to McGill U School of Dietetics & Human Nutrition: 27 Nov 08 Food consumption patterns to reduce and prevent obesity David Booth School of Psychology, College of Life & Environmental Sciences, University of Birmingham (U.K.) http://www.psychology-people.bham.ac.uk/people/david.booth Project with: Louise Thibault, Nutrition, McGill U, Quebec; Caroline Chesneau, INA Paris France; Seolhyang Baek, Nursing, Dongguk U, South Korea; Antonio Laguna-Comacho, Nutrition UAEM, Mexico / Psychology B’ham U, UK .
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to McGill U School of Dietetics & Human Nutrition: 27 Nov 08 Food consumption patterns
to McGill U School of Dietetics & Human Nutrition: 27 Nov 08 Food consumption patterns to reduce and prevent obesity David Booth School of Psychology, College of Life & Environmental Sciences, University of Birmingham (U.K.) http://www.psychology-people.bham.ac.uk/people/david.booth - PowerPoint PPT Presentation
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to McGill U School of Dietetics & Human Nutrition: 27 Nov 08
Food consumption patterns
to reduce and prevent obesity
David BoothSchool of Psychology, College of Life & Environmental Sciences,
University of Birmingham (U.K.)http://www.psychology-people.bham.ac.uk/people/david.booth
Project with:
Louise Thibault, Nutrition, McGill U, Quebec; Caroline Chesneau, INA Paris France; Seolhyang Baek, Nursing, Dongguk U, South Korea; Antonio Laguna-Comacho, Nutrition UAEM, Mexico / Psychology B’ham U, UK.
Slowing the rise of obesityObviously,exercise more and/or eat less!!
Slowing the rise of obesity
Exercise more and/or eat less, as a society (?)
Slowing the rise of obesity
Exercise more and/or eat less, as a society, after big changes (?)
Slowing the rise of obesity
Exercise more and/or eat less, as a society, after big changes (?)
No, obesity is not solely an issue of societal reform, e.g.
public health interventions,
governmental regulations,
responsible businesses.
No doubt, we need all that – but of the right sort.
In the first instance, obesity is not even a societal issue at all.
It’s the individual who is obese or becomes overweight
and has to find ways to exercise more and/or to eat less.
Slowing the rise of obesity
Exercise more and/or eat less:
- each individual within current environment and biology;
- permanently, i.e., maintained across changes in own lifestyle.
Slowing the rise of obesity
Exercise more and/or eat less: - each individual within current environment and biology;
- permanently, i.e., maintained across changes in lifestyle.
Which feasible exercising or eating patterns are
most effective at keeping weight off?
Slowing the rise of obesity
Exercise more and/or eat less: - each individual within current environment and biology;
- permanently, i.e., maintained across changes in lifestyle.
Which feasible exercising or eating patterns are
most effective at keeping weight off?
The societal problem is lack of such research
– and for long past (>= 50 yr).
Slowing the rise of obesity
Exercise more and/or eat less: - each individual within current environment and biology;
- permanently, i.e., maintained across changes in lifestyle.
Which feasible exercising or eating patterns are
most effective at keeping weight off?
After we get some of this evidence,
we can start looking for the further evidence needed
to start reducing obesity in individuals
and preventing overweight even.- then (NEXT TWO SLIDES)
Slowing the rise of obesity
Exercise more and/or eat less: - each individual within current environment and biology;
- permanently, i.e., maintained across changes in lifestyle.
Which feasible exercising or eating patterns are
most effective at keeping weight off?
Educate all in such evidence on the behaviour-patterns to change
[avoid overweight] when unhealthy BMI becomes likely, and
[reduce obesity] when needing to lose some more weight:
- the same energy-balance affecting habits
for prevention and reduction of obesity.
Slowing the rise of obesity
Exercise more and/or eat less: - each individual within current environment and biology;
- permanently, i.e., maintained across changes in lifestyle.
Which feasible exercising or eating patterns are
most effective at keeping weight off?
Educate all in this evidence on the patterns to change
when unhealthy BMI becomes likely, or
when needing to lose more weight.
