Mood, Emotions and Food Choice

Abstract

Comfort eating, that is eating induced by negative affect, has been a core theme of explanations for overeating and obesity. Psychobiological explanations and processes underlying comfort eating are examined, as well as its prevalence in clinical and nonclinical populations, to consider who may be susceptible, whether certain foods are comforting, and what the implications for treatment may be. Comfort eating may occur in a substantial minority, particularly in women and the obese. Human and animal theories and models of emotional or stress-induced eating show some convergence, and may incorporate genetic predispositions such as impulsivity and reward sensitivity, associated with dopamine dysregulation underlying incentive salience. Comfort eaters show vulnerability to depression, emotional dysregulation and a need to escape negative affect and rumination. During negative affect, they preferentially consume sweet, fatty, energy-dense food, which may confer protection against stress, evidenced by suppression of the hypothalamic–pituitary–adrenal axis response, although activation of the hypothalamic– pituitary–adrenal axis may itself drive appetite for these palatable foods, and the risk of weight gain is increased. Benefits to mood may be transient, but perhaps sufficient to encourage repeated attempts to prolong mood improvement or distract from negative rumination. Cognitive behavioural treatments may be useful, but reliable drug therapy awaits further pharmacogenomic developments.

Full text

PCOS 2009
Dr Leigh Gibson
Roehampton University
1
Dietary Management in Polycystic Ovary
Syndrome April 2009
Mood, Emotions and Food Choice
Dr Leigh Gibson
Reader in Biopsychology
Clinical and Health Psychology
Research Centre
School of Human and Life Sciences
Whitelands College
Roehampton University
London
http://www.roehampton.ac.uk/researchcentres/chp/index.html

PCOS 2009
Dr Leigh Gibson
Roehampton University
2
Why look at mood and food choice?
“Let me have men about me that are fat;
Sleek-headed men, and such as sleep o' nights:
Yond Cassius has a lean and hungry look;
He thinks too much: such men are dangerous.”
Caesar in W. Shakespeare’s “Julius Caesar”, Act 1, Scene (ii).
.30 .39
Vitaliano et al. (2002)
(prospective data from male AD carers)
Poor diet
Low activity
Psych
Distress
Chronic
Stress CHD
.50 .33 Metabolic
Syndrome

PCOS 2009
Dr Leigh Gibson
Roehampton University
3
Child Eating Behaviour Q scales predict adiposity over a
wide range in 10,359 8-11-y-olds
(Carnell & Wardle, 2008)
‘Satiety resp. + Slow eating’ ‘Enjoyment of Food’

PCOS 2009
Dr Leigh Gibson
Roehampton University
4
Food choice and current internal state
• Anticipation of shifting
internal state* from
current (need) to
required (ideal/sated)
state
• Adaptive eating, or
successful
‘homeostasis’, depends
on accurate learning
and reliable stimuli
• Maladaptive eating –
‘wrong’ choices can be
rewarding too…
*nutritional, cognitive, emotional

PCOS 2009
Dr Leigh Gibson
Roehampton University
5
Tasting water

PCOS 2009
Dr Leigh Gibson
Roehampton University
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Tasting sucrose solution

PCOS 2009
Dr Leigh Gibson
Roehampton University
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Tasting lemon juice

PCOS 2009
Dr Leigh Gibson
Roehampton University
8
Opioids mediate both hedonic and
motivational aspects of appetite
Berridge (2009)
Tongue protrusion
gape

PCOS 2009
Dr Leigh Gibson
Roehampton University
9
Eating: pleasure from sensation and
energy.…satisfying hunger
+
• Sweet and fatty energy-rich
foods are highly rewarding…
• …and make us feel
better…
• …so that we really want
(crave) them during hunger
or stress.
• Problem:
- energy dense foods
encourage overeating, thus
obesity.
-
Only some people are
susceptible.

