EAL

UM: Umami Compounds and Palatability (2013)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

The objective of this study was to determine whether the addition of flavor enhancers to the cooked meals over 16 weeks would lead to an increase in food consumption and thereby provide nutritional benefits to elderly nursing home residents.

Inclusion Criteria:

Older than 65 years of age
No known dementia or residing in a somatic ward
No known depression
No disease in terminal phase
No allergy to monosodium glutamate (MSG)
Residing in a nursing home for more than three months
Consuming the cooked meal provided by the nursing home kitchen at lunchtime at least five days per week.

Exclusion Criteria:

Not described.

Description of Study Protocol:

Recruitment: Subjects were recruited from the nursing home "Rustenburg" in the Netherlands
Design: Randomized controlled trial
Blinding used: Implied with measurements
Intervention: A parallel group intervention was applied. The intervention consisted of adding flavor enhancers to the main dish of cooked meals of the flavor group, but not to the meals of the control group.

Statistical Analysis

Means plus or minus standard deviations (SD) of baseline and absolute changes were calculated for the outcome variables per group
Changes were compared with an unpaired T-test for differences between groups or with a paired T-test for differences within groups
A P-value of up to 0.05 was considered statistically significant
Data were analyzed using SAS.

Data Collection Summary:

Timing of Measurements

Measurements taken before and after eight and 16 weeks of intervention.

Dependent Variables

Food consumption plus nutritional benefits
- Total dietary intake was collected using a combination of a three-day record and weighing back methods before and at the end of the intervention
- Bread-based meal, snack and beverage consumption was recorded in individual food diaries and checked by interviews with a trained dietitian
- Portion sizes were derived from a Dutch table
- Dietary intake at the cooked meal was assessed with a three-day weighing back method before the intervention.
Patient's body weight as an index of nutritional status before and after the study was measured before breakfast and after voiding to the nearest 0.5kg (Seca weighing scale)
The knee-to-floor height (KFH) was measured twice by a single trained observer with a stadiometer in a sitting position, from the anterior surface of the thigh to the floor with the ankle and the knee flexed at a 90-degree angle against the metallic help
Subjects responded to a 29-item questionnaire about their feeling of hunger appetite and their taste and smell perception
The geriatric depression scale (GDS) used to assess the depression status of the subjects consisted of 15 items to be answered yes or no. The answers of each participant were summed to obtain a score with each score above five indicating a depressive status.

Independent Variables

The intervention consisted of adding flavor enhancers to the main dish of cooked meals of the flavor group, but not to the meals of the control group.

Description of Actual Data Sample:

Initial N: 71 subjects

Attrition (final N): 67 subjects, 31 in the control group (6 male, 25 female) and 36 in the flavor group (7 male, 29 female)

Age: Mean age in the control group was 83 years, mean age in the flavor group was 84.6 years

Ethnicity: Dutch

Other relevant demographics: Not reported

Anthropometrics: Resident characteristics were similar for both groups at the start of the study

Location: The Netherlands

Summary of Results:

Key Findings

On average, the body weight of the flavor group increased (+1.1±1.3kg, P<0.05) compared with that of the control group (-0.3±1.6kg, P<0.05)
Daily dietary intake decreased in the control group (-485±1,245kJ, P<0.05), but not in the flavor group (-208±1,115kJ, P=0.28)
Intake of the cooked meal increased in the flavor group (133±367kJ, P<0.05), but not in the control group (85±392kJ)
A similar trend was observed for hunger feelings which increased only in the flavor group.

Author Conclusion:

Adding flavor enhancers to the cooked meals was an effective way to improve dietary intake and body weight in elderly nursing home residents.

Funding Source:

University/Hospital:

Wageningen University, The Netherlands

Reviewer Comments:

Quality Criteria Checklist: Primary Research
Relevance Questions
	1.	Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies)	Yes
	2.	Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?	Yes
	3.	Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice?	Yes
	4.	Is the intervention or procedure feasible? (NA for some epidemiological studies)	Yes

Validity Questions
1.	Was the research question clearly stated?		Yes
	1.1.	Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?	Yes
	1.2.	Was (were) the outcome(s) [dependent variable(s)] clearly indicated?	Yes
	1.3.	Were the target population and setting specified?	Yes
2.	Was the selection of study subjects/patients free from bias?		Yes
	2.1.	Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?	Yes
	2.2.	Were criteria applied equally to all study groups?	Yes
	2.3.	Were health, demographics, and other characteristics of subjects described?	Yes
	2.4.	Were the subjects/patients a representative sample of the relevant population?	Yes
3.	Were study groups comparable?		Yes
	3.1.	Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)	Yes
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	Yes
	3.3.	Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.)	Yes
	3.4.	If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis?	N/A
	3.5.	If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.)	N/A
	3.6.	If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")?	N/A
4.	Was method of handling withdrawals described?		Yes
	4.1.	Were follow-up methods described and the same for all groups?	Yes
	4.2.	Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.)	Yes
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	Yes
	4.4.	Were reasons for withdrawals similar across groups?	Yes
	4.5.	If diagnostic test, was decision to perform reference test not dependent on results of test under study?	N/A
5.	Was blinding used to prevent introduction of bias?		Yes
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	No
	5.2.	Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.)	Yes
	5.3.	In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?	N/A
	5.4.	In case control study, was case definition explicit and case ascertainment not influenced by exposure status?	N/A
	5.5.	In diagnostic study, were test results blinded to patient history and other test results?	N/A
6.	Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described?		Yes
	6.1.	In RCT or other intervention trial, were protocols described for all regimens studied?	Yes
	6.2.	In observational study, were interventions, study settings, and clinicians/provider described?	N/A
	6.3.	Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?	Yes
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	Yes
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	Yes
	6.6.	Were extra or unplanned treatments described?	Yes
	6.7.	Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?	Yes
	6.8.	In diagnostic study, were details of test administration and replication sufficient?	N/A
7.	Were outcomes clearly defined and the measurements valid and reliable?		Yes
	7.1.	Were primary and secondary endpoints described and relevant to the question?	Yes
	7.2.	Were nutrition measures appropriate to question and outcomes of concern?	Yes
	7.3.	Was the period of follow-up long enough for important outcome(s) to occur?	Yes
	7.4.	Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?	Yes
	7.5.	Was the measurement of effect at an appropriate level of precision?	Yes
	7.6.	Were other factors accounted for (measured) that could affect outcomes?	Yes
	7.7.	Were the measurements conducted consistently across groups?	Yes
8.	Was the statistical analysis appropriate for the study design and type of outcome indicators?		Yes
	8.1.	Were statistical analyses adequately described and the results reported appropriately?	Yes
	8.2.	Were correct statistical tests used and assumptions of test not violated?	Yes
	8.3.	Were statistics reported with levels of significance and/or confidence intervals?	Yes
	8.4.	Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)?	N/A
	8.5.	Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)?	???
	8.6.	Was clinical significance as well as statistical significance reported?	Yes
	8.7.	If negative findings, was a power calculation reported to address type 2 error?	N/A
9.	Are conclusions supported by results with biases and limitations taken into consideration?		Yes
	9.1.	Is there a discussion of findings?	Yes
	9.2.	Are biases and study limitations identified and discussed?	Yes
10.	Is bias due to study's funding or sponsorship unlikely?		Yes
	10.1.	Were sources of funding and investigators' affiliations described?	Yes
	10.2.	Was the study free from apparent conflict of interest?	Yes