Environmental reform to prevent lapsing from each change,
“Eat fresh fruit & salad instead ofhigher-calorie foods” 0.21
Score combining the above three 0.28
I.e., cutting out energy intake between meals is the most important “least fattening habit”
Research into effective behaviour (comprehensively across patterns)
(1) A.J. Blair & co (1989) as in Booth et al. (2004)
Most fattening customs of eatingin the English Midlands
1A: energy in or with drinks between meals
Full exploitation of such PSYCHOSOCIAL evidence requires ‘translation’ into the PSYCHOBIOLOGY,
e.g. (in this case – Factor 1A), timings and sizes of the ‘snack’ and the meal before.
Measure the effects of ‘late mixing’ on gastric emptying Calculate long-term consequences for body weight(Booth & Mather 1978; also Booth IJV&N [Swiss Nutrition Society] 1988)
“Snacking” that is fattening:
NOT a snack in the sense of a light meal;
NOT eating a snack-food (if part of a meal).
Energy sources consumed between regular meals, e.g. in or with drinks an hour or more before a mealtime.
Snacking can be addictive -
NOT because of “palatability” of the food snacked on;
NOT because of “pleasure” or “reward” from sweet (or salty) taste or from crunchy or succulent texture;
NOT because of “weakness in satiety”.
Ingestive movements on any ‘nibble’ / ’sip’ available after a meal are associatively conditioned by glucose from (unsweet, fat-free) starch in that food/drink item.
Research into effective behaviour (comprehensively across patterns)
(1) A.J. Blair & co (1989) as in Booth et al. (2004)
Most fattening customs of eatingin the English Midlands
1B: high-fat foods/cooking
Self-described pattern of Correlation with eating and drinking wt. loss in 1 yr
“Avoid unnecessary fat in meals” 0.23
“Avoid fat in cheese and cream” 0.20
“Keep fat down when using spreads” 0.21
Score combining the above three 0.22
Full exploitation of this PSYCHOSOCIAL evidence requires ‘translation’ into the PSYCHOBIOLOGY of the mouthful:
Fat does satiate strongly but late after its ingestion, e.g., through glucose-sparing oxidation of fatty acids in the triglycerides still in chylomicrons long after the meal.
High-fat foods are fattening -
NOT because high “palatability” increases volume eaten;
NOT because of a high-fat “behavioural phenotype”.
Deposition of adipose fat requires energy to synthesise fatty acids from acetate produced from dietary carbohydrate or protein, unlike deposition from dietary fat.
Eating of high-fat foods is learnt by custom:
NO texture, aroma or taste of “fat” across all high-fat foods;
NO innate preference for fat-based creaminess or crunchiness.
NOT “weakly satiating”: like protein, delayed metabolic satiation.
Traditional or prestigious foods are often high in fat, e.g. (in UK) foods that store well (because of low water activity), foods for masculine image of men (‘great British breakfast’; ‘red’ meat).
Research into effective behaviour (comprehensively across patterns)
(1) A.J. Blair & co (1989) as in Booth et al. (2004)
Most fattening customs of eatingin the English Midlands
Dieting OR Extreme exercise
Correlation of 1-yr weight loss &
Self-described habit frequency of habit
Predicted to be counterproductive (unsustainable, hence de-motivating -> yo-yo)
“Eat slimmers’ meal replacements for one or more meals a day” - 0.05
Predicted to spend extra energy but not to be maintained; hence yo-yo dieting
“Do vigorous exercise regularly” - 0.09
Predicted to spend extra energy and to be a maintainable routine
“Walk or cycle whenever possible” 0.04
Might help identify (=expertise) and/or sustain (=motivation) weight-losing habits
“Go to a slimming club or weight reduction class” 0.11
Research into effective behaviour (comprehensive of the patterns)
(1) A.J. Blair et alii (1989) Psyc Health; D.A. Booth et alii (2004) Appetite
Strengths• Practices asked about edited from words by members of public
- edited into smaller number by using examples from public (AL-C now getting public’s own groupings of new examples)
• Reported weights prospectively at 0 and 12-14 months.• Bivariate analyses from factor-analytical latent variables.• Measured behaviour at the end of the study period. RCTs confound effectiveness of package with adherence to it cp. Knauper et al. ’05 (McGill Psychology) re ‘self-set rules’.