PCOS 2009
Dr Leigh Gibson
Roehampton University
10
• Why is chocolate craved and habit-forming?
• Is the craving just a strong appetite created by eating
chocolate when hungry?
• Can it be extinguished by eating chocolate only when full?
Craving for Chocolate

PCOS 2009
Dr Leigh Gibson
Roehampton University
11
Chocolate ‘craving’ depends on eating it when hungry:
eating chocolate when full extinguishes craving
Pre Post Pre Post Pre Post Pre Post
0
20
40
60
80
100
Craving for Chocolate
CRAVERS
a
bc
A
Hungry Full
Training State:
Hungry Full
Test State:
Hungry Full
(2 weeks)
Gibson &
Desmond
(1999)

PCOS 2009
Dr Leigh Gibson
Roehampton University
12
Food cravings decrease on a Very Low Calorie Diet*
– and remain low on refeeding
(Martin, C.K. et al., 2006, Obesity, 14, 115-121)
*800-1000
kcal/day
- mainly liquid
supplement

PCOS 2009
Dr Leigh Gibson
Roehampton University
13
Does chocolate cause a ‘sugar rush’ leading
to mood fluctuation?
From Chocolate Week 2004 (UK) website
The measure for the change in blood glucose
after eating a fixed load of carbohydrate is
known as the ‘Glycaemic Index’...
“…shortly after eating it, you feel great, consumed by a surge of
energy, followed by a low when the sugar rush runs out…”

PCOS 2009
Dr Leigh Gibson
Roehampton University
14
Glycaemic Index
(vs. White Bread = 100)
Data from Foster-Powell, Holt & Brand-Miller (2002)
56
57
61
72
77
87
88
89
94.5
97
97
100
112
113.5
158
0 50 100 150 200
apple
baked beans
chocolate, milk
spaghetti
Alpen muesli
white rice
sucrose
Mars bar
banana
carrot/parsnip
Fanta drink
white bread
cornflakes
potato, boiled
potato, baked
Chocolate is a low GI food! Don’t expect a
“sugar rush”
[Healthy subjects]

PCOS 2009
Dr Leigh Gibson
Roehampton University
15
Blood glucose levels in women self-
reporting hypoglycaemic symptoms vs.
matched controls:
• Symptomatic levels are lower than asymptomatic or control levels,
and occur before 3 hr after eating
Simpson et al. (2006) BJN
14% <= 3 mmol/L
2% <= 3 mmol/L
2% <= 3 mmol/L

PCOS 2009
Dr Leigh Gibson
Roehampton University
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Under-eating on active days may cause “hypoglycaemic”
symptoms in healthy women
E Req E Eaten E Req E Eaten E Req E Eaten
5
6
7
8
9
10
Energy Required and Energy Eaten (MJ)
.
Adapted from Simpson et al. (2006) BJN, 95, 1127-1133
Control Group
RH - No Symptoms
RH - Symptoms
**
Simpson et al. (2006)
Fat & Protein intake (g):
RH-S < Controls
RH-S more active than RH-NS

PCOS 2009
Dr Leigh Gibson
Roehampton University
17
Self-reported “Hypoglycaemics” may be more
sensitive to falling blood glucose
Thus, during falling blood glucose:
• Higher glycaemic thresholds for counter-regulatory hormone release
and impairment of reaction time
• Greater beta-adrenergic sensitivity
• Possible explanation: failure to match increased energy expenditure
with increased intake (on active days) (Simpson et al., 2006)
• Perhaps also, reduced fat and protein intake (relatively high-CHO
diet – greater insulin response?) – underreporting of sugary drinks?
(Snorgaard et al., 1991; Berlin et al.,1994)

PCOS 2009
Dr Leigh Gibson
Roehampton University
18
Mechanisms for stress/negative affect-
induced changes in eating and food choice
•Stress-coping strategies (e.g.
eat to distract, emotional or
‘comfort’ eating – eating to
improve mood/reduce stress).
• Motivational differences (e.g.
reduced concern about weight
control; helplessness, depression
and loss of appetite).
• Physiological - reduced appetite
caused by physiological arousal,
or cachexia.
• Practical - changes in eating
opportunities, food availability,
meal preparation, convenience.

PCOS 2009
Dr Leigh Gibson
Roehampton University
19
Perceived stress-induced changes in food choice in 212
students reporting eat less, the same or more overall
Figure from Gibson (2006). Data from Oliver & Wardle (1999)
Eat much more than usual
Eat much less than usual
Eat the same as usual
38% 42%
20%

PCOS 2009
Dr Leigh Gibson
Roehampton University
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In 135 Roehampton students: similar
story for sweets and chocolate
(E. L. Gibson & K. Harris,
unpublished data)
Perceived change in eating under stress
Eat much more than usual
Eat much less than usual
Eat the same as usual
N= 38 34 63

PCOS 2009
Dr Leigh Gibson
Roehampton University
Potential predictors of susceptibility
• Nature of the stress
– severity, emotional or physical distress, work
demands, life events …
• Coping ability, stress-proneness
– psychological and physiological reactivity ...
• Individual differences in eating behaviour
– dieting, restraint, emotional eating, gender,
food preferences, nutritional status ...

