Regular consumption of a cereal breakfast. Effects on mood and body image satisfaction in adult non-obese women

Appetite 55 (2010) 512–521

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Research report

Regular consumption of a cereal breakfast. Effects on mood and body image satisfaction in adult non-obese women§ Paul Lattimore a,*, Jenny Walton b, Sarah Bartlett a, Allan Hackett c, Leonard Stevenson c a

School of Natural Sciences & Psychology, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, UK Kelloggs Co. Ltd., Manchester, UK c Centre for Tourism, Consumer & Food Studies, Liverpool John Moores University, UK b

A R T I C L E I N F O

A B S T R A C T

Article history: Received 14 May 2010 Received in revised form 13 August 2010 Accepted 30 August 2010

Breakfast has psychological and nutritional benefits due to physiological mechanisms and expectations about health impact. Beliefs people hold about calories in food can adversely affect mood and bodyimage satisfaction and such adverse reactions can be predicted by body mass index. The objectives were to test the effect of consuming isocaloric breakfasts, appearing different in calorie content, on appetite, mood and body-image satisfaction, and to assess impact on daily nutrient intake. One-hundred-andtwenty-three women were randomly assigned to eat a cereal or muffin breakfast which ‘‘appeared’’ different in calorie content while unaware they were isocaloric. Participants estimated calories of breakfast, appetite, mood, and body-image satisfaction on a daily basis for seven-days. The cereal breakfast was perceived to be lower in calories, made participants fuller, happier, relaxed, and more satisfied about weight and body compared to the muffin breakfast. Differences in estimated daily fibre and micronutrient intake were compatible with the design. Breakfasts were isocaloric yet the cereal breakfast was rated lower in calories and produced more positive psychological reactions. This evidence indicates the power of perceptions of foods to influence important attributes of health and well-being which could be valuable in dietary interventions where mood and body image satisfaction affect outcome. ß 2010 Elsevier Ltd. All rights reserved.

Keywords: Breakfast Mood Body-image Nutrition Weight

Introduction Weight loss intervention studies highlight the importance of improved body image satisfaction as an outcome (Dalle Grave et al., 2007) and potential motivator of weight loss maintenance (Heinberg, Thompson, & Matzon, 2001; Palmeira et al., 2009). The current study focused on food intake, namely breakfast, as a determinant of body image satisfaction. Breakfast consumption has acute effects on mood (Lloyd, Rogers, & Hedderley, 1996). Regular consumption of breakfast is associated with a range of benefits, including: (1) better mental health in adults and

§ We thank the volunteers whose participation made the study possible. We gratefully acknowledge colleagues from Liverpool John Moores University: Katy Thompson-Lunt and Noora Kookarinen for assistance with data collection; Ted Sayers and Russell Schroeder for coordinating trial randomization; Liquid Solutions for the design and production work of breakfast diaries. The authors responsibilities were as follows—PL, SB: design of the experiment, collection of data, analysis of data, interpretation of results and writing of the manuscript; JW, AH and LS: design of the experiment, interpretation of results and writing of the manuscript. Funding for this research was provided by Kellogg’s UK. We are grateful to reviewers for suggested improvements to the manuscript submitted. * Corresponding author. E-mail address: [email protected] (P. Lattimore).

0195-6663/$ – see front matter ß 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.appet.2010.08.019

adolescents (O’Sullivan et al., 2008; Smith, 1998, 2002, 2005; Smith & Rees, 2000); (2) improved nutrition (Barton et al., 2005; de la Hunty & Ashwell, 2007); (3) success in weight loss (Lightowler & Henry, 2009) and (4) marked satiation, moderation of total energy intake throughout the day and healthier lifestyle behaviours (Cho, Dietrich, Brown, Clark, & Block, 2003; Clegg & Shafat, 2010; de la Hunty & Ashwell, 2007; Foster-Schubert et al., 2008; O’Sullivan et al., 2008). The putative physiological mechanisms underlying the benefits of breakfast consumption on mental state are complex (Benton, Brett, & Brain, 1987; Benton, Griffiths, & Haller, 1997; Benton, Haller, & Fordy, 1995; Hoyland, Dye, & Lawton, 2009; Hutto, 1997; Kaplan, Field, Crawford, & Simpson, 2007; Young, 2002). The focus of the current investigation relates to psychological effects of regular breakfast consumption in adults, particularly regarding mood. An issue that has not yet been considered but may partly explain the effect of breakfast on mood is the beliefs people hold about the potential health benefits of food they eat or their expectations of how meals may affect their mood, weight and by consequence body image satisfaction. The current investigation examined the acute effects of breakfast consumption on mood, body image satisfaction and appetite. Beliefs people hold about the calorie content of food determine mood immediately after eating which is coupled with changes in

