koert van ittersum professor of marketing and consumer well-being learned when young is done when...

Koert van IttersumProfessor of Marketing and Consumer Well-being

Learned when young is done when young: Children's Portions & Obesity

2nd Annual

Healthwise Conference"Quality of Life""Quality of Life"

The Problem

The Mindful Marketer

The Mindful Marketer

The Mindful Marketer

The Mindless Consumer

The Mindless ConsumerVisual Illusions and Consumption

The Mindless ConsumerVisual Illusions and Consumption

Adults serving themselves OJ

Wansink and Van Ittersum (2003)

The Mindless ConsumerVisual Illusions and Consumption

Serving: F(1, 82) = 11.99, p < .05

Perception: F(1, 82) = 81.77, p < .01 N=89

Age=37.2, 22.4% F

Jazz Camp

Professional bartender serving drinks

Despite 6 years of bartending experience, professional bartenders served 20.5% more into short, wide glasses than tall elongated glasses (Wansink and Van Ittersum 2003)

The Mindless ConsumerVisual Illusions and Consumption

N=45

46.7% F

F(1, 33) = 29.83 p < .01

Childeren serving themselves OJ

Wansink and Van Ittersum (2003)

The Mindless ConsumerVisual Illusions and Consumption

N=97

Age=15.0, 54.6% F

Health and Fitness Camp

Serving: F(1, 90) = 93.72, p < .05

Perception: F(1, 90) = 3.83, p = .05

THE SIZE OF AMERICAN-MANUFACTURED PLATES APPEARS TO INCREASE FROM 1900 TO 2010

The Mindless ConsumerVisual Illusions and Consumption

Van Ittersum and Wansink (2012)

The Mindless ConsumerVisual Illusions and Consumption

The Mindless ConsumerVisual Illusions and Consumption

Wansink and Van Ittersum (2005)

Even when nutrition experts were given a larger bowl, they served themselves 31.0% more ice cream without being aware of it

Ouncesof ice cream

The Mindless ConsumerVisual Illusions and Consumption

N=85

68.2% F

Serving: F(1, 80) = 8.05, p < .01

Perception: F(1, 80) = 2.70, p = .10

Wansink and Van Ittersum (2005)

Adult jazz musicians served themselves 32,5% more cereal

Grams of cereal

The Mindless ConsumerVisual Illusions and Consumption

Serving: F(1, 80) = 16.54, p < .01

N=81

Age=37.2, 22.2% F

Jazz Camp

Van Ittersum and Wansink (2012)

The Mindless ConsumerVisual Illusions and Consumption

Larger Plates are Associated with More Food Being Served, Consumed, and Wasted in All-

You-Can-Eat Chinese Buffets

* p < .05, ** p < .01

800,5

1,216.9**

-739,1

-1,072.5**

61,4144.4**

-1.250

-750

-250

250

750

1.250

Amount served Amount consumed Amount wasted

Serving size (cm2 food)

Small plate (21.0 cm)

Large plate (26.5 cm)

The Mindless ConsumerVisual Illusions and Consumption

N=43

Age=40.7, 51.0% F

4 Chinese Buffets

Serving: F(1, 35) = 32.7, p < .01

Waste: F(1, 35) = 9.0, p < .01, Wansink and Van Ittersum (2013)

The Mindless ConsumerVisual Illusions and Consumption

Van Ittersum and Wansink (2012)

The Mindless ConsumerVisual Illusions and Consumption

Van Ittersum and Wansink (2012)

The Mindless ConsumerVisual Illusions and Consumption

Van Ittersum and Wansink (2012)

Larger bowls

Control bowl

Smaller bowls

Bowl 1 Bowl 2 Bowl 3 Bowl 4 Bowl 5 Bowl 6 Bowl 7

dtarget (cm) 9 9 9 9 9 9 9

dbowl (cm) 36 25.7 20 18 16.4 13.8 12

Diameter Ratio 0.25 0.35 0.45 0.50 0.55 0.65 0.75

# Participants 31 31 35 32 32 33 31

12.3%***13.1%***

5.0%**

-0.9%ns

-3.8%**

-11.5%***

-9.2%***

-10.4%***-10.8%***

-4.5%*

0.8%ns

6.3%***

12.1%***

8.9%***

-15,0%

-10,0%

-5,0%

0,0%

5,0%

10,0%

15,0%

Estimation bias Serving bias

% Bias Diameter

Ratio

The Mindless ConsumerVisual Illusions and Consumption

Van Ittersum and Wansink (2012)