PCOS 2009
Dr Leigh Gibson
Roehampton University
22
Eating attitudes: some people are
more at risk than others…
Q1. “When I feel anxious, I find myself eating.”
= ‘Emotional Eating’
Q2. “Sometimes when I start eating, I just can’t seem to
stop.”
= ‘Uncontrolled (Disinhibited) Eating’
Q3. “I consciously hold back at meals in order not to gain
weight.”
= ‘Restrained Eating’

PCOS 2009
Dr Leigh Gibson
Roehampton University
23
Correlation of Eating Attitudes* to
Stress-Eating Tendency:
• Emotional eating: rho(135) = 0.59***
• Uncontrolled eating: rho(135) = 0.33***
• Restrained eating: rho(135) = 0.07 NS
• Perceived currently overweight: rho(135) =
0.23**
(E. L. Gibson & K. Harris, unpublished data)
Emotional eating is best predictor;
Restrained Eating is Not Related
*(TFEQ-R18)

PCOS 2009
Dr Leigh Gibson
Roehampton University
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Kandiah et al. (2006):
• Survey of stress eating habits of 272 female US college students.
• 62% eat more when stressed.
• Stress increases mainly sweet fatty and savoury (fast) foods.
• No effect of restrained eating (single-item Q).
Zellner et al. (2006):
• 169 US male & female UGs surveyed.
• Stress increases sweet fatty foods esp. chocolate.
• More commonly in ‘restrained’ eaters (Herman & Polivy Restraint
scale).
• Foods chosen are those normally avoided as fattening – eaten “to
feel better”.
Other recent surveys

PCOS 2009
Dr Leigh Gibson
Roehampton University
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Effect of Food Liking on Pain Tolerance
(in 40 US female students)
12
14
16
18
20
Tolerance to Finger Pressure
(cm)
Nothing
Neutral - rice cakes
Liked - chocolate cookie
Disliked - black olives
*
Eating a much-liked (chocolate) food increases tolerance of
pain: Mediated by release of opioid neuropeptides?
Data from Mercer & Holder (1997)

PCOS 2009
Dr Leigh Gibson
Roehampton University
26
Smit HJ, Gaffan EA & Rogers PJ (2004)
Caffeine (19 mg) + Theobromine (250 mg) (doses found in
chocolate) and cocoa powder (11.6 g) improve
performance and mood

PCOS 2009
Dr Leigh Gibson
Roehampton University
27
Key points from self-report surveys
• Stress often increases consumption of
(sweet fatty) energy-dense snack foods,
even where the overall tendency is to eat the
same or less.
• Stress affects people differently – eat
less/lose weight vs. eat more/gain weight.
• Emotional/uncontrolled eating, but not
cognitive restraint, best predicts tendency to
overeat during stress.

PCOS 2009
Dr Leigh Gibson
Roehampton University
28
Stress and food choice:
a laboratory study
• Participants: non-smoking, non-obese men (n=27) and women (n=41)
from London University, volunteered to take part in a study of “the
effects of hunger on physiology, performance and mood”.
• Stressed group manipulation: anticipated public speaking - 10-minute
preparatory period before lunch.
• Speech scheduled for after lunch, to provide sustained stress during
eating.
• Control group given non-stressful task - listening to 10-minute
passage of recorded poetry.
• Lunch: ad-lib buffet of assorted cold foods from six categories: low-
and high-fat, salty, sweet and bland foods.

PCOS 2009
Dr Leigh Gibson
Roehampton University
29
Stress increases intake of sweet
fatty foods in emotional eaters*
0
50
100
150
200
250
300
350
Control Stressed
Intake of Sweet Fatty Foods
(kcal)
Low Emotional Eaters High Emotional Eaters
Oliver, Wardle & Gibson (2000)
*DEBQ-E
(not Restraint)
2.44 2.10 2.11 2.55 kcal/g
Stress x Emo. Eating, p<0.05
*
Laboratory study:

PCOS 2009
Dr Leigh Gibson
Roehampton University
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• “SAD” sufferers prefer sweeter foods during the winter
(Kräuchi et al., 1999)
• Obese Swedes with strong liking for sweet/fatty foods
are more anxious (stress vulnerable) (Elfhag &
Erlanson-Albertsson, 2006)
• Stress-reactive female ‘binge eaters’ chose more
sweet/savoury snacks vs. fruit and veg, when
stressed (Goldfield et al., 2008)
Emotions, stress susceptibility and energy-
rich foods

PCOS 2009
Dr Leigh Gibson
Roehampton University
31
Striatal dopamine receptor availability is
inversely related to BMI in obese subjects
Wang et al. (2004)
• No relationship seen for
lean controls.
• Cause and effect not
known.
• Could be a consequence
of high frequency of
palatable food
consumption.
• Binge eaters show
enhanced reward
processing to palatable
food pics (brain fMRI;
Schienle et al., 2009).

