NUTRITION RESEARCH
METHODOLOGIES
HNH24306
,Week 1 you do not have to learn this part
Learning goals:
Understand quality aspects of a nutrition intervention (week 6)
Choose appropriate methods to measure body composition, PA, dietary intake or nutrient
status in a given situation (week 2-5)
Critically comment on methodological choices in published scientific literature (2-7)
Week 2
Dietary assessment
Dietary assessment methods can be used for different purposes:
- Epidemiological studies (research)
- Experimental/Clinical trials (research)
- Surveillance and monitoring (research)
- Dietary advice (patient care)
Problems and aims of dietary assessment
Diet is complex to measure preparation, novel foods and supplements, variation in intake,
age groups, characteristics and estimation portion size
Can you identify all ingredients? Do you know all amounts within 5 grams accuracy? Was this
meal representative for your evening meal?
Essentials for each dietary assessment
Reference period: previous month, today
Portion sizes: weighing foods, household measures
Food composition table: local tables? Recent table? Specific component available?
How can you do dietary assessment?
Self-reports or markers of exposure (biomarker)
Self-reports:
- 24-hour dietary recall
1
, - Food record or food diary (observation, duplicate portion)
- Food frequency questionnaire
- Diet history
24-hour dietary recall
Recall of past 24-hours, interview. Can be on the telephone or face-to-face. You tell
everything about the last 24 hours. Very popular, it is very easy and has less errors than the
FFQ.
Disadvantages: day-to-day variation and response errors
Food records/diary
Record current intake, amount and time eaten. It is a prospective method. Creates
awareness of intake.
Disadvantages: People become aware of what they eat, and they change their intake.
Burdensome (weighing)
The collection of the food consumption data for two days.
Dietary history method
The interviewer is asking the long term/usual intake of the patient. It can last for almost two
hours in research. Meal-based, much detail.
Disadvantage: burdensome and experienced interviewers needed.
Food frequency questionnaire
Questionnaire about the usual/long term intake. Very easy and can be used in large
epidemiological trials.
Disadvantage: culturally based, difficult to recall past intake and no information on single
foods.
FFQ: Screeners (short questionnaires)
Short questionnaires tailored for qualitative assessment of diet
Fruits and vegetables, energy-% from fat, dietary patterns
Needed when very limited room for questions on diet
Useful in situations that do not require assessment of total diet
Estimated of intake are not as accurate as those from more detailed methods
Available methods – technology
Ebutton: wearable electronic device, containing sensors and data processing and storage
elements with miniature camera and microphone.
2
METHODOLOGIES
HNH24306
,Week 1 you do not have to learn this part
Learning goals:
Understand quality aspects of a nutrition intervention (week 6)
Choose appropriate methods to measure body composition, PA, dietary intake or nutrient
status in a given situation (week 2-5)
Critically comment on methodological choices in published scientific literature (2-7)
Week 2
Dietary assessment
Dietary assessment methods can be used for different purposes:
- Epidemiological studies (research)
- Experimental/Clinical trials (research)
- Surveillance and monitoring (research)
- Dietary advice (patient care)
Problems and aims of dietary assessment
Diet is complex to measure preparation, novel foods and supplements, variation in intake,
age groups, characteristics and estimation portion size
Can you identify all ingredients? Do you know all amounts within 5 grams accuracy? Was this
meal representative for your evening meal?
Essentials for each dietary assessment
Reference period: previous month, today
Portion sizes: weighing foods, household measures
Food composition table: local tables? Recent table? Specific component available?
How can you do dietary assessment?
Self-reports or markers of exposure (biomarker)
Self-reports:
- 24-hour dietary recall
1
, - Food record or food diary (observation, duplicate portion)
- Food frequency questionnaire
- Diet history
24-hour dietary recall
Recall of past 24-hours, interview. Can be on the telephone or face-to-face. You tell
everything about the last 24 hours. Very popular, it is very easy and has less errors than the
FFQ.
Disadvantages: day-to-day variation and response errors
Food records/diary
Record current intake, amount and time eaten. It is a prospective method. Creates
awareness of intake.
Disadvantages: People become aware of what they eat, and they change their intake.
Burdensome (weighing)
The collection of the food consumption data for two days.
Dietary history method
The interviewer is asking the long term/usual intake of the patient. It can last for almost two
hours in research. Meal-based, much detail.
Disadvantage: burdensome and experienced interviewers needed.
Food frequency questionnaire
Questionnaire about the usual/long term intake. Very easy and can be used in large
epidemiological trials.
Disadvantage: culturally based, difficult to recall past intake and no information on single
foods.
FFQ: Screeners (short questionnaires)
Short questionnaires tailored for qualitative assessment of diet
Fruits and vegetables, energy-% from fat, dietary patterns
Needed when very limited room for questions on diet
Useful in situations that do not require assessment of total diet
Estimated of intake are not as accurate as those from more detailed methods
Available methods – technology
Ebutton: wearable electronic device, containing sensors and data processing and storage
elements with miniature camera and microphone.
2