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weight and body shape satisfaction (Fett, Lattimore, Roefs, Geschwind, & Jansen, 2009; Geschwind, Roefs, Lattimore, Fett, & Jansen, 2008; Thompson, Coovert, Pasman, & Robb, 1993; Vocks, Legenbauer, & Heil, 2007; Wardle & Foley, 1989). Women feel worse about their body shape and weight after exposure to highcalorie food cues (Fett et al., 2009; Geschwind et al., 2008). Similarly, after consuming a high-caloric milkshake, women felt worse about their body image (Vocks et al., 2007) and when told a high-caloric milkshake was high in calories they felt worse about their body image after consuming it than when they were told it was low in calories, even though milkshakes were isocaloric (Thompson et al., 1993). These laboratory-based investigations indicate that the effects of food intake or food cue exposure partly depend upon restrained eating patterns (Geschwind et al., 2008; Vocks et al., 2007; Wardle & Foley, 1989) or a combination of dietary restraint and body mass index (BMI) (Fett et al., 2009). These studies suggest that the expectations people have about the consequences for weight gain of consuming high-calorie ‘‘forbidden’’ foods may determine psychological reactions to consumption of such foods (Lattimore & Hutchinson, 2010; Thompson et al., 1993). This proposition is supported by an experience sampling investigation of women attempting weight loss. When women believed they were regularly eating a low-calorie evening meal they felt more relaxed, happier and more satisfied about their weight and shape immediately after eating than when they believed their meal was high in calories (Lattimore & Hutchinson, 2010); this outcome was partly explained by level of dietary restraint and BMI. This outcome highlights the importance of beliefs, however inaccurate, people hold about the energy content of food they consume and how this has a bearing on their experience of body image. The evidence from laboratory investigations about the effect of food intake on body image satisfaction is limited to highcalorie ‘‘forbidden’’ foods (Fett et al., 2009; Geschwind et al., 2008; Thompson et al., 1993; Vocks et al., 2007; Wardle & Foley, 1989) and an investigation that has only sampled eating behaviour in free-living conditions without manipulating actual intake (Lattimore & Hutchinson, 2010). To address these limitations, research should manipulate intake in free-living conditions by comparing isocaloric meals that ‘‘appear’’ markedly different in calorie content. The current investigation

513

addressed this issue using breakfast meals because of putative psychological and nutritional benefits (de la Hunty & Ashwell, 2007; O’Sullivan et al., 2008; Smith, 1998). Women were randomly allocated to consume either a cereal or muffin breakfast in their own homes for seven days without knowing that meals were matched for energy. The cereal breakfast comprised a portion of cereal, toast and apple juice. We expected that it would appear lower in calories than the muffin breakfast which comprised one chocolate-chip muffin and apple juice. Participant’s received the foodstuffs in manufacturers packaging which displayed nutritional labels. Participants provided ratings of perceived calories of meals, mood, appetite and body image immediately after consuming their meals. We predicted that participants would believe the cereal breakfast to be lower in calories than the muffin breakfast and that consuming the cereal breakfast would be related to better mood, weight and shape satisfaction relative to consuming the muffin breakfast. Previously, better weight and body shape satisfaction has been associated with beliefs about calorie content of evening meals in those attempting weight loss (Lattimore & Hutchinson, 2010). In the current study we did not provide an evening meal but simply required participants to provide ratings immediately after their meal. We expected to find differences between breakfast and evening meal ratings. Related studies have shown that the effect of food intake on state body image satisfaction can partly been explained by trait level body image satisfaction, dietary restraint and BMI. We incorporated such measures to determine their influence on outcomes. Additionally, we investigated whether consumption of either breakfast would influence patterns of daily nutrient intake over a period of a week. Methods Design A between-subjects randomised design was employed to allocate participants to either a cereal breakfast or muffin breakfast condition. Mood, hunger, fullness, and weight and body satisfaction were assessed on a daily basis for one week immediately after consumption of breakfast. Measures of eating attitudes, mood, self-

Table 1 The psychological and physical characteristics of participants at baseline. Measures (scale)

Breakfast condition Cereal (n = 59)

Age (y) Body weight (kg) Height (cm) BMI (kg/m2) Uncontrolled eating (0–100)b Cognitive restraint (0–100)c Emotional eating (0–100)d Anxiety (0–21)e Depression (0–21)f Weight/shape concerns (16–80)g Self-esteem (10–40)h

Muffin (n = 64)

M

SEM

M

SEM

pa

28.9 65.6 163.5 24.5 36.0 39.6 26.6 3.6 2.0 38.3 34.2

0.9 1.3 0.8 0.4 3.0 2.6 3.1 0.3 0.3 2.0 0.7

29.4 65.8 164.6 24.2 38.3 41.2 33.9 4.6 1.9 40.7 32.5

0.8 1.3 0.9 0.4 2.4 2.6 2.9 0.3 0.3 1.7 0.6

0.65 0.92 0.36 0.68 0.55 0.65 0.09 0.02 0.84 0.35 0.05

Notes: a p values are not significant as they are greater than a required for critical t calculated using Holm’s multi-stage Bonferroni’s correction to control for inflation of a (critical t = 2.87, a = 0.05, c = 11, df = 121). b TFEQ uncontrolled eating scale. c TFEQ cognitive restraint scale. d TFEQ emotional eating scale. e HADS anxiety scale. f HADS depression scale. g BSQ-16 weight and shape concerns scale. h Rosenberg self-esteem scale.

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514

esteem, weight concerns, shape concerns, and estimated nutrient intake were assessed at baseline and on completion. Participants One-hundred-and-twenty-three female participants completed the study. The employment status of participants in the cereal breakfast condition was 60% employed 19% unemployed and 20% in full-time higher education. In the muffin breakfast condition there were 61% employed, 15% unemployed and 24% in full-time higher education. In the cereal breakfast condition 92% described themselves as ‘White British, English, Irish, Scottish or Welsh’; in the muffin breakfast condition 95% identified themselves as ‘White British, English, Irish, Scottish or Welsh’. The age, weight, height,

[(Fig._1)TD$IG]

BMI, and psychological characteristics of participants in both conditions are displayed in Table 1. Recruitment and selection protocol: The third author recruited participants through advertisements in local newspapers inviting people to take part in research about ‘‘breakfast cereals and appetite’’. An overview of the recruitment protocol and timeline of the study is displayed in Fig. 1. Participants (n = 370) who responded to the adverts were interviewed by telephone (n = 283) to determine their eligibility (87 could not be reached). Participants were required to be female, 20–40 years old and to have a BMI between 19.5 and 29.5 kg/m2. Those with a BMI above 30 were excluded because comorbidities associated with being clinically obese may have unduly distorted outcomes. Participants were excluded if they: had food allergies or gluten intolerance; had a current or past history of an

Response to media advertisment n=370

Telephone interviews inclusion/exclusion criteria N = 283

Eligible

Not eligible

N = 192

N = 91

Baseline assessment FFQ, TFEQ, BSQ-16, HADS, RSE, weight & height N = 129

Random allocation

Cereal breakfast

Muffin breakfast

N = 63

N = 66

Breakfast & Diary 7 days

Breakfast & Diary 7 days

Follow-up assessment

Follow-up assessment

Diary, FFQ & weight N = 59

Diary, FFQ & weight N = 64

Fig. 1. Recruitment, allocation and assessment protocol overview.

