Dietary evaluation in the Dietary evaluation in the communitycommunityDr. Chamath FernandoDr. Chamath FernandoLecturerLecturerDepartment of Family MedicineDepartment of Family MedicineFaculty of Medical SciencesFaculty of Medical SciencesUniversity of Sri JayewardenepuraUniversity of Sri JayewardenepuraSri LankaSri Lanka

ObjectivesObjectives

To determine the populations who require To determine the populations who require nutritional evaluation and adjustmentnutritional evaluation and adjustment

To enumerate the tools for nutritional assessmentTo enumerate the tools for nutritional assessment

To identify the direct and indirect methods of To identify the direct and indirect methods of dietary evaluationdietary evaluation

Why assess diet?Why assess diet?

The purpose of nutritional assessment is to:The purpose of nutritional assessment is to:Identify individuals or population groups

at risk of becoming malnourished

Identify individuals or population groups

who are malnourished

To develop health care programs that meet the community needs which are defined by the assessment

To measure the effectiveness of the nutritional programs & interventions

Malnourished Malnourished

Under nourishedUnder nourished

Over nourished….

Malnourished

At community level…

Under nutrition in the global level

Therefore the dietary interventions implemented Therefore the dietary interventions implemented can be generalized to the population depending on can be generalized to the population depending on its overall need in the individual, family, its overall need in the individual, family, community and regional level.community and regional level.

Methods of Nutritional Methods of Nutritional AssessmentAssessment

Nutrition is assessed by methods

Direct methods - deals with the individual and measure objective criteria

Indirect methods - uses community health indices that reflects nutritional influences.

Direct methodsDirect methods

These are summarized as ABCDThese are summarized as ABCD

Anthropometry (e.g. height/length, weight, mid-arm circumference, triceps skinfold thickness, head circumference, waist-hip ratio) Use of growth monitoring charts…..

Biochemical parameters – (e.g. haemoglobin, albumin, measurement of individual nutrient in body fluids like serum retinol, serum iron, urinary iodine, vitamin D, urinary creatinine)

Clinical assessment – (e.g. general clinical examination, with special attention to organs like hair, angles of the mouth, gums, nails, skin, eyes, tongue, muscles, bones, & thyroid gland.)

Dietary evaluation

Indirect methodsIndirect methods

These include three categories:

Ecological variables including production of crops per annum.

Economic factors e.g. per capita income, population density & social habits

Vital health statistics particularly infant & under 5 mortality & fertility index

Dietary EvaluationDietary Evaluation

Five distinct methodsFive distinct methods11. . 24 hours dietary recall2. Food frequency questionnaire3. Dietary history since early life4. Food dairy technique5. Observed food consumption

1. 24-hour dietary recall1. 24-hour dietary recall

A trained interviewer asks the subject to recall all food & drinks taken in the previous 24 hours.

The exact food taken per each meal and snacks is documented along with the quantity consumed.

It is quick, easy, & depends on short-term memory

But may not be truly representative of the person’s usual intake

2. Food frequency 2. Food frequency questionnairequestionnaire

In this method the subject is given a list of around

100 food items to indicate his or her intake

(frequency & quantity) per day, per week & per

month.

inexpensive, more representative & easy to use.

Limitations:

long Questionnaire

Errors with estimating serving size.

Needs updating with new commercial food

products to keep pace with changing dietary

habits.

3. Dietary History3. Dietary History

It is an accepted method for assessing the nutritional status.

Collected by a trained interviewer.

Details about usual intake, types, amount, frequency & timing needs to be obtained in a chronological order.

Cross-checking to verify data is important.

4. Food diary4. Food diary

Individuals are supposed to maintain a food diary

Food intake (types & amounts) should be recorded

by the subject at the time of consumption.

Reliable but difficult to maintain.

The length of the collection period range between

1-7 days.

5. Observed food 5. Observed food consumptionconsumption

Not used for clinical practice, but it is recommended

for research purposes.

The meal eaten by the individual is weighed and

contents are exactly calculated.

The method is characterized by having a high degree of

accuracy but expensive & needs time & efforts.

How to evaluate the diet?How to evaluate the diet?

Once the consumed amounts are assessed and Once the consumed amounts are assessed and calculated, it is evaluated whether they are deficient calculated, it is evaluated whether they are deficient or sufficient or are in excess.or sufficient or are in excess.

Calculate the calorie count and amount of nutrients in the individual’s diet….e.g. chart for vegetables

1. Quantifying the nutrients

Calculate the nutrient requirement for age, sex, physical activity level

Calorie Intake as proportions of nutrients….

2. Qualitative assessment - Nutrient pyramid….

Diet correctionDiet correction

Correction of the dietary practices can then be done Correction of the dietary practices can then be done depending on the discrepancy between the intake and depending on the discrepancy between the intake and actual requirement.actual requirement.

Hygienic food preparation, food additives, methods of Hygienic food preparation, food additives, methods of preparation (e.g. how the nutritional value differs on the preparation (e.g. how the nutritional value differs on the fact whether the fish is consumed raw, grilled or fried) fact whether the fish is consumed raw, grilled or fried) should also be advised on.should also be advised on.

Importance of timely food consumption, varying the diet Importance of timely food consumption, varying the diet in quantity and quality according to the age, sex, in quantity and quality according to the age, sex, physiological status, co-morbidities, level of activity etc. physiological status, co-morbidities, level of activity etc. are stressed.are stressed.

Reference: Assessment of nutritional status. Reference: Assessment of nutritional status. Abdelaziz Elamin, MD, PhD, FRCPCHAbdelaziz Elamin, MD, PhD, FRCPCH College of MedicineCollege of Medicine Sultan Qaboos University, OmanSultan Qaboos University, Oman

Thank you!Thank you!