdenum, selenium, and zinc are the
important micro-minerals.

18. Important Minerals
Calcium
• Calcium is mainly found in the bones. It is a major mineral and it is estimated that an adult
man weighing 65 kg would have around 1kg of this element in his body.
• It is required in the body for bone formation, neuromuscular excitation, blood coagulation, and
membrane permeability.
• When the intake of this mineral through diet is insufficient, the calcium in the bones helps to
maintain the blood levels. This bone turnover and calcium absorption and excretion are
regulated by hormones like Vitamin D, parathormone (PTH), thyrocalcitonin, and other steroids
in the body.
• Requirements: Intake of calcium is recommended at 1000mg/day for adults, 1000mg/day for
pregnant females and an additional 200mg/day for lactating mothers. Adolescents require
around 850mg of the mineral per day.
• Its important sources include, milk, cereals like ragi, and leafy vegetables like spinach and
kale.
This Photo by Unknown author is licensed under CC BY-SA-NC.

19. Important Minerals
Iron
• According to the National Nutrition Monitoring Bureau (NNMB) in most states in India,
the iron intake is less than 50% of the actual RDA.
• Iron is an extremely essential mineral that is required for the vital function of
hemoglobin synthesis in the human body.
• Its deficiency can lead to a variety of conditions ranging from, anemia, improper mental
functioning and susceptibility to infections to poor learning in children.
• Children and women of the reproductive age group are known to be more vulnerable to
its deficiency.
• Iron absorption is only 5% in India except in adult women in whom it can be upto 10%.
This Photo by Unknown author is licensed under CC BY-NC-ND.

20. Important
Minerals
Iron
• Requirements: In adult males, the daily iron is required to
replenish the basal iron lost through desquamated GI
cells, bile, urine and sweat.
• Additionally, in females, iron is lost through menstruation.
• Therefore, and average adult male requires about 19mg of
iron/day. Whereas, an average adult female requires 29mg
of iron/day. A pregnant female requires around 40mg
iron/day and a lactating female requires 23mg iron/day.
• Important sources of iron include, animal foods like fish,
meat, poultry. Plant sources include dried foods like dates,
jaggery and legumes.

21. Important Minerals
Magnesium
• A normal, healthy adult holds around 20-25g of magnesium in his body.
• It is found in muscles, soft tissue and extracellular fluid apart from bones.
• It maintains the electrical potential in membranes and nerves.
• Since magnesium is widely distributed in foods, its deficiency is unlikely
to occur unless an individual suffers from some malabsorption
syndrome.
Requirements: 325 mg/day for adult female and 385mg/day for adult male.
• Foods rich in magnesium include nuts (almonds, cashews), seeds
(pumpkin, sunflower), legumes, whole grains, and dark chocolate.
This Photo by Unknown author is licensed under CC BY-SA.

22. Important Minerals
Zinc
• Zinc is important for immune function, wound healing, and DNA synthesis.
• It is known to reduce the incidence and severity of childhood illnesses like pneumonia and
diarrheal diseases.
• During diarrheal episodes, zinc supplementation is recommended.
• Zinc is also known to have a role in reducing the morbidity and mortality of children. In
undernourished children, zinc promotes weight gain.
Requirements: The RDA for zinc for adult male and female is set at 17 and 13 mg/day respectively.
• Its important sources include eggs, liver, fish and milk. Among plant foods, grains, pulses,
legumes, and nuts provide zinc.
• Milling and other processing methods reduce the zinc content in plant foods.
This Photo by Unknown author is licensed under CC BY-SA-NC.

23. Important
Minerals
Sodium
• Sodium is responsible for maintaining the water balance in the body and
blood pressure.
• The requirement of this element depends on the loss. But even with a loss
of up to 3 litres of sweat in 6 hours, the sodium requirement does not
go beyond 8g/day.
• Common salt is the most important source of this element but
its overuse especially in the Indian setting over the years has led to an
epidemic of hypertension and metabolic disorder in the country.
• Indians consume 5-30g of salt/day.
• It is imperative to note that40% of Indian families consume more than 10g of
salt/person/day.
• However, it is imperative to note that the taste of salt is an acquired habit.
Hence, if restricted from a young age, its consumption can be effectively
reduced.

