EAL

AWM: Eating Frequency and Patterns (2013)

Citation:

Schusdziarra V, Hausmann M, Wittke C, Mittermeier J, Kellner M, Wagenpfeil S, Erdmann J. Contribution of energy density and food quantity to short-term fluctuations of energy intake in normal weight and obese subjects. Eur J Nutr 2010; 49 (1): 37-43.

PubMed ID: 19669825

Study Design:

Case Control Study

Class:

C - Click here for explanation of classification scheme.

Quality Rating:

NEUTRAL: See Quality Criteria Checklist below.

Research Purpose:

To obtain more detailed information about day-to-day variations of food intake food diaries recorded during 10 consecutive days of 280 obese and 100 normal weight subjects were examined.

Inclusion Criteria:

Overweight patients who had contacted the outpatient clinic of the department of nutritional medicine for treatment of their weight problem in 2005-2006
Had a history of attempting various diets for weight loss
Had maintained their weight for at least 12 months without any period of intentional or spontaneous weight loss
Normal weight patients were recruited and selected according to age and gender to match the obese group as much as possible.

Exclusion Criteria:

None noted.

Description of Study Protocol:

Recruitment

Overweight/obese patients had contacted the outpatient clinic of the department of nutritional medicine fro treatment of their weight problem
Normal weight patients were recruited by advertisement and selection was made according to age and gender to match the obese group as much as possible.

Design

Case-control study

Blinding used

Not used

Intervention

Patients completed a food diary over 10 consecutive days prior to the start of therapy. They were to record every item they ate or drank, the time they consumed it, the amount they ate and how the food was prepared. All patients (including normal weight) were handed a booklet with examples of characteristic portion sizes in case of eating out.

Statistical Analysis

Dietary protocols were calculated with the program PRODI 4.5 Expert
Calculation of the coefficient of variation (CV) of each individual's food intake, the mean ± SD was calculated for the 10 days and SD divided by the mean value times 100 gave the CV
To assess individual day-to-day fluctuations of food intake with greater transparency for the entire group data were ranked according to daily energy intake
T test for paired or unpaired data were used, where appropriate correction for multiple testing was made according to Bonferroni-Holm
P values of 0.05 or less were considered significant
Analyzed by using SPSS (version 11.5).

Data Collection Summary:

Timing of Measurements

10 consecutive days

Dependent Variables

Subjects completed a food diary over 10 consecutive days prior to the start of therapy and diets were analyzed (using the PRODI 4.5 expert program to calculate dietary protocols) based on the following:

Energy density
Food quantity
Energy intake.

Independent Variables

Obese vs. normal weight

Control Variables

Description of Actual Data Sample:

Initial N: 380 subjects
- 280 obese and 100 normal weight
- 272 female and 108 male
Attrition (final N): 380 subjects
- 280 obese and 100 normal weight
- 272 female and 108 male
Age:
- Obese group: Mean age 45±11.5 years
- Normal weight group: mean age 42±8.7 years
Ethnicity: Not described
Other relevant demographics:
Anthropometrics:
- Body weight of obese group: 108±25.9kg; body weight of normal weight group: 67±7.3kg
- BMI of obese group: 36.6±8.8; BMI of normal weight group: 22.5±1.9
Location: Germany.

Summary of Results:

Key Findings

Food Intake Data Based on the 10-day Recording Period of Obese and Normal Weight Subjects and Coefficient of Variation

Variable	Obese Group n=280	Normal Weight Group n=100
Food quantity (grams per day)	1,087±390	1,071±370
Total energy intake (kcal per day)	2,024±705	2,055±667
Solid food energy intake (kcal per day)	1,668±642	1,778±598*
Liquid energy intake (kcal per day)	356±287	277±282
Energy density (kcal per day)	1.59±0.47	1.72±0.46*
Coefficient of variation (percent) Quantity Energy Energy density	24.3±8.6 23.8±8.8 22.1±7.4	23.7±9.0 23.6±9.0 20.6±6.6

*P<0.05 or less between groups

Food quantity and total energy intake was not different
Solid food energy intake and energy density was significantly lower in obese subjects
Little day-to-day difference of mean values of all three parameters in both groups.

Daily energy intake, food quantity and energy density on the basis of a ranking of each individual’s minimum to maximum daily energy intake (mean ± SEM)

Ranked Days

Obese Subjects
n=280

Normal Weight Subjects
n=100

Energy (kcal)

Quantity (g)

Energy density (kcal/g)

Energy (kcal)

Quantity (g)

Energy density (kcal/g)

