Nutritional assessment is an extremely useful tool for
the application of nutritional therapy.
It includes both the screening and assessment of the
person’s nutritional status.
It is related to the individual’s
(1) food and nutrient intake (diet history),
(3) medication intake,
(4) social and medical history
(5) anthropometric, body composition and biochemical
• This dietary history should provide all the data needed
in order to evaluate the food and fluid intake.
Some of the most frequent and necessary information
• the usual dietary and meal plan, the number of
meals, the usual meal size and the common amount of
food, the usual location of eating,
• the consumption of ready-made meals, snacks and fast
• fluid intake, including the consumption of beverages
• possible food allergies, food preferences and the
frequency of consumption.
Body mass index BMI:
• BMI is the most recommended classification of body
weight and one of the simplest and most widely used
methods for the estimation of body fat.
BMI = Weight (kg) / Height (m2)
• BMI is an indicator of the stores of body fat, being
related to an increased danger of illness and mortality.
Classification of weight status by body mass index.
• Persons with a BMI <18.5 have an increased mortality
• BMI is not directly correlated with the accumulation
of body fat, and for this reason there are exceptions
(e.g. athletes, who have a very limited level of body fat
and cannot be classified as overweight or obese like
• The term ‘anthropometric’ refers to comparative
measurements of the body, which are used in
nutritional assessments in order to understand human
The anthropometric measurements which are used for
infants, children and adolescents usually include:
• Head circumference (length is used in infants and
toddlers, rather than height, because they are unable to
• The anthropometric measurements which are used for
adults usually include:
• Waist/hip ratio,
• Percentage of body fat.
• The waist/hip ratio (WHR) is the ratio of the
circumference of the waist to that of the hips and is
calculated by measuring the waist circumference, just
above the upper hip bone and dividing by the hip
circumference at its widest part.
• WHR of 0.9 for men and 0.7 for women has been
shown to correlate strongly with a general status of
• WHR over 1.0 for men and over 0.8 for women are
indicative of the presence of central obesity and
increased risk of related diseases (associated with
higher risk of diabetes and hypertension).
• WHR above 0.95 for men or 0.8 for women indicate a
heightened risk of heart attack.
Biochemical markers for nutritional evaluation:
• Serum albumin: The serum albumin level is an
indicative marker, for the nutritional evaluation of a
patient, although it has a relatively long half-life of 21
Patients with low serum albumin levels are in poor
nutritional condition and at high risk of death.
• Pre-albumin: Malnourished patients have significantly
lower levels of pre-albumin.
• Serum creatinine: it is used as a nutritional
marker, because of its relation to muscle mass.
Measuring serum creatinine is a simple test and it is
the most commonly used indicator of renal function.
• Serum transferrin: This is an iron-transport
protein, which serves as a sensitive marker of total
nutrition status and more specifically as a marker of
Dehydration is a fluid imbalance caused by inadequate
intake or excessive losses.
There are different biochemical markers that can
identify and reveal the presence of dehydration.
These markers are:
• Urea/creatinine ratio, which should be ≥0.15
• Elevated levels of plasma sodium
• Urine colour or specific urine gravity
• Serum osmolarity.
• It is recommended that the fluid intake should be at
least 500–750 ml greater than urinary losses, but it
should be even greater in cases of high temperatures or
the presence of burn or pyrexia or in the case of any
other reason of higher-than-normal losses.
• Dehydration is linked with constipation, medication
toxicity, renal failure, urinary tract infections, elevated
body temperature, dizziness and general weakness.
• Malnutrition: is a general term for a medical condition
caused by an improper or insufficient diet.
• The term usually refers to generally bad or faulty
nutrition and is most often related to undernutrition.
• Malnutrition is the ‘cellular imbalance between supply of
nutrients and energy and the body’s demand for them to
ensure growth, maintenance and specific functions’,
• it is the greatest risk factor for illness and death worldwide.
• It can be associated with both undernutrition and
Causes of malnutrition:
• The most common causes of malnutrition worldwide
are Anorexia, inadequate food intake or lack of food
supplies and loss of appetite.
