Ever wonder why the urge for an alcohol drink is more intense late in the afternoon or early evening? For many, a desire for a drink may seem simply to serve a need to relax after a long work day. Yet alcohol craving now appears to have a 24 hour circadian rhythm. Recall, circadian rhythm is our brain’s 24-hour internal clock that helps us stay alert or sleepy in response to light changes in our environment (Bass 2011). From an earlier study of 36 late adolescent drinkers, the investigators found that alcohol craving was increased during the evening hours, but much lower in the morning (Hister 2021). In a larger follow up study of 215 drinkers, age 21 to 35, data from cellphone contacts 6 times a day across 10 days documented maximum alcohol craving around 20:00, and lowest at 08:00. Prior alcohol consumption in the 30 days prior to the study led to higher levels of alcohol craving.

The link of alcohol craving to the circadian rhythm, of course, is complicated, invoking biology of melatonin and cortisol, as well as  body temperature, eating habits, digestion, and hormone release, all  governed by the superchiasmatic nucleus within the hypothalamus  (Bass, 2011, Hasler 2012). Yet this linkage may lead clinically to a focus on timing of interventions to curb alcohol craving and reduce drinking. 

James Woods |


1/4/2024