[Blair et al. also assessed beliefs in efficacy of each practice, plus psychological barriers, e.g.:-
chronic dieting (‘restraint’), lack of reasons for action (‘attitudes’)]
Research into effective behaviour (comprehensive of the patterns)
(1) A.J. Blair & co (1989) as in Booth et al. (2004)
Weaknesses• Only one year tracked - need longer for obesity-adequate measure of persistence
• Direct questions about frequency of practices: - unreliable heuristics (e.g., P Slovic; P Sedlmeier & T Betsch, ‘Etc.’) - need timing of two most recent episodes to calculate real frequency (over the exact period since the earlier occasion).
• Analysis only of final frequency - need change in frequency to measure cause of weight change
• Only two points and so no crossed time-lags possible - needed to measure effect of behavour on weight as distinct from
wt on bhvr, or both from 3rd factor causing both changes
Research into effective behaviour (comprehensive of the patterns)
• Large number (23) of so-called “specific weight control behaviors”
• Four successive years of data from N = 1120 (Pounds of Prev’n study)
• The year’s duration of use of each practice recalled
[Prevalences reported (yet again): these may screen for feasibility]
Weaknesses
• Behavioural patterns not specific in analysis, nor defined in report
• Wordings “developed by researchers”: ??recognition by participants
• Orthogonal latent factors not extracted
• Current behaviour not measured at time of weight measurement; hence an association over the year (or 4y) is fallacious because weight stays at asymptote only while behaviour persists.
Raynor, Jeffery et al. (2008) did not replicate in N = 5145 over 1 year in t2D for cutting out sweets, increasing F&V, eating less hi-CHO food.
Research into effective behaviour (comprehensive of the patterns)
should be treated as supplementary outcomes and/or motivational moderators (Blair et al., 1989; Lewis, Blair, Booth, 1992a,b)
Important ‘selective’ studies
Coakley et al. & Willett (1998) IJO 22, 89-96: 4y prosp’ve; N=19.5k snacking fattens, not fat intake (except oldest); TV & no vigorous PA
Knauper et al. (2005) Appetite on self-set rules in wt. control: persistence (compliance) usually confounds effectiveness
Disconfounding is possible only if change in each behaviour is tracked during weight loss;
not done by the best RCT so far (DPPRG, 2002 NEJM): weight still increasing at 2y, while PA relapsing; no ‘dietary’ data
Research into effective behaviourcomprehensive across specific self-described patterns
Follow-up & extend Blair et al. (1989) as in Booth et al. (2004, 2007)
Research trainee’s pilot at McGill with updated methods - particularly weekly tracking and cross-lagged analyses (Baek)- ’localised’ (shift culture) to Montreal, French language & students
Concluding part of this talk using Symposium (2006) slides on http://epapers.bham.ac.uk
Research student’s project at Brum- nutrition graduate / obesity dietitian for a degree in psychology
First year: strengthen different parts of the methods e.g. update elicitation & categorisation of descriptions validate recall of self-described activities
Second year onwards: weekly reporting weight & timings of bhvr multiple-baseline to asymptotic weight persistence & antecedents of lapses
More in future at McGill??
Yet more applications for research grants in UK
Theory of ‘enABLE’ research method
1. A subculture’s consensus descriptions of customs objectify communicable patterns of activity.
Theory
1. A subculture’s consensus descriptions of customs objectify communicable patterns of activity.
2. Autobiographical memory can time episodes of an activity as accurately as a diary record can.
Theory
1. A subculture’s consensus descriptions of customs objectify communicable patterns of activity.
2. Autobiographical memory can time episodes of an activity as accurately as a diary record can.
3. A sustained change in frequency of a custom of eating or moving about will change body weight towards asymptote over a few weeks.
Theory
1. A subculture’s consensus descriptions of customs objectify communicable patterns of activity.
2. Autobiographical memory can time episodes of an activity as accurately as a diary record can.
3. A sustained change in frequency of a custom of eating or moving about will change body weight towards asymptote over a few weeks.
