Caffeine as an Ingredient in Sugar Sweetened Beverages - Caffeine: Chemistry, Analysis, Function and Effects - page 25

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Figure 2.3

Caffeine's cycle of dependence. This figure describes the cycle of caffeine
dependence, moving between positive effects of caffeine following
ingestion and the onset of symptoms of withdrawal which are reversed
by consuming caffeine again.

reversed in their entirety. Reinforcing effects of caffeine have been demon-
strated through studies that investigated abstinence of caffeine in caffeine
consumers, whereby an increase in preference for caffeinated beverages was
identified (Hughes et al 1998; Juliano and Griffiths 2004). This evidence
supports some of the motivations of caffeine consumers to continue to
consume caffeinated beverages or foods. Re-dosing in caffeine consumers may
occur for the acute positive effects caffeine has on the body, to lead to a
reversal of withdrawal symptoms associated with caffeine abstinence, or for
taste preferences for caffeine (Figure 2.3).

2.2.2 Is Caffeine a Drug of Dependence?
In a study of 162 caffeine consumers, Hughes et al. reported 56% had a strong
desire or unsuccessful attempt to quit caffeine consumption, 50% spent a great
deal of time obtaining caffeine, 28% used more than intended, and 18%
suffered withdrawal symptoms (Hughes et al 1998). Although different
mechanisms of action are involved, drugs of dependence have a similar site
of action to that of caffeine. For this reason, and its ability to reverse
withdrawal effects, caffeine has been thought by some to be a drug of
dependence. Tolerance to the effects of caffeine has been demonstrated in
chronic users indicating its drug like properties. Caffeine users have also been