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eating or other mental health disorder; were currently pregnant or recently had given birth; had diabetes; were currently using prescribed anti-depressant or weight loss medication; were taking part in a national health service or commercial weight loss intervention; were currently experiencing low mood and/or low self-esteem (assessed using two items from the Hospital Anxiety and Depression Scale and the Rosenberg Self-Esteem Scale; see ‘Measures’ section). Those who met the inclusion criteria (n = 192) were invited to attend for baseline assessments. Those who attended (n = 129) were randomly allocated to eat either the cereal breakfast (n = 63) or muffin breakfast (n = 66) for one week. After one week participants (n = 126) returned for a follow-up assessment. Two attempts were made to contact the three noncompleters, one of whom was too unwell to attend follow-up; the other two could not be contacted. Due to systematic missing data on outcome measures the final number of participants included in the per-protocol analysis was 123. Measures Inclusion criteria assessment: Each of the exclusion criteria (see participants section) were assessed using simple questions with yes or no responses (details available upon request). Breakfasts: Participants were required to consume either a cereal or muffin based breakfast every day for seven days (see Table 2 for nutrition profile of breakfasts). The cereal breakfast (392 kcal) comprised a portion of breakfast cereal with semiskimmed milk, wholemeal bread toasted with low-fat spread, and pure apple juice. Sugar was not provided for the cereal and participants were instructed to consume the cereal without added sugar. The muffin breakfast (400 kcal) comprised one commercially produced chocolate-chip muffin and a pure apple juice. The apple juice is equivalent to one portion of fruit or vegetables. Baseline psychological measures weight and height: The Hospital Anxiety and Depression Scales (HADS) (Zigmond & Snaith, 1983) were used to assess mental well-being. The scale consists of seven depression and seven anxiety items. The 14 items are rated on 4point scales ranging from the absence of symptoms (zero) to maximum severity of symptoms (three). The Three-Factor Eating Questionnaire (TEFQ-R21) (Karlsson, Persson, Sjostrom, & Sullivan, 2000) was used to assess eating attitudes and comprises three scales that assess cognitive restraint (tendency to control food intake in order to influence body weight and shape) uncontrolled eating (tendency to lose control over eating when feeling hungry or in response to external food stimuli), and emotional eating

515

(propensity to overeat in relation to negative mood states). The TEFQ-R21 consists of 21 statements that are rated using a 4-point response scale (definitely true; mostly true; mostly false; and definitely false). Scores between one and four are summed to produce scale scores and the raw scores are transformed to a 0–100 scale. Higher scores are indicative of greater cognitive restraint, uncontrolled or emotional eating. The TEFQ-R21 has good internal consistency, criterion and discriminant validity (Karlsson et al., 2000). Weight and body shape concerns were assessed using the short form of the Body Shape Questionnaire (BSQ-16) (Evans & Dolan, 1993) which produces a score indicating the strength and salience of these concerns. Participants respond to 16 questions on a scale of one (never) to five (always) with higher scores reflecting greater concerns about body shape and weight. The scale has acceptable psychometric properties (Evans & Dolan, 1993). Selfesteem was measured using the Rosenberg Self-Esteem Scale (RSE) (Rosenberg, 1965) which is a 10-item self-report measure of global self-esteem consisting of statements related to overall feelings of self-worth or self-acceptance. Respondents indicate agreement or disagreement with each statement using 4-point scales ranging from strongly agree (1) to strongly disagree (4). The ratings assigned to all the items are summed after reverse scoring the positively worded items. Scores range from 10 to 40 with higher scores indicating higher self-esteem. Weight was measured using basic Tanita weighing scales (www.tanita.co.uk) and height was measured using a Seca portable Leicester height measure (www.seca.com) in everyday clothing with shoes removed. Main outcome measures: The main outcome measures were derived from ratings provided in a paper and pencil diary which was developed and tested in a previous study by the first author (Lattimore & Hutchinson, 2010). The diary was constructed so that participants followed a predefined order of completion each day: (1) ‘‘Record today’s date and time of completion’’; (2) ‘‘Record brief details of what you have eaten for breakfast and then place a vertical mark on the line below to indicate whether you think this meal was mostly low or high in calories’’ (Visual Analogue Scale (VAS): lowcalorie (0 mm) to high-calorie (100 mm); (3) ‘‘Think about the food you have just eaten for breakfast and how this has made you feel. Indicate on the vertical lines below to what extent the following statements apply to you at this moment’’. This statement was followed by six VAS, each preceded by the phrase ‘‘Right now, I feel. . .’’: not at all hungry (0 mm) to very hungry(100 mm); not at all happy (0 mm) to very happy (100 mm); not at all satisfied with my body (0 mm) to very satisfied with my body (100 mm); not at all full (0 mm) to very full (100 mm); not at all relaxed (0 mm) to very

Table 2 Serving size, energy and macronutrient content (g/ml) of breakfasts provided during the study. Portion, g/ml Cereal breakfast Cereala Semi-skimmed milk Wholemeal breadb Low-fat spreadc Apple juiced Total

30 150 36 5 200 –

Muffin breakfast Muffine Apple juiced Total

73 200 –

kcal

Protein

Cho

Sugar

487 314 340 110 395

115 75 80 27 95 392

3.9 5.4 4.0 0.0 0.2 13.5

22.8 7.2 14.1 0.0 22.2 66.3

6.9 7.2 1.4 0.0 22.2 37.7

1270 395

305 95 400

3.8 0.2 4.0

39.2 22.2 61.4

27.5 22.2 49.7

Kj

Notes: a Kellogg’s Special K Creamy Berry Crunch. b Tesco Stayfresh Wholemeal Medium sliced bread. c Tesco Enriched Low-Fat Sunflower Spread. d Tesco Apple Juice 200 ml carton with straw. e Tesco Chocolate-Chip Muffin (4-pack).