The Mindless ConsumerVisual Illusions and Consumption

Van Ittersum and Wansink (2012)

Larger bowls

Control bowl

Smaller bowls

Bowl 1 Bowl 2 Bowl 3 Bowl 4 Bowl 5 Bowl 6 Bowl 7

dtarget (cm) 9 9 9 9 9 9 9

dbowl (cm) 36 25.7 20 18 16.4 13.8 12

Diameter Ratio 0.25 0.35 0.45 0.50 0.55 0.65 0.75

# Participants 31 31 35 32 32 33 31

12.3%***13.1%***

5.0%**

-0.9%ns

-3.8%**

-11.5%***

-9.2%***

-10.4%***-10.8%***

-4.5%*

0.8%ns

6.3%***

12.1%***

8.9%***

-15,0%

-10,0%

-5,0%

0,0%

5,0%

10,0%

15,0%

Estimation bias Serving bias

% Bias Diameter

Ratio

The Mindless ConsumerVisual Illusions and Consumption

Study: 2 serving tasks, 2 conditions

a) First serving in neutral bowl, second serving in biasing bowl (N=37)

b) First serving in biasing bowl, second serving in neutral bowl (N=98)

N=135Age=21.0, 48.9% F

Wansink and Van Ittersum (2013)

Larger Bowls

Control Bowl

Smaller Bowls

Bowl 1 Bowl 2 Bowl 3 Bowl 4 Bowl 5 Bowl 6 Bowl 7

1.8%ns

-.8%ns

0.3%ns

-0.6%ns

1.2%ns

.4%ns

4.2%**

5.5%**

1.4%ns

-1.2%ns

-3.3%**-2.4%*

-15,0%

-10,0%

-5,0%

0,0%

5,0%

10,0%

15,0%

% bias Diameter

ratio

2nd serving task 1st serving task

The Mindless ConsumerVisual Illusions and Consumption

First serving in neutral bowl, second serving in biasing bowl

Training does not eliminate plate-size induced serving biases

Wansink and Van Ittersum (2013)

Larger Bowls

Control Bowl

Smaller Bowls

Bowl 1 Bowl 2 Bowl 3 Bowl 4 Bowl 5 Bowl 6 Bowl 7

10.2%***

11.8%***

2.0%*

-3.3%*

-11.6%*** -11.3%***

4.4%***5.6%**

1.8%*

-2.7%*

-6.4%***-7.1%***

-15,0%

-10,0%

-5,0%

0,0%

5,0%

10,0%

15,0%

% bias

Diameter ratio

1st serving task 2nd serving task

The Mindless ConsumerVisual Illusions and Consumption

First serving in biasing bowl, second serving in neutral bowl

Plate-size induced serving biases change portion norms

Wansink and Van Ittersum (2013)

Teenagers

Van Ittersum and Wansink (2012)

Grams of cereal

The Mindless ConsumerVisual Illusions and Consumption

N=113

Age=11.5, 48.6% F

Health and Fitness Camp

Serving: F(1, 112) = 27.24 , p < .01

Plate-size induced serving biases change portion norms

Schoolkids – adult server

Wansink, Van Ittersum, and Payne (2014)

Grams of cereal + milk

The Mindless ConsumerVisual Illusions and Consumption

N=18

Age=8.3, 66.7% F

4 breakfasts, summer camp

Serving: F(1,17) = 15.2; p < .01

Waste: F(1,17) = 6.13; p < .05

Plate-size induced serving biases change portion norms

Toddlers – parent serves

Wansink, Van Ittersum, and Payne (2014)

Grams of cereal

The Mindless ConsumerVisual Illusions and Consumption

Serving: p < .001

N=69

Age=4.1, 50.0% F

Plate-size induced serving biases change portion norms

Learned when young is done when young: Children's Portions & Obesity