4. Change to a frequency that is sufficiently prevalent in a culture will be maintained indefinitely, along with the asymptotic change in body fat content.
Theory
1. A subculture’s consensus descriptions of customs objectify communicable patterns of activity.
2. Autobiographical memory can time episodes of an activity as accurately as a diary record can.
3. A sustained change in frequency of a custom of eating or moving about will change body weight towards asymptote over a few weeks.
4. Change to a frequency that is sufficiently prevalent in a culture will be maintained indefinitely, along with the asymptotic change in body fat content.
5. Antecedents to lapse from change can be identified in food supply, transport and built environment, and evidence found for effective changes in them.
Varieties of intervention
Measurement (tracking) only: “observational”
Multiple-baseline with tracking: quasi-experimental
Multiple baseline tracking in RCT: experimentalversus other wordings of behaviour-changes
The McGill pilot study (observational) Method (with some short-cuts)
1. Consensus descriptions elicited in one culture (UK) were ‘localised’ to another culture (Quebec French) by investigators as participant observers, checked by back-translation to England’s language and environs.
2. Exact current frequency is given by the reciprocal of the time difference between the last two occasions.
3. Effect on weight of maintained change in frequency of a custom after the first week (or 2 weeks) was measured by correlation between the changes,
4. Effects of initial and changed custom frequencies on behaviour change maintenance (and weight change maintenance for an effective custom) were expressed as ‘dose-response’ slopes.
Design
Convenience sample of French-speakers in Montreal:21 recruited; 14 completed the planned 6 weeks of the study: 12 women and 2 men, ages 18-46 years.
At the same time of day on the same day of the week, on a questionnaire in French, each reported body weight (weighed that day on the same scales) and recalled the last two timings of carrying out each of 26 customs of eating and/or drinking and 6 customs of moving about.
AnalysisCorrelations of changes in behaviour and weight (1)
Results are expressed here as r x 100, where r is Pearson’s product-moment correlation coefficient.[Where data are seriously skewed, Spearman’s correlation of ranks, rho, should be used instead.]
If only one pattern of energy intake or expenditure changes in frequency in a given week, correlation with weight change can in theory be perfect (r = 1.0).
With such a small sample, the observed r values are highly unreliable. [When N is adequate for good estimates of effect size, the 95% confidence limits of r should be given.]
Correlations of changes in behaviour and weight (2)
Positive values indicate that the activity is fattening.Negative values indicate an effective slimming habit.
Test of the causal hypothesis:Frequency change correlates with later Weight change. This is a rather severe test, discounting weight lost in 1st week or two (though 1st week is mainly water).
Cross-lagged control:Weight change does not correlate in the same direction with later Frequency change. Correct the r-value measuring Frequency on Weight by subtracting r-value for Weight on Frequency.
Effect of belief on behaviour:Weight change correlated in the opposite direction with later Frequency change indicates action on a correct belief as to what can produce that change in weight.
Evidence for eating that slims in Francophone Canada
correlation of amount of one change in first week of that changewith amount of the other change in subsequent two weeks
r x 100 r x 100 rF,W - rW,F rW,F/rF,W
Activity (described Freq 0-1 Wt 0-1 Cross-lag Strengthin French = “…”) Wt 1-3 Freq 1-3 corrected of belief
smaller meal a -63 -50 -13 -
vegetables in meal -85 54 (-85) 0.6
cheese, dairy cream b -93 38 (-93) 0.4
food with added sugar -25 58 (-25) 2.3
“sucreries en ‘surplus’” -30 45 (-30) 1.5
a smaller than ‘normal’. b “des matières grasses animales [sic] sous forme de ...”
Customs that slim in Montreal (described in French)
Means of correlation values (r x 100) available from up to four lags: behaviour-Frequency change over one week (F0-1) or two weeks (F0-2) and Weight change over the next week (W1-2,W2-3) or two (W1-3,W2-4).