Fat

Sat. Fat

Fibre

Na

0.9 2.7 0.8 3.0 0.0 7.4

0.5 1.7 0.2 0.7 0.0 3.0

0.8 0.0 2.4 0.0 0.0 3.2

0.1 0.0 0.1 0.0 0.0 0.2

14.5 0.0 14.5

2.7 0.0 2.7

1.6 0.0 1.6

0.2 0.0 0.2

516

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relaxed (100 mm); and not at all satisfied with my weight (0 mm) to very satisfied with my weight (100 mm); (4) ‘‘Now send the following message using your mobile phone (predefined SMS message) to this number’’ (cell phone number). The SMS message was used to confirm date and time of completion (see procedure). Visual Analogue Scales have the advantage that they can be completed quickly creating improved sensitivity to small changes. They have been used reliably in studies of appetite (Stubbs et al., 2000) and mood and body image satisfaction (Heinberg & Thompson, 1995; Lattimore & Hutchinson, 2010). Secondary outcome measure: To investigate changes that may have occurred in eating patterns as a result of breakfast manipulations a validated Food Frequency Questionnaire (FFQ) was modified to estimate daily energy intake and its components. The FFQ was amended to assess participants’ recall of actual intake of a range of foods over the previous seven days. The semiquantitative FFQ included questions about a wide range of food items, comprising the major contributors to nutrient intakes within the UK diet. The FFQ was derived from one that has been validated by comparison with seven day weighed intake records (Burr et al., 1989; Fehily, Butland, Holliday, & Yarnell, 1988; Yarnell, Fehily, Milbank, Sweetnam, & Walker, 1983). Portion sizes were assigned to the foods recorded based on published average values (Crawley, 1994) and manufacturers’ data from 2005. The FFQ was devised using QBuilder software (Johns & Fehily, 1999) which incorporates algorithms to calculate estimated daily intake by reference to tables of food composition for use in the UK (Food Standards Agency, 2002; Holland et al., 1991). Estimated daily energy intake, and proportions of this as total fat, protein and carbohydrate were derived for analysis. The FFQ was administered at baseline to establish an estimate of nutrient intake from the previous seven days and again at the end of the seven-day sampling period to establish if changes had occurred. Procedure An overview of the recruitment process, completion rates and data collection points is displayed in Fig. 1. The study was conducted in North West England (UK) between March and June 2009. The ethical code of conduct of the British Psychological Society was followed. Participants provided informed consent and the research protocol was approved by the university research ethics committee. Payment of £30 in out of pocket expenses was provided to all who completed. Pre-allocation baseline assessments: Instructions about how to complete baseline assessments were provided to groups of participants by the first and third authors. Upon arrival at the research site participants were asked to complete the FFQ. To aid more accurate recall of what had been eaten in the past week, participants completed a free dietary recall task by recording in their own writing what they had eaten for breakfast, lunch, evening meal, snacks and drinks for as many of the past seven days as they could remember. They then used this information to complete the FFQ. The TEFQ-R21, BSQ-16, HADS and RSE measures were completed in that order and subsequently weight and height were measured. Randomization procedure: While baseline assessments were taking place a technical officer at the research site conducted the random allocation procedure which was concealed from researchers (SB & PL) and participants until after completion of baseline assessments. Unique participant identifiers were provided to a technical officer who had no knowledge of the nature of the experimental conditions. The officer was instructed to assign an allocation code to each unique participant identifier using a random number generator (http://www.randomization.com) to ensure a reasonably equal balance of allocations across the trial.

The randomization letter codes were sealed in envelopes with the unique identifier printed on the outside. PL and SB decoded the allocation codes and took the participants to separate rooms to inform them which breakfast they had been assigned to. Participants were not given any information about breakfasts prior to allocation. Instructions about breakfast menus: Instructions were provided about breakfast menus and a menu card was provided to remind participants of the portions they were to consume. In the cereal breakfast condition a demonstration was provided to explain how to measure a portion of cereal and milk and the amount of low-fat spread to use on toast. A disposable cup was used to measure cereal and milk portions which held 30 g of cereal or 150 ml of milk (previously calibrated in laboratory). Participants were provided with a cold storage bag (‘‘cool-bag’’) containing enough food items and measuring cups (cereal breakfast condition) for the following seven days and were given an appointment to return one week later. Semi-skimmed milk and muffins were purchased on each day of testing (ensuring at least 4–5 days before their use-by-date) and participants were instructed to store one pack of muffins in their home freezer to ensure the product could be eaten fresh upon defrosting. Participants started their trial the day after baseline assessments and always on a Monday, Tuesday, Wednesday or Thursday. Participants were instructed to consume the breakfast between 6 am and 10 am (with some flexibility at weekends) and before drinking any tea or coffee or other beverage. They were informed that they would be sent automated text reminders each day about this requirement including a reminder about completing their diary. Instructions about diary completion: Instructions were provided about diary completion emphasizing that they should be completed immediately after finishing breakfast. Participants were also instructed to complete the diary ratings immediately after their main evening meal (of their choice) designated as between 4 pm and 8 pm. Participants were reminded that they were required to send a text message to a pre-assigned SMS service number upon completion of each breakfast and evening meal diary page on each day (used to check compliance with instructions). Participants were escorted separately from the research site by PL or SB to ensure they did not discuss the details of their breakfast allocation with others. When participants returned one week later they completed the FFQ once more using their diary record to help recall what they had eaten in the past seven days (using breakfast and evening meal diary entries and free recall about lunch, snacks and drinks). They were weighed once more. A brief explanation about the purpose of the study was provided that did not reveal the nature of the design and participants were told that a full explanation would be provided at a later date. Data quality and statistical analysis Prior to hypothesis testing the diary records were checked for completeness and cross-checked with SMS messages received from participants. Participants should have sent a total of seven SMS messages; one for each time they completed their breakfast diary page. Of the participants who completed (n = 123), 90% sent five or more SMS messages; 83% between 6 am and 11 am. Participants who did not meet these conditions had either forgotten to text on some days or had technical problems with their phones. Cross-checking with diary entries indicated that the small percentage of participants who had not complied with SMS messaging requirements had recorded dates and times in their diaries that were between 6 am and 11 am. Diary entries for evening meal ratings were checked using the same criteria as breakfast and were found to be as satisfactorily accurate by time