PCOS 2009
Dr Leigh Gibson
Roehampton University
32
• Experience of repeated stress,
repeated food restriction, and highly
palatable food (HP; choc cookies) is
necessary to see binge-like overeating in
rats (Hagan et al., 2002).
• Also, chronically stressed rats show
DA output in reward pathway (n. Acc.),
but this is prevented by training to find
sweet vanilla pellets (Nanni et al., 2003),
probably via gluco-corticoid and insulin
action (Dallman et al., 2005).
Stressed rats learn to binge on chocolate cookies

PCOS 2009
Dr Leigh Gibson
Roehampton University
33
Rat ‘stress eating’ is opioid dependent
…blocked by naloxone
(Boggiano et al., 2005)

PCOS 2009
Dr Leigh Gibson
Roehampton University
34
Carbohydrate-Rich/Low-Protein meals can raise brain 5-HT
(serotonin) synthesis by increasing tryptophan (TRP) entry
into brain sedation, calming
TRP
LNAA LNAA
TRP
Insulin
Blood Brain
TRP Hydroxylase
[5-HTP]
5-HT
FFA
Alb
BBB
Dietary “self-medication” via Serotonin?

PCOS 2009
Dr Leigh Gibson
Roehampton University
35
Rat brain TRP 5-HT increased at 2 hours after
0% (pure CHO) and 6% protein meals
No Food CHO 6% Pro 12% Pro 24% Pro 40% Pro
Meal Content
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
TRP:LNAA
Ratio
Hypothal
TRP umol/g
Hypothal
5HTP ug/g/10
Fernstrom & Fernstrom (1995)

PCOS 2009
Dr Leigh Gibson
Roehampton University
36
Stress protective effect of CHO-rich/PRO-poor diet -- dietary
sensitivity of impaired 5-HT system exposed by stress?
(Markus et al.,1998)
In stress-prone group only, CHO-
rich breakfast and lunch prevents:
• Post-stress increase in cortisol
release
• Post-stress increase in
depressed mood and reduced
vigour
• this diet improved cognitive
function in a stress-prone group
(Markus et al., 2000)
Also…
Stress-prone
Not Stress-prone
(measured by DPI-N)

PCOS 2009
Dr Leigh Gibson
Roehampton University
37
High-TRP
α
-lactalbumin increases functional 5-HT
activity in stress-prone subjects only
Stress-prone
Not Stress-prone (Markus et al., 2000)

PCOS 2009
Dr Leigh Gibson
Roehampton University
38
Foods as anti-stress, serotoninergic
anti-depressants?
(“Potatoes not Prozac”)
To increase serotonin function:
• Carbohydrate-rich
• Low in protein
• Stimulate insulin release
A good example?
CHOCOLATE
• But, delayed benefit (1-2 hrs)
• Reinforcement of learned desire?
‘Eurochocolate 2004’, Perugia

PCOS 2009
Dr Leigh Gibson
Roehampton University
39
Transient improvement in mood
on eating chocolate
Macht & Müller (2007)
• After a sad film, mood is
restored only for a few
minutes by eating
chocolate.
• Probably an effect of
sensory pleasure (and its
associations).
• Better (complete) mood
improvement is seen in
emotional eaters
-Practice or
disposition?
(cp. increased guilt after eating in
‘chocolate addicts’ (Macdiarmid &
Hetherington, 1995)

PCOS 2009
Dr Leigh Gibson
Roehampton University
40
Sweet/fatty ‘comfort’ food intake increases with increasing job
strain, but only in ‘stress-prone’ men (DPI Neuroticism)
Low High
Stress Proneness
0
10
20
30
40
50
60
70
Sweet/fatty Food Freq*
Low
Medium
High
Job Strain
*mean + SE: Choc + Cakes + Sweet biscs + Pastries + Ice cream /month.
Adjusted for BMI, Age, Education, Phys Act.
Mult. Regn. interaction, p<0.005 (transformed data; N=98)
(Gibson, Hamer, Steptoe & Wardle, 2008)

PCOS 2009
Dr Leigh Gibson
Roehampton University
41
High stress-reactive women ate more energy, and more
servings of sweet fatty snack food, when stressed
Epel et al. (2001)

PCOS 2009
Dr Leigh Gibson
Roehampton University
42
Cortisol response predicts daily snack
intake in women (Newman et al., 2007)
• Daily hassles linked to
snack intake in high
reactor women only.
• High reactors also
show stronger
association between
snacking and
emotional, restrained
and disinhibited eating.

