Transcript The Effects of Environmental Availability

Availability
(eventually) Beats
(rational) Cognition
(appealing)
Reading
• See the “Mindless Choosing” section in
Chapter 2 of Nudge
Availability
eventually Beats
rational Cognition
appealing
“Availability of …
energy dense
foods, is also a
major risk factor for
other consumption
related pathology,
such as certain
forms of obesity
and type-2
diabetes.”
Ahmed, S. (2005) Imbalance between drug and non-drug reward availability: A major risk factor for
addiction. European Journal of Pharmacology, 526, p. 11.
“alcohol problems
vary with alcohol
availability; this
body of evidence
is among the
strongest bodies of
evidence in
existence linking
health problems to
determinants.”
Mann, 2005, Availability as a law of
addiction. Addiction, 100, p. 924.
Availability
eventually Beats
rational Cognition
appealing
appealing
eventually
rational
Availability
Beats
Cognition
“Drinking and alcohol related problems can be affected
by restriction of the hours and days of alcohol purchasing
and of the numbers and types of alcohol outlets.”
Room, Babor, & Rehm, 2005, Alcohol and public health. The Lancet, 365, p. 526.
appealing
eventually
rational
Availability
Beats
Cognition
“Among environmental factors, drug
availability represents a major risk
factor. Increased drug availability can
precipitate the transition to addiction”
Ahmed, S. (2005) Imbalance between drug and non-drug reward availability: A major risk factor for
addiction. European Journal of Pharmacology, 526, p. 11.
Does physicians’
greater drug
knowledge
protect them
against greater
availability?
Physicians in the U.S. use
more opiates and
benzodiazepine than
others of the same age
Male physicians in Sweden
were more than twice as
likely to be using
tranquilizers as nonphysicians
“A higher percentage of
drug users among
physicians can be due to
the fact that self-treatment
is widespread”
Rosvold, E. (U. of Oslo), Vaglum, P. (U. of Oslo), Moum, T. (U. of Oslo), 1998, Use of minor
tranquilizers among Norwegian physicians. A nation-wide comparative study. Social Science &
Medicine, 46, 581-590.
Excessive availability increases consumption
I’ll have just a few…It’s not like I’m eating all 40!
Excessive
availability
increases
consumption
For any Scarface fans,
you may recall that
this environment did
not produce a happy
ending…
A lab experiment
Group A
5 unlimited bottles of water and
1 unlimited bottle of sugar water
Group B
1 unlimited bottle of water and
5 unlimited bottles of sugar water
a) Group A consumed more sugar?
b) Group B consumed more sugar?
c) No difference?
ml Sugar Water Consumed
Excessive availability increases consumption
55
50
45
40
1 water 5 sugar
5 water 1 sugar
35
30
25
4
8 12 16 20 24 28 32 36
Days
Tordoff, M. G. (2002) Obesity by choice: The powerful influence of nutrient availability on nutrient intake.
American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, 282, 1536-1539.
Excessive availability increases consumption
Group A
Average fat content of rats after
36 days: 57 grams
Group B
Average fat content of rats after
36 days: 76 grams
Both groups had unlimited access to
Purina rodent chow during the test.
Excessive availability increases consumption
Any relevance
for humans?
What about alcohol?
Group A
5 unlimited bottles of water and
1 unlimited bottle of 10% alcohol
Group B
1 unlimited bottle of water and
5 unlimited bottles of 10% alcohol
Did it make any
difference?
Excessive availability increases
consumption
Group A
Alcohol intake grams per kilogram
of mouse body weight: 9.4
Group B
Alcohol intake grams per kilogram
of mouse body weight: 23.4
What about with different ratios?
What about a different breed?
What about a rat instead of mouse?
Excessive availability increases
consumption
Alcohol as a % of total liquid intake
Mice
Rats
Unlimited bottles
(129x1/Svj)
1 alcohol vs. 5 water
9%
3%
2 alcohol vs. 4 water
16%
7%
3 alcohol vs. 3 water
24%
15%
4 alcohol vs. 2 water
32%
16%
5 alcohol vs. 1 water
42%
31%
Tordoff, M. G., & Bachmanov, A. A. (2003) Influence of the number of alcohol and water bottles on murine
alcohol intake. Alcoholism: Clinical and Experimental Research, 27(4), 600-606.
“Large
packages,
plates, and
serving bowls…
have all been
shown to
increase how
much a person
serves and
consumes by
15% to 45%.”
B. Wansink (Cornell), D. Just (Cornell), & C. Payne (New Mexico State U), 2009, Mindless eating and health heuristics for the
irrational. American Economic Review, 2009, 99(2), 165-169.
Experiment with Free Popcorn at a Movie Theatre
One
group got
240 g
buckets
One
group got
120 g
buckets
If nobody finished all of the popcorn, did container size still matter?
Even though no one finished all of the
popcorn, bigger portions → more eaten
Group with medium
buckets consumed 58.9
grams on average.
Group with large buckets
consumed 85.6 grams on
average.
Another group was given 14day old popcorn in medium
and large buckets.
“This popcorn tasted good”
(1=strongly disagree; 9=strongly agree)
Medium container: fresh = 7.7
Large container:
fresh = 6.8
old = 3.9
old = 2.2
Did people eat more bad popcorn just because it was
in a bigger container?
Bigger portions of bad popcorn = more eaten
Group with medium buckets
of 14-day old popcorn
consumed 38.0 grams.