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and date. To have complied with the study the texts should have been sent between 4 pm and 10 pm. Of the 123 participants who complied with the protocol, 76% sent five or more text messages, and 73% sent five or more text messages between 4 pm and midnight. An average of VAS ratings over seven days was calculated from diary ratings separately for breakfast and evening meals to produce summary scores of participant’s rating of perceived calories of meals, hunger, fullness, mood, body and weight satisfaction. The values derived indicate the mean level of each variable across the seven-day assessment period. Statistical analyses were performed using SPSS for WINDOWS software (version 15.0; SPSS Inc., Chicago, IL). The SPSS validation tool was used to check data entry accuracy. All outcome measures were normally distributed and the equality of variance assumption was met. Data is presented as means and standard error of means. Differences between breakfast conditions in baseline characteristics were compared using independent t-tests. Diary VAS ratings were analysed using repeated measures analysis of variance (ANOVA) with time as the within-subjects factor (breakfast meal vs. evening meal) and condition (cereal vs. muffin breakfast) as the between-subjects factor. The ANOVA sphericity assumption was met and the related alpha values are sphericity assumed. Differences between breakfast conditions in terms of estimated energy and nutrient intake were assessed using independent sample t-tests. Results Participant characteristics The psychological and physical characteristics of participants at baseline are depicted in Table 2. There were no significant differences between participants assigned to either breakfast condition (see note to Table 2). The mean values for the TEFQ-R21 scales indicate that the participants did not have high levels of uncontrolled eating, cognitive restraint or emotional eating (scale median = 50). The samples did not report mental health problems as scores on the HADS are in a healthy range (scores are <8 which is a cut-off for possible symptom presence in community samples (Zigmond & Snaith, 1983)). At baseline participants in both conditions had high levels of self-esteem (median for scale = 28) and relatively low levels of shape and weight concerns (median for scale = 48). There was no change in body weight from baseline to completion for either breakfast group (all p > .05; data not shown).

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Effect of breakfasts on mood, body image and appetite The outcome of analysis of variance of diary VAS ratings indicated that significant main effects were qualified by Time-byCondition interactions (Table 3). The cereal breakfast was rated as lower in calories than the muffin breakfast, whereas participants in both breakfast conditions rated the calories of their evening meal similarly. Participants in the cereal breakfast condition felt less hungry, fuller, happier and more relaxed than those in the muffin breakfast condition after eating their breakfast. Regarding the change in ratings from breakfast to evening meal times it is apparent that in the cereal breakfast condition there is consistency in ratings from morning to evening for all VAS ratings except perceived calories of meals being lower at breakfast. By contrast, in the muffin breakfast condition there is a notable improvement in mood ratings by evening meal time, and changes in appetite ratings are markedly different to those in the cereal breakfast condition. Paired contrasts, within the muffin breakfast condition only, indicated that ratings of hunger, fullness, happy and relaxed differed significantly from breakfast to evening (all p < .001). There were significant correlations (all p < .01) between BSQ16 scores (weight and shape concerns) and body satisfaction VAS ratings following breakfast (r = .57) and evening meals (r = .63), and weight satisfaction VAS ratings following breakfast (r = .60) and evening meals (r = 65). Additionally, there were significant correlations (all p < .01) between BMI and weight satisfaction VAS ratings following breakfast (r = .21) and evening meals (r = .18); cognitive restraint was correlated with weight satisfaction VAS ratings following breakfast (r = .23) and evening meals (r = .25) and with body satisfaction VAS ratings following breakfast (r = .20) and evening meals (r = .24). In light of previous research that shows how trait body image satisfaction predicts daily fluctuations in body image satisfaction (Lattimore & Hutchinson, 2010), and that BMI and cognitive restraint are associated with body image satisfaction following food intake or cue exposure (Fett et al., 2009; Geschwind et al., 2008; Vocks et al., 2007), the BSQ-16 scores, BMI and cognitive restraint scores were entered together as covariates in analyses of VAS ratings of body and weight satisfaction. This approach is justified because the covariates were measured before the outcome measure, the covariates have a linear relationship with the outcome measure and groups did not differ on the covariates at baseline (Miller & Chapman, 2001). The outcome of analysis of covariance (see note to Table 1) indicated that ratings of body and weight satisfaction

Table 3 Breakfast and evening meal Visual Analogue Scale (VAS) ratings by breakfast condition. VAS (0–100 mm)

Breakfast condition Cereal (n = 59) Breakfast meal

Perceived calories Body satisfactionb Weight satisfactionc Hunger Fullness Happy Relaxed

Muffin (n = 64)

Evening meal

Breakfast meal

ANOVA (df: 1,121)