Mean Mean Mean Mean Pattern of behaviour Freq Wt on cross-lag strength
on Wt Freq corrected of belief
smaller meal -62 -43 [-60] 0.9
vegetables in meal -28 -9 -14 [3.0]
cheese, dairy cream -70 17 -48 0.2
food with added sugar -6 45 [-6] 4.3
“sucreries en ‘surplus’” -10 16 1 -
take exercise until tired -34 -28 [-15] 2.4
[…] = (mean) difference from two of the four (or one of the three) lags available
Customs that fatten in Montreal (described in French)Frequency change over one week (F0-1) or two weeks (F0-2) and Weight change over the next week (W1-2,W2-3) or two (W1-3,W2-4) - mean values
Mean Mean Mean Mean Pattern of behaviour Freq Wt on cross-lag strength
on Wt Freq corrected of belief
use fat in cooking/prep’n 59 20 57 -
drink alcohol 53 -48 (40) 1.1
choose fibre-rich foods 55 11 31 -
eat fruit or salad 73 7 65 -
aerobics/“un club sportiv” 75 18 62 -
Other ways to test the causal hypothesise.g., correlation (unlagged) of a persisting change in frequency of an activity with the amount of weight lost
Less food than normal in a meal
0.00 1.00 2.00 3.00 4.00 5.00
weight change
-40.00
-30.00
-20.00
-10.00
0.00
10.00
Big
ge
st c
ha
ng
e i
n F
re
qu
en
cy
1
2
6
7
12
13
14R Sq Linear = 0.396
Increase in frequency with greatest decrease in weight
Decrease in frequency (briefly) with (almost) no change in body weight
Each person’s biggest change in frequency during a period of consistentlyup or down change
Change in weight (kg t1 – t2)) over whole period of change
Does maintenance of changed frequency of a practice depend on how frequent the custom was or is?
Less food than normal in a meal
0.00 3.00 6.00 9.00 12.00 15.00
F0
2.00
2.50
3.00
3.50
4.00
4.50
5.00
No
.of w
ee
k
1
2
6
7
12
13
R Sq Linear = 0.311
-6.00 -4.00 -2.00 0.00 2.00 4.00 6.00 8.00
F0-1
2.00
2.50
3.00
3.50
4.00
4.50
5.00
No
.of
week
1
2
6
7
12
13
R Sq Linear = 0.386
Number
of
weeks
Number
of
weeks
Starting frequency (times per week) Frequency change in first week of change
No sign of effect of size of increase* in frequency.
(Sharp decreases were not well sustained.)
Change in frequency [increase*] of eating smaller meals is maintained for longer if frequency starts higher.
down up
The bigger picture for research (1)
The psychobiological “long haul” (Booth, 1988) = study of the mechanisms of appetite and its sating,
and of vigour and its fatigue . physically energetic
- by itself, such work can’t show how to control weight;
- yet the mechanisms of choice and its satiety/fatigue must be measured, in order to work out how to support these psychosocially identified maintainable least fattening customs,
e.g. through supply of foods, transport, leisure, etc.
The bigger picture for research (2)
Psychosocial “short-cut” (B ’88)
Generalise and differentiate frompersonally tailored locally valid evidence
Track changes in behaviour components - causal evidence without experiment - the only way to rescue obesity RCTs
from unusability and invalidity.
The future for enABLEr/s
Provide service through the researchGenerate research through services
Begin to educate the public (& professionals) inpersonally tailored locally valid evidence to inform a succession of changes each 1-3 weeks,
- especially of eating habits when a more sedentary lifestyle begins.
Create demand on commercial and public providersTo change supply in ways that evidence shows to support effective maintainable patterns of individual behaviour.
Thank you for your attention
SPARE SLIDES
Bio
‘Bio’
David Booth has research doctorates in biochemistry and in psychology.
One of his main areas of research since 1964 has been the neural, digestive, metabolic, sensory and social influences on, and effects of, choices and intakes of foods and drinks, and how all these causal processes interact in the individual’s life.
One major effort has been to characterise and to measure the least fattening customs of eating within local environments. This talk will highlight a pilot study conducted in this School that is now being extended by a nutrition graduate and obesity dietitian from Mexico who is studying for a research degree in Psychology with David and colleagues at the University of Birmingham.