EAL

NNNS: Adverse Effects (2011)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

To examine and compare the effects of aspartame- and sugar-sweetened beverages on mood states of normal adult women.

Inclusion Criteria:

Young college women
18 to 30 years of age.

Exclusion Criteria:

Not pregnant
Not lactating
Not diabetic
Not taking any medication known to affect appetite or mood.

Description of Study Protocol:

Recruitment

Subjects were students recruited from a large introductory nutrition course.

Design

Non-randomized crossover trial, William's square design.

Blinding Used

Subjects were told that the purpose of the study was to compare the effects of commonly used food additives on their moods and appetite, but were not told that the food additives were sugar and aspartame.

Intervention

Subjects received, on three different occasions, either 12 ounces of water, aspartame-sweetened beverage or sugar-sweetened beverage, separated by weekly intervals.

Statistical Analysis

A univariate procedure was performed on the Stanford Sleepiness Scale responses and the Visual Analog Mood Scale and Profile of Mood States principal components to test for normality. A one-way ANOVA procedure was then performed and comparisons were made using least significant differences tests.

Data Collection Summary:

Timing of Measurements

Anthropometric measurements taken during first study week. Subjects received three different drinks on three different occasions, separated by weekly intervals. Changes in mood were assessed by administering test questionnaires before and one hour after the beverages were drunk.

Dependent Variables

Stanford Sleepiness Scale
Visual Analog Mood Scale
Profile of Mood States
Height without shoes
Weight in light clothing with Detecto sliding weight balance scale
Triceps, suprailiac and abdominal skinfold thicknesses measured with Lange skinfold calipers.

Independent Variables

12 ounces of water, aspartame-sweetened beverage (180mg to 280mg aspartame) or sugar-sweetened beverage (50g sucrose)
One week washout between test days.

Description of Actual Data Sample:

Initial N: 120 young women
Attrition (final N): 120 women
Age: Mean age, 20.0±0.2 years
Ethnicity: Not mentioned
Other relevant demographics: Mean body fat percentage, 25.3±0.5
Location: Kansas State University.

Summary of Results:

Other Findings

Changes in mood were similar following consumption of water or the aspartame-sweetened beverage
However, the ingestion of the sugar-sweetened beverage was followed by increased sleepiness during the last half-hour of the one-hour observation period (P<0.002). The effect was observed as early as 30 minutes post-ingestion (P<0.02) and continued throughout the one-hour observation period (P<0.005).
Other mood states assessed by the VAMS and POMS tests were not significantly different when responses to the three beverages were compared.

Author Conclusion:

In our study, sleepiness was induced in young women after ingestion of a sucrose-containing beverage in the afternoon hours. The aspartame-sweetened beverage did not affect any of the mood states tested in our study.

Funding Source:

University/Hospital:

Monell Chemical Senses Center, Kansas State University

Reviewer Comments:

Validated measures of mood.

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?		N/A
	3.1.	Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)	N/A
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	N/A
	3.3.	Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.)	N/A
	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?	N/A
	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?		No
	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.)	No
	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?	???
	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)?	N/A
	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