Evening meal

Time

Condition

T  Ca

M

SEM

M

SEM

M

SEM

M

SEM

F

F

F

25.7 64.4 64.1 15.1 78.2 73.5 71.3

2.0 2.4 2.5 1.8 2.4 1.9 2.0

57.7 61.4 60.9 13.1 82.8 75.6 75.9

1.7 2.7 2.9 1.4 1.6 1.7 1.8

70.9 50.7 50.1 28.1 65.6 58.1 61.0

1.7 2.8 2.9 2.4 2.5 2.5 2.3

59.3 53.9 52.1 15.6 81.1 70.0 72.3

1.5 2.7 2.8 1.5 1.5 2.0 2.0

41.4*** 0.5 0.5 26.4*** 42.2** 41.2*** 50.9***

149.4*** 7.0** 8.1** 12.6** 8.8* 15.6*** 6.7**

188.4*** 16.0*** 13.4*** 13.8*** 12.3*** 20.1*** 8.5**

Notes: a T  C: Time-by-Condition interaction. b BSQ-16 was used as covariate (df: 1,116) and provided significant adjustment to MSerror (F = 56.7, p < .001) but BMI and cognitive restraint did not (ps > .75). c BSQ-16 was used as covariate (df: 1,116) and provided significant adjustment to MSerror (F = 61.6, p < .001) but BMI and CR did not provide significant adjustment (ps > .61). * p < .05. ** p < .01. *** p < .001.

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Table 4 Estimated energy and nutrient intake for accurate reporters at follow-up and related contribution of major food groups to energy. Breakfast condition Cereal (n = 23)

Energy (kcal) Protein (g) Carbohydrate (g) Total fat (g) Fibre (g) Ca (mg) Fe (mg) Vit. C (mg) Breads (%kcal) Breakfast cereals (%kcal) Biscuit/cake/pudding (%kcal)

t(46) Muffin (n = 25)

M

SEM

%a

M

SEM

%a

1958.2 80.6 245.7 67.6 14.3 1205.6 13.8 145.4 12.5 6.1 4.9

67.4 2.7 7.9 3.2 0.8 53.2 0.4 6.3 1.7 0.2 1.0

– 16 47 31 – – – – –

1830.7 76.5 220.6 71.0 10.9 860.5 8.1 124.0 6.9 0.9 17.3

49.5 3.8 5.5 3.4 0.7 27.3 0.4 6.3 0.9 0.4 0.6

– 17 45 35 – – – – –

1.5 0.8 2.6* 0.7 3.0** 5.9*** 10.4*** 2.3* 2.9** 10.4*** 11.1***

Notes: a Percentage contribution to total energy. * p < .05. ** p < .01. *** p < .001.

varied between conditions such that those in the cereal breakfast condition felt more satisfied about their weight and shape after eating breakfast than those in the muffin breakfast condition. BSQ16 scores provided significant adjustment to the MSerror term but BMI and cognitive restraint did not (the same outcome was observed if the covariates were not entered but F values were marginally different; data not shown).

more Ca, Fe and Vitamin C from their diet over the seven-day period of the trial. The percentage contribution of different food groups to total energy intake was assessed and indicated in the cereal breakfast condition there was a greater contribution to total energy from Breads and Breakfast Cereals and in the muffin breakfast condition there was a greater contribution to total energy from Biscuits/Cakes/Puddings. These differences are generally compatible with the experimental design.

Energy and nutrient intake Discussion The energy and nutrient intake values collected using the FFQ are very low by comparison with the estimated average requirement for energy for women aged 19–50 years (Department of Health, 1991) (approximately 20% below). Inspection of the distributions of daily energy intake values indicated that the absolute mean values are lower than one would expect for women in this age group (baseline vs. follow-up: 1635 kcal vs. 1575 kcal daily). This suggests that participants may be under-reporting daily intake which is a common problem with FFQs (Tooze et al., 2004). The apparent under-reporting of daily energy intake was assessed further by examining the ratio of basal metabolic rate (BMR) to energy intake (Goldberg et al., 1991) using the Schofield equations (Schofield, Schofield, & James, 1985). These ratios clearly indicate that estimated energy intakes were incompatible with maintenance of body weight. At baseline 62 (50%) participants had a kcal/BMR ratio <1.2 and at follow-up 75 (61%) participants had a kcal/BMR ratio <1.2. Mean energy intakes were only marginally higher than estimated mean BMRs which strongly suggest that under-reporting occurred (data not shown). Furthermore it would seem that this is due to under-reporting as such, not a genuine reduction in energy intake throughout the study, since mean body weight did not change in either group (data not shown). The total number of participants who had a kcal/BMR ratio equal to or greater than 1.2 at both time points was too small to justify analysis of changes in nutrient intake over time. However, the sample size of those who appeared to be accurately reporting at follow-up (n = 48) (i.e., that had kcal/BMR ratios  1.2) was sufficient to permit analysis of estimated energy and nutrient intake over the seven-day period of the trial. The means and SEMs for energy, macronutrient intake and selected micronutrients are displayed in Table 4 and represent estimates of intake over the seven days of the trial derived from the FFQ completed at follow-up. The significant differences observed for apparently accurate reporters of nutrient intake indicate that those in the cereal breakfast condition consumed more carbohydrate and fibre than those in the muffin breakfast condition, and appeared to derive

