Deep inside your brain you have an internal “clock” that maintains awareness of your daily cycles and internal rhythms or patterns.
Your sleep/wake cycle, hunger/eating patterns and mental alertness patterns are examples of circadian rhythms that are kept in sync by your biological clock. These rhythms influence mood, stress levels, and even heart function and immunity. When working normally, our circadian rhythms help us maintain healthy schedules and habits.
Occasionally, however, our biological clocks can get out of sync, potentially causing disruption of our sleep patterns, alterations in mood, changes in hormone levels (cortisol, thyroid), and fluctuations in blood pressure. Some people have genetic predispositions or body chemistry abnormalities that account for their biological clocks’ tendencies to become more easily disrupted. But in most cases it is lifestyle choices that create the disruptions. Jet lag, shift work, sleep deprivation, and alcohol or drug consumption are all factors that affect our biological clocks, and these factors are under our control.
Problems Associated with Disruption of Normal Circadian Rhythms
If your circadian rhythms get out of sync, what kind of problems might you expect? The following conditions have been linked to a disruption of normal wake/sleep cycle.
Compromised immune function
Increased incidence of certain cancers
Problems with learning, memory, and muscle movement
Urs Albrecht, Associate Professor in the Department of Biology at University of Fribourg, Fribourg, Switzerland, reported in an article titled Circadian Clocks, published to the Handbook of Experimental Pharmacology, 217 (2013) that “there is evidence for a circadian basis for mood disorders”.
As an example, disruptions of clock genes are associated with a higher incidence of bipolar depression and greater insomnia as well as a decreased need for sleep by those experiencing bipolar mood disorders. He also noted that, “it appears that clock genes play an important role in limbic regions of the brain and influence the development of drug addiction.”
How Drug and Alcohol Use Affect our Biological Clocks
Dipak K.Sarkar, director of the endocrinology program and biomedical division of the Center of Alcohol Studies at Rutgers University, wrote in an article, Alcohol Consumption and the Body’s Biological Clock (Alcoholism: Clinical ; Experimental Research, May 2006) that “alcohol consumption has long-term adverse effects on the body’s internal clocks” and that “chronic drinking may increase the risk for sleep disturbances, depression, compromised immune function, and increased incidence of certain forms of cancers.”
Sarkar goes on to say that alcohol consumption can alter the molecular clock functions of certain hormone cells and immune cells, and it can also affect the ability of cells to “communicate” with one another. These changes set the stage for disrupted biological processes in tissues where timing plays a fundamental role, such as hormone function and immune function.
Additional evidence of the potential detrimental effects of drugs and alcohol on circadian rhythm function can be found in studies on the relationship between sleep disorders, detoxification and relapse.
A 2001 article in the American Journal of Psychiatry titled Insomnia, Self-Medication and Relapse to Alcoholism (M.D. Bower et al) reported that, “alcohol interferes with normal sleep patterns by disrupting particular neurotransmitters in the brain which control or regulate sleep.”
In addition, research found that cocaine use affects the brain chemical dopamine, which is involved with wakefulness, and typically reduces the amounts of both REM (rapid eye movement) and non-REM sleep. As a result, during detoxification, cocaine users often initially go through a period of excessive wakefulness.
Marijuana was also found to disrupt normal sleep patterns. THC, a chemical in marijuana, interacts with brain chemicals that are associated with sleep. The study found that “in larger doses, or with prolonged use, marijuana can cause insomnia and significantly reduced REM sleep.” Effects of REM sleep deprivation include anxiety, irritability, increased aggression, increased appetite and difficulty concentrating. In some cases a disturbance called REM sleep behavior disorder can occur. The main symptom of REM sleep behavior disorder is dream-enacting behaviors, sometimes violent, causing self-injury or injury to a bed partner.
Approximately 45% of all REM sleep behavior disorder cases are associated with alcohol or sedative-type drug withdrawal.