PCOS 2009
Dr Leigh Gibson
Roehampton University
43
Snack choice in stressed binge
eaters (Goldfield et al, 2008)
• Reactivity based on
perceived stress.
• High-reactive binge eaters
chose unhealthy snacks
over fruit/veg when
stressed (computer task).
• Unaffected by restraint
status.

PCOS 2009
Dr Leigh Gibson
Roehampton University
44
Why Cortisol and LHPA axis?
Emotions
Appetite
+ Reward
Brain energy
supply
Macronutr.
metabolism
Adiposity
Stress
Cortisol

PCOS 2009
Dr Leigh Gibson
Roehampton University
45
Evidence linking stress, cortisol
and obesity
• Cortisol response to stress, and to
awakening, have been linked to abdominal
adiposity
(Marin et al, 1992; Moyer et al., 1994;
Rosmond et al., 1998; Epel et al., 2000; Steptoe et
al., 2004; Gluck et al., 2004).
• Poorer cardiovascular recovery from acute
stress predicted increased abdominal
adiposity over 3 years
(Steptoe & Wardle, 2005).

PCOS 2009
Dr Leigh Gibson
Roehampton University
46
Hypothal
CRH
Pituitary
ACTH
Adrenal
Cortex
Cortisol
-
-
CeA
HC
Metabolic Emotional
Stressors
Hypothalamic
Pituitary
Adrenal
Axis
+
Abdominal
fat stores
Insulin
-
CHRONIC STRESS MODEL
Dallman et al. (2003)
Comfort Foods
NPY?

PCOS 2009
Dr Leigh Gibson
Roehampton University
47
“The Selfish Brain”
(Peters et al., 2004, 2007)
Peters et al. (2007)
• The brain’s ‘stress
response’ prioritises
energy supply to
itself
• This includes the
drive to eat
• Normally, a
delicate balance
• Limbic HPA axis
may be key
regulator

PCOS 2009
Dr Leigh Gibson
Roehampton University
48
Chronic stress upsets the balance, encouraging
overeating and abdominal obesity
Adam & Epel
(2007)
Zandian et al.
(2007)
NB: similar effect from exercise!

PCOS 2009
Dr Leigh Gibson
Roehampton University
49
Peciña, Schulkin &
Berridge (2006)
CRF in N. Accumbens enhances
learned incentive salience for sugar cue
Stress may trigger ‘bingeing’ by enhancing
salience of cues to reward, via N. Acc CRF
(Overlap with
drug addiction?)

PCOS 2009
Dr Leigh Gibson
Roehampton University
50
Do prospective studies link stress to
obesity?
Vitaliano et al. (2002)
(prospective data from male AD carers)
.30 .39
Poor diet
Low activity
Psych
Distress
Chronic
Stress CHD
.50 .33 Metabolic
Syndrome

PCOS 2009
Dr Leigh Gibson
Roehampton University
51
Epidemiology of stress and obesity
• Stress due to neighbourhood disorder (in Texas)
predicts greater risk of obesity
(Burdette & Hill,
2008).
• Low SES middle-aged men and women at
greater risk of short-term weight gain
(Purslow et
al, 2008).
• Job stress predicts greater obesity (in London)
(Brunner, Chandola & Marmot, 2007).

PCOS 2009
Dr Leigh Gibson
Roehampton University
52
Meta-analysis of prospective studies
of stress and obesity
0.0090.03218
General life
stress
0.370.00811Job stress
0.330.00912Women
0.0370.02414Men
prN Studies
(Wardle, Chida, Gibson & Steptoe, submitted)

PCOS 2009
Dr Leigh Gibson
Roehampton University
53
Summary
• Comfort eating is preferentially for sweet fatty, energy
dense foods.
• Such foods stimulate opioid and other anti-stress
systems.
• Comfort eaters are more stress-prone, expressed
psychologically and via HPA axis activation.
• Increased CRF and cortisol release might drive
selection of comfort foods.
• Resultant central adiposity may restrain the HPA
axis: could this limit the stress-obesity relationship?
• Could cognitive restraint impair learning of a comfort
eating stress relief habit?