In line with predictions, women who regularly consumed a cereal breakfast believed it to be lower in calories than those who consumed a muffin breakfast, even though both breakfasts were almost identical in energy content. Furthermore, the cereal breakfast appeared to make women feel more satisfied about their body and weight after controlling for pre-existing shape and weight concerns, BMI and cognitive restraint. Additionally, women who ate the cereal breakfast felt fuller, less hungry, more relaxed and happier compared to women who ate the muffin breakfast. These outcomes partly support and extend evidence from previous studies which show that beliefs held about the calorific value of food partly determine psychological reactions to eating, especially body image satisfaction (Fett et al., 2009; Geschwind et al., 2008; Lattimore & Hutchinson, 2010; Vocks et al., 2007). Our study indicates that like previous studies women feel worse about their body image following intake of what they believe is a high-calorie food. By contrast, women feel better about their body image when they believe they are consuming a low-calorie food. The current findings differ from previous studies by indicating that cognitive restraint and BMI do not influence the outcomes observed for body image satisfaction. Previously, Fett et al. (2009) showed that only lean restrained eaters showed reduced weight satisfaction following exposure to high-calorie food cues. Geschwind et al. (2008) indicated that cognitive restraint predicted a decrease in weight satisfaction following exposure to high-calorie food cues. Lattimore and Hutchinson (2010) indicated that in freeliving eating conditions BMI and dietary restraint predicted fluctuations in state body image satisfaction in women attempting weight loss. Although our study does not provide support for the potential influence of BMI and cognitive restraint on body image satisfaction we cannot rule out that these factors would influence outcomes. Both factors did not provide significant adjustment when used as covariates; non-significant effects do not imply that these factors are not relevant. The evidence regarding the potential role of BMI and cognitive restraint is limited to a small number of

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studies and the outcomes vary between studies. In some instances these outcomes may be specific to women attempting weight loss (Lattimore & Hutchinson, 2010), an issue that we did not address in the current study. Further investigations are warranted to resolve these differences using randomised designs where allocation to breakfast meals is made from intact groups defined by BMI and cognitive restraint. The novel aspect of the current study which builds upon previous evidence relates to assessment of psychological reactions, in free-living conditions, to consuming isocaloric meals that were predicted to be perceived as markedly different in calorie content. The use of a cereal-based breakfast provided an ecologically valid and effective contrast to ‘‘forbidden’’ foods typically used in laboratory investigations. By accounting for pre-existing weight and shape concerns it is evident that body and weight satisfaction remain relatively stable from breakfast to evening meal occasions. Participants in the muffin breakfast condition felt fuller and less hungry, and happier and more relaxed after their evening meal compared to their breakfast meal. These differences between breakfast and evening meal ratings warrant further investigation as the study did not attempt to control what was consumed in the evening nor reliably assess energy content of what was eaten. We recommend caution in the interpretation of our findings because the use of an experience sampling methodology is inherently different to the use of controlled laboratory procedures. We could have required participants to attend the laboratory daily to consume their breakfast which would have provided greater control over the eating we aimed to observe. However, such an approach would be categorically different to sampling experience in free-living conditions. The advantage of using an experience sampling methodology rather than laboratory-based methods lies in its ecological validity. The validity of data collected using an experience sampling methodology relies heavily on accuracy of reporting. We took considerable care to remind participants every day using SMS reminders to their cell phones to complete diary ratings. The SMS information we received back from them about time and date of diary ratings they completed suggested that there was very good compliance with the protocol. However, we cannot rule out that some retrospective reporting may have occurred. Although we have proposed that the effects of consuming breakfast on mood, appetite and body image satisfaction are related to beliefs people hold about the effects of the apparent calorific value of the food, it is also evident that breakfasts differing in macronutrient composition have differential effects on appetite and mood (Lloyd et al., 1996; Smith, 2005). Both breakfasts were almost identical in energy content yet were markedly different in composition of protein (cereal: 13.5 g vs. muffin: 4 g), fat (cereal 7.4 g vs. muffin: 14.5 g) and fibre (cereal: 3.2 g vs. muffin: 1.6 g), but similar in carbohydrate (cereal: 66.3 g vs. muffin: 61.4 g). The breakfasts also differed in volume due to the 150 ml of milk consumed with breakfast cereal. The differences observed between breakfast conditions in ratings of hunger, and fullness could be explained by beliefs or expectations held about the effects of the calorific value of the food and physiological effects of the macronutrient composition and volume of the food. However, there is a limit to any conclusions that can be drawn from this study regarding the potential satiating effect of macronutrient composition of breakfasts because fullness and hunger were only self-reported immediately after breakfast rather than throughout the morning and meals were not equal in volume. We cannot rule out the possibility that the effects of macronutrients and volume may explain the differences observed. Rigorously controlled studies indicate that breakfast incorporating significant amounts of proteins and lipids modulates ghrelin secretion and appetite (Foster-Schubert et al., 2008). Dietary fat is less satiating than other macronutrients (Clegg & Shafat, 2010) and studies show that fibre

