The effect of calorie information on food consumption


The (over)consumption of calories is one of the most important determinants of the obesity 

problem  in  Europe  and  the  United  States.  Governments  promote  the  consumption  of 

healthy alternatives and try to support consumers in making healthy choices, for instance by 

the introduction of the Nutritional Labeling and Education Act (NLEA) in the United States . 

The  NLEA  requires  manufacturers  to  provide  nutrition  information  on  the  packaging  of 

food  products.  In  a  similar  vein,  the  European  Commission  is  working  on  an  updated 

version of  its  regulation on food labeling, issued in December 2006. This regulation  defines

specific  nutritional  profiles  which  the  food  industry  must  comply  with  in  order  to  bear 

nutrition  or  health  claims.  Hence,  governments  want  to  make  sure  that  consumers  get 

reliable  information  on  food  and  eventually  make  more  healthy  choices.  Despite  these 

efforts, the obesity problem continues to increase in the United States and Europe. 

Jonathan Wilson is a business student at Tilburg University.  He  has been interested in the 

overconsumption  of  food  ever  since  he  has  read  Brian  Wansink’s  famous  study  with  the 

“bottomless bowls.” For this study, Wansink brought in 60 people for a free lunch and gave 

22 ounce bowls of soup to half, while the other half unknowingly got 22 ounce bowls that 

automatically  refilled  as  they  ate  (by  an  unseen  tube  under  the  table).  The  result:  those 

eating  from  the  bottomless  bowls  thought  they’d  eaten  the  same  amount  as  people  with 

regular bowls.  They actually consumed 73% more soup.  “The lesson is, don’t rely on your 

stomach to tell you when you’re full. It can lie,” Wansink reacted to the results of this study.

Together  with  his  thesis  supervisor,  Donald  Driver,  Jonathan  has  developed  a  series  of 

studies on the effects of Nutrition Labels  on people’s attitudes toward the product, buying

intentions, and  the perceived healthiness of food products.  The purpose of  his  latest study 

was to determine how the provision of objective calorie information on healthy food items 

influences people’s experience of hunger. 

Jonathan has developed  a  first draft of the method section of this study, which is detailed 

next.  The  method  section  of  a  paper  provides  the  methods  and  procedures  used  in  a 

research study.

The experiment: predictions

We compared hunger ratings between participants who sampled a healthy food item 

with  calorie  information  versus  participants  who  sampled  a  healthy  food  item 

without calorie information versus a “no sample” condition. We predicted that those 

who eat a healthy food item in the calorie information condition will subsequently 

report that they feel hungrier compared to those who eat a healthy food item in the 

no calorie information condition or those who do not eat the sample. 


Participants  and  design.  90  undergraduate  students  (38  women)  from  Tilburg 

University  were  randomly  assigned  to  the  conditions  of  a  3  (food  sample:  healthy 

with  calorie  information  vs.  healthy  without  calorie  information  vs.  no-sample) 

between-subjects design. The participants ranged in age from 18 to 37, with a median 

age of 22. The students received financial compensation (7 €) for their participation.

Procedure and Materials

Participants in the sampling conditions were recruited to participate in a taste test of 

a Muesli/granola bar that was unwrapped and contained no identifying information. 

Participants  in  the  no-sample  condition  were  invited  to  participate  in  a  marketing 

study rating the appearance of the bar. We asked all the participants in the sampling 

conditions  to  taste  a  sample  of  the  same  bar.  In  the  healthy  food item  with  calorie 

information condition, participants read that they were about to taste “a new health 

bar  containing  78  calories,  high  levels  of  vitamins  and  fiber,  and  no  artificial 

sweeteners.”  In  the  healthy  food  item  of  vitamins  and  fiber,  and  no  artificial 

sweeteners.” Participants in these conditions then had a 10 gram sample of the bar. 

Those in the no-sample condition did not complete the taste test.

Next,  in  order  to  assess  the  strength  of  the  motive  to  fulfill  their  appetite,  all 

participants rated how hungry they were at the present moment (7-point scale; 1 = 

not  at  all  hungry,  7  =  very  hungry).  Those  in  the  no-sample  condition  rated  their 

hunger but did not complete the taste test beforehand. After providing their hunger 

rating, they continued to rate how appealing they thought the bar was. 


1.  Is  the  purpose  of  Jonathan’s  study  exploratory,  descriptive,  or  is  hypothesistesting? Explain your choice.

2.  Is Jonathan’s study causal or correlational in nature? Explain your choice.

3.  What type of study is Jonathan’s study? Is it a field study, a field experiment, or 

a lab experiment? Explain your choice.

4.  What research strategy is Jonathan’s study? Explain your choice.

5.  Based  on  your  answer  to  question  four,  what  data  collection 

method(s)/instruments can Jonathan use? Explain your choice.

6.  What is the ‘unit of analysis’ of Jonathan’s study?

7.  Is Jonathan’s study cross-sectional or longitudinal in nature?