370 CHAPTER 9
it does in adulthood and with decreased activity levels), that person’s weight set point
increases if the same number of calories is consumed. Figure 9. 5 shows the changes in
BMR of a typical woman and man as age increases from 10 to 80 years. Notice that the
BMR decreases more dramatically as the age of the person increases. Adolescents typi-
cally have a very high BMR and activity level and, therefore, a lower weight set point,
meaning they can eat far more than an adult of the same size and not gain weight. But
when that adolescent becomes an adult, the BMR begins to decline. Adults should reduce
the number of calories they consume and exercise most every day, but the tendency is
to eat more and move less as income levels and job demands increase. Even if the eat-
ing habits of the teenage years are simply maintained, excessive weight gain is not far
behind. (In some people, the excessive weight gain may be mostly “behind.”)
If you would like to calculate your own BMR, there are numerous Internet sites that
allow a person to enter data such as height, age, weight, and activity level. The BMR is
then automatically calculated according to a standard formula. Simply type “basal meta-
bolic rate calculator” into your Web search engine to find these sites.
SOCIAL COMPONENTS OF HUNGER People often eat when they are not really hungry.
There are all sorts of social cues that tell people to eat, such as the convention of eating
breakfast, lunch, and dinner at certain times. A large part of that “convention” is actually
the result of classical conditioning. to Learning Objective 5.2. The body becomes
conditioned to respond with the hunger reflex at certain times of the day; through asso-
ciation with the act of eating, those times of the day have become conditioned stimuli for
hunger. Sometimes a person who has just eaten a late breakfast will still “feel” hungry at
noon, simply because the clock says it’s time to eat. People also respond to the appeal of
food. How many times has someone finished a huge meal only to be tempted by that lus-
cious-looking cheesecake on the dessert cart? To see whether you have any implicit pref-
erences toward either healthy food or junk food, participate in the experiment Implicit
Association Test: Food. Simulate the Experiment, Implicit Association Test: Food
Food can also be used in times of stress as a comforting routine, an immediate
escape from whatever is unpleasant (Dallman et al., 2003). Rodin (1981, 1985) found that
the insulin levels that create hunger may actually increase before food is eaten (similar
10–18 19–30
AGES RANGE
31–60 61–80
Female (5½ ft.)
Male (6 ft.)
0
500
1000
1500
2000
1,770*
2,140
1,720 1,623
2,071
2500
*Numbers in the table represent the number of calories a person
needs to consume each day to maintain body weight (without exercise)
1,934
1,506
1,770
Figure 9.5 Average BMR for a Female and Male
Interactive