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(from cereal grains) promotes satiety (Freeland, Anderson, & Wolever, 2009) although the proportions in both breakfasts in the current study are less than amounts previously reported to have an effect (Smith, 2005). Further studies are required to disentangle the effects of psychological reactions from physiological responses to breakfast consumption and to determine how prolonged a satiety response is. Regarding the differences observed between breakfasts for mood ratings it is also difficult to draw firm conclusions about possible macronutrient effects on mood. The muffin breakfast contained chocolate and research has indicated acute effects of chocolate on mood (Macht & Mueller, 2007; Parker, Parker, & Brotchie, 2006). However, cereal intake can also acutely affect mood (Smith & Wilds, 2009). In the current study the cereal breakfast resulted in significantly higher ratings of mood compared to the chocolate-chip muffin. The muffin comprised of 12 g of plain chocolate (17% of total) which is too small to have potential psychoactive effects (Smit & Rogers, 2001). We expect that the difference between breakfasts in mood ratings may be due to expectations of the perceived calorie content of the breakfasts and the influence of product labelling. Further studies are required to assess this proposition by, for example, incorporating a preconsumption rating of mood. The assessment of daily nutrient intake using the FFQ was an exploratory procedure employed to estimate average daily energy intake. The low estimates of energy intake suggest substantial under-reporting. As mean body weights did not change it is unlikely that major changes in energy intake occurred, although the composition of the diets could have changed. Analysis of those who appeared to be accurately reporting, by virtue of acceptable kcal/BMR ratios, indicates that the nutritional differences observed were compatible with the experimental design: greater fibre, calcium and iron intakes for those consuming breakfast cereal (with milk) compared to those consuming the muffin. The rise in iron intake is likely to be associated with consuming the fortified cereal. Furthermore, the differences in the dietary sources of energy: breads, cereals, cakes, etc., are broadly compatible with the composition of the two breakfasts. However, the greater carbohydrate and vitamin C intake of the cereal breakfast group derived from FFQs is not entirely compatible with the experimental manipulation and warrants further investigation (both breakfasts comprised similar carbohydrate and fruit juice supplied similar vitamin C). These differences may reflect a general adjustment in intake later in the day due to breakfast consumption. Overall, the dietary intake pattern of the breakfast cereal group is more favourable in selected nutrients than that of the muffin breakfast group. Seven days is a very short period of time to assess ‘usual’ dietary intake and there is no evidence that the differences observed were sustained in the longer term. The use of a FFQ methodology rather than a food diary with weighed food records places considerable limitations on what can be concluded. A tradeoff had to be made in this study by use of the FFQ which is less intrusive than the diary method with weighed food records. This trade-off was made because the main purpose of the investigation was to assess daily reactions to consuming breakfast. If we had required substantial monitoring in addition to the use of diaries to record reactions to breakfast we would have overburdened participants and potentially biased the recording of momentary reactions to breakfast consumption. Future studies should consider alternative and more reliable methods of measuring daily nutrient intake to ascertain what effect type of breakfast has on nutrient intake throughout the day. The psychological outcomes of this study have potential to inform public heath interventions for weight loss. Regular consumption of breakfast has a range of health benefits (Light-

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owler & Henry, 2009; O’Sullivan et al., 2008; Smith, 1998, 2005). Our study adds to this literature regarding potential psychological benefits. In the current study we did not expect weight to have changed in the short period of a week but other research indicates that regular breakfast intake can aid weight loss attempts (Lightowler & Henry, 2009). Our findings indicate that regular consumption of a cereal-based breakfast has potential to boost mood, body image satisfaction and potentially enhance satiety. In this respect, weight loss intervention studies indicate that overweight individuals experience improved body image satisfaction following a range of intervention therapies (Dalle Grave et al., 2007). Furthermore, recent evidence suggests that changes in weight and body image reciprocally affect each other during the course of lifestyle intervention (Palmeira et al., 2009). Improvement in body image may act as a motivator for healthy weight management behaviours but the relationship may only hold for individuals with average or above average BMI (Heinberg et al., 2001). Our findings indicate that when certain foods are believed to be low in calories (i.e., the cereal breakfast used in current study) women feel better about their body image after consuming them. Future research should examine whether the psychological benefits of regular consumption of a cereal breakfast may aid adherence to, and success in, weight loss interventions. This relationship may be bi-directional whereby consumption of lowcalorie foods during weight loss attempts may prompt feelings of body image satisfaction which could support prolonged adherence to a weight loss diet. Alternatively, consumption of highcalorie food leads to body dissatisfaction, for example, feelings of ‘‘fatness’’. In turn such feelings may then influence subsequent eating patterns, for example, restriction of calories to restore body image satisfaction (Lattimore & Hutchinson, 2010). This study has shown the importance of beliefs held about the nutritional value of foods (there was a huge difference in perception of calories in the two breakfasts) but the basis for these beliefs is unknown; although presumably, a life time’s exposure to health education and advertising play key roles. Although the breakfasts did not impact on self-reported total energy intake they clearly influenced ratings of mood, body image satisfaction, hunger and fullness. In this respect, it is apparent that beliefs held about the nutritional value of foods were associated with some important indicators of health and well-being. Informing consumers about the nutritional characteristics of foods and their potential psychological benefits could be important to address in health promotion. References Barton, B., Eldridge, A., Thompson, D., Affenito, S., Striegel-Moore, R., Franko, D., et al. (2005). The relationship of breakfast and cereal consumption to nutrient intake and body mass index. The national heart, lung and blood institute growth and health study. Journal of the American Dietetic Association, 105, 1383–1389. Benton, D., Brett, V., & Brain, P. F. (1987). Glucose improves attention and reaction to frustration in children. Biological Psychology, 24, 95–100. Benton, D., Griffiths, R., & Haller, J. (1997). Thiamine supplementation mood and cognitive functioning. Psychopharmacology, 129, 66–71. Benton, D., Haller, J., & Fordy, J. (1995). Vitamin supplementation for 1 year improves mood. Neuropsychobiology, 32, 98–105. Burr, M., Fehily, A., Rogers, S., Whelsby, E., King, S., & Sandham, S. (1989). Diet and reinfarction trial (DART). Design, recruitment and compliance. European Heart Journal, 10, 558–567. Cho, S., Dietrich, M., Brown, C. J. P., Clark, C. A., & Block, G. (2003). The effect of breakfast type on total daily energy intake and body mass index. Results from the Third National Health and Nutrition Examination Survey (NHANES III). Journal of the American College of Nutrition, 22, 296–302. Clegg, M., & Shafat, A. (2010). Energy and macronutrient composition of breakfast affect gastric emptying of lunch and subsequent food intake, satiety and satiation. Appetite, 54, 517–523. Crawley, H. (1994). Food portion sizes. London: HMSO. Dalle Grave, R., Cuzzolaro, M., Calugi, S., Tomasi, F., Temperilli, F., Marchesini, G., et al. (2007). The effect of obesity management on body image in patients seeking treatment at medical centers. Obesity, 15, 2320–2327.

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