R1 All meals without snacks

1,089±23.4

968±20.4^b

838±20.2

755±17.9^b

1.40±0.03

1.39±0.03

1,166±42.0

945±35.0^b

803±31.36

55±26.9^b

1.54±0.05

1.55±0.06

R2 All meals without snacks

1,263±23.7*^,a

1,105±19.7*^,a,b

924±19.5*^,a

814±17.2*^,a,b

1.45±0.03

1.44±0.03

1,371±40.3*^,a

1,099±38.7*^,a,b

944±34.0*^,a

777±31.5*^,a,b

1.53±0.04

1.51±0.04

R3 All meals without snacks

1,391±26.0*^,a

1,206±22.1*^,a,b

982±19.4*^,a

866±17.1*^,a,b

1.49±0.03^a

1.47±0.03^a

1,506±43.1*^,a

1,170±39.4^a,b

938±31.7^a

739±26.8^a,b

1.69±0.05*^,a

1.66±0.04*

R4 All meals without snacks

1,497±27.7^*,a

1,287±25.1*^a,b

1,031±21.0^*,a

908±18.1^*,a,b

1.52±0.03^a

1.49±0.03^a,b

1,613±43.8^*,a

1,255±39.1^*,a,b

1,023±34.6^*,a

824±29.1^*,a,b

1.66±0.04

1.58±0.04^b

R5 All meals without snacks

1,603±29.6^*,a

1,366±25.7^*,a,b

1,055±20.3^a

927±18.1^a,b

1.60±0.03^*,a

1.55±0.03^*,a,b

1,707±43.9^*,a

1,303±39.0^a,b

1,068±30.4^a

861±28.5^a,b

1.66±0.04

1.58±0.04^b

R6 All meals without snacks

1,700±30.7^*,a

1,462±26.9^*,a,b

1,104±22.6^*,a

968±19.2^*,a,b

1.62±0.03^a

1.59±0.03^a,b

1,799±44.3^*,a

1,409±43.1^*,a,b

1,091±33.0^a

887±29.8^a,b

1.72±0.04^a

1.65±0.04^b

R7 All meals without snacks

1,805±32.0^*,a

1,500±27.0^*,a,b

1,142±21.7^*,a

987±18.4^a,b

1.65±0.03^a

1.59±0.03^a,b

1,909±45.6^*,a

1,461±44.5^a,b

1,126±36.3^a

887±33.1^a,b

1.78±0.04^a

1.76±0.05^*,a

R8 All meals without snacks

1,925±35.2^*,a

1,619±31.7^*,a,b

1,203±21.9^*,a

1,047±20.0^*,a,b

1.65±0.02^a

1.60±0.03^a,b

2,040±49.7^*,a

1,596±52.3^*,a,b

1,176±35.8^a

939±33.0^a,b

1.81±0.05^a

1.76±0.05^a,b

R9 All meals without snacks

2,077±38.9^*,a

1,711±32.1^*,a,b

1,242±24.3^a

1,059±20.6^a,b

1.75±0.03^*,a

1.69±0.03^*,a,b

2,187±50.2^*,a

1,652±52.0^a,b

1,205±32.6^a

962±31.7^a,b

1.89±0.05^a

1.78±0.05^a,b

R10 All meals without snacks

2,325±44.5^*,a

1,902±36.4^*,a,b

1,346±25.3^*,a

1,145±2.4^*,a,b

1.79±0.03^a

1.73±0.03^a,b

2,482±62.7^*,a

1,883±61.7^*,a,b

1,336±40.7^*,a

1,045±34.4^*,a,b

1.94±0.05^a

1.87±0.05^a,b

Significant difference of P<0.05 or less *vs. the preceding day

^avs. day r1

^bof all meals vs. without snacks

Mean energy intake varies over a wide range of 1,200-1,300kcal per day between the lowest and highest intake in both groups
As expected by definition energy intake of ranked days was significantly higher compared to the immediately preceding day
In contrast to the obese group food quantity in normal weight subjects was not significantly different from the preceding day except for days r2, r4 and r10
Compared to day r1 energy intake and food quantity were significantly higher from day r2 onwards in both groups while for energy density significant differences began on day r3 in the obese and on day r6 in normal weight subjects
Approximately two-thirds of acute increases of energy intake can be explained by a greater daily food quantity while one-third can be explained to a greater energy density of consumed food items
Snacks contribute significantly by 10-25% to food quantity and energy intake in normal weight and obese subjects
In the obese group the contribution of snacks to daily meal size and energy intake was less than in the normal weight subjects.

Other Findings

The number of snacks is directly related to daily food and energy intake in both groups indicating that snack consumption is not compensated by reduced food intake during main meals
Snacks only account for a small part of the day-to-day variations of food intake while the major changes are due to differences of the main meals.

Author Conclusion:

The present study demonstrates for the first time a substantial day-to-day variation of food and energy intake in obese subjects and confirms previously published data of day-to-day variations of energy intake in normal weight subjects
Differences of daily energy intake can be due to 1) different quantities of food during single meals; 2) differences of energy density of ingested food items; and 3) differences in the number of meals ingested per day
Analysis of the eating habits of these free-living populations confirms the role of energy density as one important determinant of energy intake but it also demonstrates that during short-term changes of energy intake, meal size plays an even greater role in both obese and normal weight subjects.

Funding Source:

Other:

Not reported

Reviewer Comments:

Large number of subjects in each group. Other similarities and differences between obese and normal weight groups not described.

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?		No
	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?	No
	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.)	???
	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.)	???
	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?	???
	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?	N/A
	6.2.	In observational study, were interventions, study settings, and clinicians/provider described?	Yes
	6.3.	Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?	N/A
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	N/A
	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?	N/A
	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)?	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?		???
	10.1.	Were sources of funding and investigators' affiliations described?	No
	10.2.	Was the study free from apparent conflict of interest?	???