Group with large buckets
of 14-day old popcorn
consumed 50.8 grams.
Wansink, B. & Kim, J. (2005) Bad popcorn in big buckets: Portion size can influence intake as much as taste.
Journal of Nutrition Education and Behavior, 37(5), 242-245.
Size v. Taste
90
Smaller portions taste better. Yet people eat more when
offered more.
80
Grams Eaten
70
60
50
40
30
20
10
6.8
Taste
Rating
7.7
Taste
Rating
2.2
Taste
Rating
3.9
Taste
Rating
Large Stale
Med Stale
0
Large Fresh Med Fresh
The misperceived effects of availability
“In one study, unknowing diners
were served tomato soup in
bowls that were refilled
through concealed tubing that
ran through the table and into
the bottom of the bowls.
People eating from these
“bottomless” bowls consumed
73% more soup than those
eating from normal bowls but
estimated that they ate only 4.8
calories more.”
B. Wansink (Cornell) & J. Sobal (Cornell), 2007, Mindless eating: The 200 daily food decisions we overlook.
Environment & Behavior, 39(1), 106-123, p. 109.
Excessive availability and consumption
In a study of 10 weight loss techniques, the most
effective was using smaller, 10-inch, plates
B. Wansink (Cornell), D. Just (Cornell), & C. Payne (New Mexico State U), 2009, Mindless eating and health
heuristics for the irrational. American Economic Review, 2009, 99(2), 165-169.
In the previous study, not
eating with the TV on was
the second most effective
technique for weight loss.
Why might food
availability during TV
watching be
especially relevant
according to the dualself approach?
B. Wansink (Cornell), D. Just (Cornell), & C. Payne (New Mexico State U), 2009, Mindless eating and health
heuristics for the irrational. American Economic Review, 2009, 99(2), 165-169.
Study of 10 weight loss techniques used by real
world volunteers. The two most effect techniques
changed only the eating environment.
METHOD
Lbs. of Monthly Weight Loss
Use ten-inch plates for dinner
−1.93
Don’t eat with the TV on
−1.58
Eat fruit before snacking
−1.11
Eat a hot breakfast
−1.07
Eat vegetables and salad first
−1.05
Use the half-plate rule
−0.60
Store produce on middle refrigerator shelf −0.47
Limit snacks to three bites
−0.29
Brush teeth instead of snacking
+0.18
Eat oatmeal for breakfast
+0.83
B. Wansink (Cornell), D. Just (Cornell), & C. Payne (New Mexico State U), 2009, Mindless eating and health
heuristics for the irrational. American Economic Review, 2009, 99(2), 165-169.
Effects of knowledge…
• MBA students had 90 minute class to prove that if they
snacked from gallon bowls of Chex Mix they would eat
more than if they snacked from half-gallon bowls.
• At a Super Bowl party six weeks later, half were directed
to a buffet table with two one-gallon bowls of Chex Mix,
the other to a buffet table with four ½ gallon bowls.
• Did information prevent the bigger bowls from having
an effect?
80
74.8
Avg. Grams Eaten
70
60
50
40
47.8
30
20
10
0
Group A: Four 1/2 Gallon Group B: Two 1 Gallon
Bowls
Bowls
B Wansink, & MM Cheney (2005) Journal of the American Medical Association, 293(14), 1727-1728; B.
Wansink, D. Just, & C. Payne (2009) American Economic Review, 2009, 99(2), 165-169.
The result of your knowledge…
80
70
60
Grams Eaten
When asked afterwards if
they believed the size of the
serving bowls influenced
them, the students said
“no.”
50
40
30
20
10
0
1/2 Gallon
Bowls
1 Gallon
Bowls
B Wansink, & MM Cheney (2005) Journal of the American Medical Association, 293(14), 1727-1728; B.
Wansink, D. Just, & C. Payne (2009) American Economic Review, 2009, 99(2), 165-169.
You watch TV.
I’ll eat.
Long-term
Patient
Planner
Impartial spectator
Deliberative
Cold state
Short-term
Impulsive
Doer
Passions
Affective/Visceral
Hot state
The size of this bowl has
nothing to do with how
much we should eat.
Brian Wansink
• YouTube
• Radio interview
WNYC
• Radio interview
NPR
• http://www.mindless
eating.org/
Availability beats cognition even when…
You know about the effects of environment on your decisions
You don’t believe the environment is changing your decisions
Your KNOWLEDGE of the impact of environment
on your behavior
and your BELIEF about the impact of
environment on your behavior
doesn’t CHANGE the impact of the
environment on your behavior.
So, what can
we do?
1. Whether we admit it
or not, more
knowledge won’t
change the impact of
environment on our
behaviors.
2. But, changing our
environment can
change our behaviors.
We can focus more
on choosing our
environment!
So why don’t we choose our
environment to match our goals?
Hyperbolic discounting [We will
make better choices in the future]
Projection bias [The “rider” will always
be in control]
Diversification bias [We want
maximum options]
I would like to
reduce the
amount of sugar
I eat, but I have
problems with
self-control
because I really
like sweets.
For health
reasons, I
would like to
increase the
amount of raw
vegetables, like
carrots and
celery, I eat.
They don’t
taste bad, but
they aren’t that
exciting, either.
What practical suggestions can you think of to
help each person by employing the principal of
“availability beats cognition”?