EAL

NNNS: Polyols (2010)

Citation:

Study Design:

Class:

- Click here for explanation of classification scheme.

Quality Rating:

Research Purpose:

To determine whether there were differences between different polyols (sugar alcohols), in terms of their ability to stimulate intolerance symptoms, when consumed in milk chocolate
Also to discover whether symptomatology can be related to the dose of polyol ingested.

Inclusion Criteria:

No history of either gastrointestinal or metabolic disease and were not subject to any dietary restrictions, prescribed diets or supplementary fibre intake
Had not received antibiotics, steroids, laxatives or any other drugs for one month prior to the study (exception: oral contraceptives)
No previous adaptation to the test materials.

Exclusion Criteria:

None listed.

Description of Study Protocol:

Recruitment

Random recruitment from the student population of The University of Salford.

Design

Randomized, double-blind cross-over
Each product was given in random order, determined by a latin square design, applied to each leg of the cross-over study.

Blinding Used

Double-blind.

Intervention

Sucrose (40g; S)
Lactitol (40g; L)
Isomalt (40g; I)
Maltitol (40g; M)
10g sucrose plus 30g of either lactitol, isomalt or maltitol (SL, SI, SM)
30 subjects were assigned to one group in which S, SM, M and SL were consumed during Weeks One through Four and L, SI and I during Weeks Five through Seven
The other group of 29 subjects first consumed L, SI and I before crossing over to S, SM, M and SL
Consumption days were separated by periods of one week.

Statistical Analysis

Subjects' responses relating to symptomatology were categorical (Yes or No) and thus intolerance data were treated as non-parametric
Products were compared by contingency table analysis using 2x2 and 4x4 transition tables and analyzed by chi-square
The first method used the formula of McNemar (1947) to test for any difference between products without taking into account product order. The second method, as described by Gart (1969), tested for both product differences and product order. The final method uses 4x4 transition table analysis to take account of severity of symptomatology reported.
Differences in motion frequency between subjects during the test periods were assumed to be parametric and, following ANOVA, were analyzed by paired T-tests.

Data Collection Summary:

Timing of Measurements

Eight-week crossover study, with crossover occurring after Week Four
Consumption days were separated by periods of one week
The test product was consumed within a 30-minute period as breakfast
On the day following consumption of each product, subjects were individually debriefed according to a set protocol to determine if they had adhered to dietary restrictions and consumption regime. They were then questioned on their recorded gastrointestinal symptomatology as well as sensorial and textural data, the latter being included as distracter questions.

Dependent Variables

Gastrointestinal symptoms: Each subject was provided with printed sheets on which to record the incidence and severity of gastrointestinal symptoms and laxation for the 24-hour period following consumption of each product
Borborygms (rumbling noises)
Colic (abdominal pain)
Flatus (wind)
Each symptom was was ranked on a hedonic scale where Zero indicated normal function, One indicated mild symptoms, Two indicated moderate symptoms and Three indicated severe symptoms
Number of toilet visits and fecal consistency (watery, normal or hard) was also recorded.

Independent Variables

Test products were identical except for their added carbohydrate content and were manufactured at the ZDS confectionery school as 100g bars of milk chocolate with identical appearance and packaging
Each 100g bar contained 40g bulk sweetener as:
- Sucrose (S)
- Lactitol (L)
- Isomalt (I)
- Maltitol (M)
Mixture of of sucrose and polyol (10:30 w/w):
- Sucrose and lactitol (SL)
- Sucrose and maltitol (SM).
Sweetness levels were not adapted by addition of intense sweetener
Bars had identical wrappers, distinguished by codes which were not revealed to the investigators until after the completion of the study.

Control Variables

None listed.

Description of Actual Data Sample:

Initial N

60 subjects were recruited.

Attrition (Final N)

59 subjects completed the study (30 males; 29 females)
One subject reported the prescription of antibiotics following an attack of influenza and was thus excluded from the study.

Age

18-24 years old.

Ethnicity

Not given.

Other Relevant Demographics

College students.

Anthropometrics

BMI, males: 22.49±2.69
BMI, females: 21.85±2.09.

Location

The University of Salford.

Summary of Results:

Key Findings

The Gart exact test demonstrated that the order of product consumption had no significant effect on symptomatology for all products
The McNemar and Gart tests revealed that there were significant differences in both the incidence and severity of intolerance symptoms between the sugar-containing product and the polyol-containing products, as well as between the various polyol-containing products themselves
The greatest symptomatology occurred with the lactitol-containing chocolate, effects being greater with 40g versus 30g. Significantly greater incidence of borborygms, colic, flatus and laxation, compared with the control product (P<0.01). There was also a significant increase in the severity of symptoms (P<0.01).
Consumption of chocolate containing isomalt was also associated with an increase in the incidence and, in some cases, the severity of symptoms, compared with the control
The incidence and severity of symptoms were significantly less with maltitol
Both maltitol and isomalt appear to be superior to lactitol with regard to tolerance at the doses used in this study
It was apparent that, irrespective of severity, when symptoms did occur they tended to occur in the same individuals and this grouping of symptoms was significant at the 1% level
The Mean Total Symptom Score (MSS) was correlated with the dose of polyol ingested. The MSS increased significantly following consumption of 40g lactitol, compared with chocolate containing 40g maltitol and 30g of either isomalt or maltitol (P<0.01).
The fact that more subjects experienced multiple symptoms after consumption of any of the polyols compared to sucrose (P<0.01) suggests that some individuals were more susceptible to the osmotic effect of unabsorbed polyol in the small intestine and the continuing effect on entry into the large intestine along with unabsorbed hydrolysates.

Author Conclusion:

This work has shown that there are significant differences in the reporting of gastrointestinal symptomatology following the consumption of isomalt, lactitol and maltitol incorporated into milk chocolate
However, with all three polyols, the incidence and severity of symptomatology was dose-dependent.

Funding Source:

Industry:

Roquette Freres

Food Company:

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?	???
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?	???
	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?	Yes
	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.)	N/A
	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?	N/A
	6.6.	Were extra or unplanned treatments described?	N/A
	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)?	???
	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