24. Recommended Dietary Allowances (RDA) for energy, protein, fat and minerals for Indians

25. Balanced diet plan for Indians (quantities in grams)

26. Balanced diet plan for Indians (quantities in grams)

27. Recommended Dietary Intake (RDI) per Consumption Unit (CU)

28. Special
Nutritional
Requirements
• While basic nutritional principles apply
universally, it's essential to recognize the
individualized nutritional needs that can
vary significantly based on several
factors.
• These factors include, age, sex, level of
physical activity and other physiological
or pathological conditions.
• As variable as the needs and
preferences of every individual could be,
getting a general idea of the
requirements in due consideration with
common factors of concern could go a
long way in planning and evolving
healthy eating patterns in the long run.

29. Special Nutritional Requirements
Age-related Nutritional Requirements
Infants:
• All the essential nutrients required by the baby during the first 6
months of life can be obtained through breast milk.
• The nutrients in breast milk are easily digestible and readily
absorbable for the baby. Apart, from all the requisite nutrients,
breast milk also has an abundance of immunoglobulins (IgA),
lactoferrin, lactoperoxidase and complements which protect the
infant from several infections.
This Photo by Unknown Author is licensed under CC BY-SA-NC

30. Special Nutritional Requirements
Complementary or Supplementary Feeding after 6 months:
• After 6 months, mothers' milk proves inadequate to meet all the
nutritional requirements of the baby, therefore, other feeds
namely, complementary or supplementary feeds are added to it.
• Cereal-pulse-nut combination with added sugar/ jaggery forms
one of the most commonly used and adequate complementary
foods.
• Later on, cooked and mashed semi-solid vegetables and fruits
or fruit juices can be added.
• Only one new food should ideally be introduced in a day.
• Amylase rich foods (ARF) like germinated and powdered cereal
flour are a preferred addition to the complementary feeds to
reduce bulk and make them energy dense.
This Photo by Unknown author is licensed under CC BY-NC.

31. Special Nutritional Requirements
Childhood & Adolescent Nutrition
• These are stages of rapid growth and development.
• Taking adequate calcium in the form of milk or other calcium rich foods
to get at least 600-800 mg/day is important.
• Oil intake of 25-50g according to the age group is recommended.
• Care should be taken to avoid excessive consumption of salt especially
if there is a family history of CHD.
• This period should also be given importance as the phase where
most healthy eating patterns and habits can be effectively developed
and erroneous ones challenged and modified.
This Photo by Unknown author is licensed under CC BY-NC-ND.

32. Special Nutritional Requirements
Nutrition for Elderly
• Due to changes in elderly like the reduction of lean body mass, basal metabolic rate, and physical
activity, the amount of energy/calories required decreases dramatically.
• After 40 years, the energy needs decrease by 5% for every decade of life till age 60. Thereafter, the
requirements decrease by 10% every decade.
• High protein diets and the use of commercially available high protein supplements is not
recommended although due to reduction in overall quantity of food consumed, a deficiency of proteins
is likely to occur. The same can be dealt with by improving upon the quality of proteins consumed.
• High fat diets should be kept at bay in view of increased prevalence of most chronic diseases in the
elderly.
• Cardiovascular risk can be reduced by upto 30%, , if the vegetable and fruit intake is increased by two
portions.

33. Special Nutritional Requirements
Physiological Conditions and Nutritional Requirements
Pregnancy and Lactation
• The additional requirement of calories is 350 kcal.
• Taking fiber rich foods is essential to curb constipation. (25g/1000 kcal)
• Consumption of 8-12 glasses of water is advisable and salt should be restricted to <5g/day.
• There is also an increased need for folic acid, iron, calcium, and protein to support fetal growth and
development.
• The dietary patterns may require drastic changes if not already balanced in the pre-pregnancy state.
• If the nutritional requirements are adequately met, a weight gain of 10-12kg is anticipated in a pregnant
female.

34. Special Nutritional Requirements
Gender-specific Nutritional Requirements
- Males: Typically have higher caloric needs due to higher
muscle mass. May require more protein to support muscle
growth. Iron needs are generally lower.
- Females: May require more iron to account for
menstruation. Calcium needs may be higher to support
bone health. Protein needs are generally similar to males.
This Photo by Unknown author is licensed under CC BY-SA-NC.

35. Special Nutritional Requirements
Activity-related Nutritional Requirements
- Active individuals: Need more calories to support
energy expenditure. Carbohydrates are important
for fueling physical activity. Protein is necessary for
muscle repair and growth.
- Sedentary individuals: Need fewer calories.
Emphasis should be on nutrient-dense foods to
meet nutritional needs without excess calorie
intake.
This Photo by Unknown author is licensed under CC BY-NC.

36. Thank you!