• Anorexia can result from
pathophysiological, psychological and general social
• Different types of chronic and inflammatory diseases
can lead to reduced food intake and malnutrition.
• Also, nausea and vomiting and the use of certain drugs
or specific treatments (chemotherapy, radiotherapy)
may have a negative effect on appetite.
Protein and energy malnutrition:
The most common physical signs are:
• Weight loss and cachexia.
• Decreased subcutaneous tissue and reduction in
muscle and body tissue mass, which can be most often
observed in the legs, arms, buttocks and face.
• Neurological problems and abnormalities.
• Oral changes (red and usually swollen mouth, lips and
• Muscle cramp and pain.
• Skin changes (dry and
peeling, frail, swollen, pale, loss of elasticity and poor
• Hair changes (dry and discoloured).
• Cachexia is a wasting syndrome, regulated by
cytokines, and a condition of general ill
health, malnutrition, undesired weight loss and
• Cachexia is associated with various chronic and endstage diseases and medical conditions (e.g. metabolic
acidosis, infectious diseases, autoimmune disorders
and malignant conditions).
• Cachexia is characterized by changes in fat, protein
and carbohydrate metabolism such as increased
lipolysis, gluconeogenesis and protein turnover,
glucose intolerance and hyperinsulinaemia,
hyperlipidaemia, decreased plasma levels of branchedchain amino acids.
Kwashiorkor (from the West African word for
‘displaced child’) is a form of protein and energy
• The main cause of this form of malnutrition is
inadequate protein intake and the low concentration of
essential amino acids.
• Kwashiorkor is a severe form of undernutrition, which
develops in individuals on diets with a low
• The main symptoms of Kwashiorkor are oedema,
wasting, liver enlargement, hypoalbuminaemia,
steatosis and the possible depigmentation of skin and
• Marasmus (from the Greek word for ‘to waste away’)
is the other form of malnutrition, which is caused by
the inadequate intake of both protein and energy.
• It is a form of severe cachexia with weight loss as a
result of wasting in infancy and childhood.
• The main symptoms of marasmus are severe
wasting, with little or no oedema, minimal
subcutaneous fat, severe muscle wasting and non-
normal serum albumin levels.
• The main clinical signs of the most common
vitamin and mineral deficiencies:
• Food allergy refers to specific reactions that result
from an abnormal immunological response to a food
and which can be severe and life-threatening and
triggered by minute amounts of the allergen.
• Non-allergic food intolerance refers to reactions to
food that can result from a number of causes, none of
which is mediated by the immune system (e.g.
pharmacological effects, enzyme deficiencies, irritant
and toxic effects).
Types of food allergy:
• immunoglobulin E (IgE) mediated (early onset) and
non-IgE mediated (late onset, delayed).
• IgE mediated reactions generally present soon after
ingestion and thus easy to investigate and diagnose.
They can be more violent than non-IgE mediated
reactions and can even lead to death through
anaphylaxis in severe cases.
• Early-onset manifestations often include
wheezing, urticaria, angioedema, rashes, vomiting and
• whereas late-onset symptoms include
diarrhoea, abdominal pain, allergic rhinitis, atopic
eczema, food-sensitive enteropathy or food-sensitive
colitis, protein-losing enteropathy and constipation.
Food that cause allergy:
Common foods that can cause an allergic reactions:
• peanuts and tree nuts (e.g. hazelnut, Brazil
• milk (cow’s, goat’s, sheep’s),
• soya, fish, shellfish, eggs,
• seeds (especially sesame and caraway),
• fruits (especially
apples, peaches, plums, cherries, bananas, citrus
• and herbs and spices (especially mustard, paprika and
However, the most common allergies, according to the
frequency they occur, are:
• Children: cow’s milk, egg, soya, peanut, tree nuts, fish
• Adults: peanut, tree nuts, crustaceans, fish and egg.
The processing of food may also affect its allergenicity.
For example, the allergenicity of many fruits may be
greatly reduced by cooking, and that of eggs, milk and
some fish may be attenuated.
It is essential to ensure that:
• All potential sources of the allergen are avoided
• The effects of the exclusion diet on the intake of other
nutrients and overall dietary balance are minimised.