Time Magazine has reported on a study conducted by the Harvard School of Public Health and published this month in The World Journal of Biological Psychiatry that suggests that coffee consumption may reduce the incidence of suicide. But coffee may come to suicide through a back entrance.
The coffee-drinking habits of over 200,000 people over a sixteen-year period were examined in the Harvard study. More particularly, the focus was on 43,599 men enrolled in the Health Professionals Follow-Up Study (HPFS) from 1988 to 2008, 73,820 women in the Nurses’ Health Study (NHS) from 1992 to 2008, and 91,005 women in the NHSII study, which encompassed the years of 1993 to 2007. By means of questionnaires sent every four years, caffeine consumption was calculated from several sources, including tea, caffeinated soft drinks, and chocolate. But coffee was the major wellspring of caffeine. Among the participants in the three studies there were 277 deaths from suicide.
Upon a review of the data it was determined that the risk of suicide for adults who drank two to four cups of caffeinated coffee per day was about half that of those who drank decaffeinated coffee or very little to none of the caffeinated kind. (Harvardgazette.)
These results mirror research in 2011 indicating that women who drink coffee cut their risk of depression by 15 percent. Michel Lucas, the head researcher of the Harvard study, surmised that caffeine may act as a mild anti-depressant. (The Huffington Post.)
Caffeine stimulates the central nervous system, the network of cells sending signals from one part of the body to another through the spinal cord. The stimulation causes greater alertness and energy. In addition, there is an influence exerted on the adrenal glands, which produce cortisol, the primary hormone for providing the body with a buffer during stressful times. Because caffeine accelerates cortisol production, and cortisol manufacture boosts serotonin, caffeine indirectly increases serotonin. This is why caffeine may induce a mildly elevated mood. Caffeine also rouses dopamine, which helps to regulate emotional responses. (LiveStrong.com)
A recent article in the New Yorker pointed out that caffeine has been found to increase energy and decrease fatigue, aid short-term memory, and enhance facilities of problem solving, decision making, and concentration. Caffeine quickly crosses the blood-brain barrier, a dynamic interface separating the brain from the circulatory system and protecting the central nervous system from potentially harmful chemicals. The blood-brain barrier also regulates the movement of molecules that maintain a stable environment. (Johns Hopkins University.) Caffeine overcomes these defenses and goes in to inhibit the activities of adenosine, a neurotransmitter that regulates some of the most basic functions of the brain’s sleep cycle. (LiveStrong.com.) In other words, tying up adenosine helps to keep us awake.
But, the New Yorker article continues, while caffeine aids in concentration, it does not permit the discursiveness that lets the mind take a break from its fastidious engagement. The diversion stimulates unconscious associative processing, in which we can perceive connections we would otherwise miss. Relenting our focus for a while, occupying ourselves with undemanding tasks, augments communication between the brain’s default mode network and its “higher” functions. This happens more readily when our minds are at rest. (The New Yorker.)
But coffee may eventually bring us back to suicidal thoughts.
A new edition of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM) refers to a condition known as “caffeine intoxication,” which involves such symptoms as restlessness, nervousness, excitement, diuresis, gastrointestinal disturbance, muscle twitching, rambling thought and speech and episodes of psychomotor agitation (unintentional motion). A new entry in the DSM is caffeine withdrawal, with its accompanying symptoms of fatigue, headache and difficulty focusing. (Time Magazine.)
Caffeine diminishes the quality of sleep and its efficient functioning. It limits the duration of stage-two sleep and the strength of delta-wave frequencies. This is significant when we consider the five stages of sleep and the corresponding electrical voltages emanating from the brain. Stage 1, the beginning of the sleep cycle, is a period of light sleep lasting about 5-10 minutes in which the brain produces a high amplitude of theta waves (4 to 7 hertz per second). In Stage 2, the brain generates bursts of rhythmic brain wave activity known as “sleep spindles.” This should continue for approximately 20 minutes, unless interrupted by the effects of substances like caffeine. The brain sends out delta waves (0.5 to 3 hertz per second) during stage 3 sleep. Stage 3 is a transitional period between light sleep and a very deep sleep. Stage 4 is “deep sleep” that extends for approximately 30 minutes. Dreams happen mostly during the fifth stage of sleep, which is accompanied by rapid eye movement (REM). We dream because of the inverse relationship between amplified brain activity and a relaxation of the voluntary muscles. In other words, we’re thinking furiously while we’re paralyzed, a condition that may be familiar to victims of lifetime paralysis. The REM stage starts about 90 minutes after we fall asleep, and can last up to an hour. These cycles of sleep can happen four or five times a night. (About.com; see also T. Schwartz, What Really Matters: Searching for Wisdom in America.) The negative consequences of caffeine on Stages 2 and 3 can thus be repeated and prolonged.
Other studies have also ascribed a diminution of the quality and efficiency of sleep to caffeine. Caffeine may multiply the number of times we awaken during the night. Sleep deprivation can diminish emotional intelligence, constructive thinking, and the ability to cope with stress. (The New Yorker.)
The beneficent impact of coffee consumption on suicidal inclinations, discerned in the Harvard study, may be, to some degree, disputable. A paper presented to the World Psychiatric Association International Congress in Florence, Italy in 2009 looked at the interrelationship between sleep problems and suicidal behaviors among 5,000 participants. Marcin Wojnar, a researcher at the University of Michigan in Ann Arbor, who led the study, said that people with two or more symptoms of sleep deprivation were 2.6 times more likely to report a suicide attempt than those with no complaints of insomnia. (Vidette Online, Illinois State University)
Of the 5,692 volunteers, 35% reported at least one of the three sleep disorder symptoms during the previous 12 months: waking up too early, having difficulty getting to sleep, and waking up repeatedly during the night.
People that repeatedly woke up too early in the morning over the preceding twelve months were doubly likely to have suicidal thoughts, 2.1 times more likely to plan to kill themselves, and 2.7 times more likely to attempt suicide than their well-rested peers.
Subjects with problems of falling asleep had a greater potential than healthy sleepers to make plans for taking their lives. Those who kept waking during the night and taking an hour or more to get back to sleep had an increased risk of contemplating or attempting suicide. (UK Guardian.)
In 2009, a team headed by Columbia University Medical Center researcher James Ganswisch studied data on more than15, 000 teenagers in the US. The data had been gathered by the National Institutes of Health. The team identified an interlinking of sleeplessness to depression and suicidal thoughts. (Adolescent Mood Disorders: Education, Intervention, Guidance.)
There is accumulating research supporting the close association of sleep disturbances and suicidal ideation and behaviors. Serotonergic neurotranmissions, it has been learned, are important factors in both sleep and suicide. (“Sleep Disturbances and Suicide Risk: a Review of the Literature,” Dove Medical Press.)
It takes little imagination to guess that of the three types of insomnia (transient, short term and chronic), chronic insomnia is most likely to bring on suicidal considerations, as well as causing other physical and mental problems.
Lack of sleep may negatively affect the functions of the frontal cortex of the brain controlling speech, memory and problem-solving by impairing the formation of nervous tissue and preventing the brain from renewing and rewiring itself. (C. S. Khan, “All about Sleep.”)
Fortunately, among the instigators of suicidal tendencies, sleep deprivation may be the easiest to treat by such means as cognitive behavior therapy. (Health Central.com)
Caffeine may give us a boost, but the exhilaration may actually lead to depression and suicidal thoughts. Coffee may be good for us or it may be a back door to suicide.
By: Tom Ukinski