Caffeine is the most frequently consumed, socially acceptable, mood altering drug in the world. The primary delivery system for this drug is coffee, and the habitual use of coffee to mask exhaustion, wake up in the morning, stay alert, and prop up physical performance throughout the day makes coffee the most popular beverage in the world after water with over 2 billion cups of coffee  consumed daily worldwide. 

A typical 12 ounce cup of coffee has about 140-150 mg of caffeine, with some specialty, brand-named brewed coffees providing as much as 200-250 mg per cup,  compared to 45-75 mg in a cup of caffeinated green or black tea.  Decaffeinated coffee has less than 10 mg of caffeine per cup. Caffeine is a member of a chemical family called methylxanthines. It is metabolized in the liver into other xanthines (paraxanthine, theobromine and theophylline) that can affect the cardiovascular system, increase the contraction of smooth muscle in your stomach and intestines, increase urination and promote potential toxic effects in the body. (1) Caffeine is rapidly absorbed into all body tissues and easily crosses the protective vascular barriers of the brain and placenta. And since pregnancy decreases caffeine excretion, caffeine and its metabolites can accumulate excessively, cross the placental barrier and exert potential toxic effects on mother and developing fetus. (2) As  a result, it is best for women to avoid coffee during pregnancy.

While there are studies suggesting that caffeine can restrict blood flow to the heart and brain (3)(4), a number of reports demonstrate potential benefits of coffee on the cardiovascular, muscular, and central nervous systems, suggesting that the regular intake of coffee may be fine for adults. However, you should always recognize that drug “benefits” are often equated with “symptom suppression” and do not typically address the basic requirements of health or the true causes of disease. . Only healthy lifestyle choices of whole plant food nutrition, exercise, stress management, adequate sleep, water intake, fresh air and sunshine are the fundamental  requirements of health that also prevent and reverse the  causes of dysfunction and disease. Any perceived “benefits” of coffee/caffeine must be considered in the context of the evidence of negative effects to more effectively bring the bigger picture of coffee’s impact on your health into better focus.  

Impact on the  Cardiovascular System

A large study of  adult men and women ages 40-69 conducted over a 12 year period suggested that 2-3 cups of coffee (decaffeinated, ground, or instant) promoted the greatest reduction of risk for cardiovascular disease (reductions of 6%, 20% and 9% respectively) and death from any cause ( 14%, 27%  and 11% respectively). Only ground and instant coffees were associated with a reduction in the risk of arrhythmias including atrial fibrillation (17% and 12% respectively). (5)  While these data suggest that moderate amounts of coffee, including decaffeinated coffee, may be considered a part of a routine health program, it should be noted that these studies were poorly controlled for dietary factors (animal/processed food vs. whole plant nutrition) that play a major role in the initiation and progression of cardiovascular disease, including a failure to adjust for milk, creamers and sugar consumption. Caffeine causes anxiety, discomfort and a number of other disturbances in a large number of people, and since whole plant food nutrition, exercise and stress management have the greatest impact on preventing and reversing cardiovascular disease, it is questionable to recommend coffee as a routine part of any heart healthy program. 

Coffee causes an excitation of the brain, and toxic stress,  that triggers an emergency  stress response (“fight or flight”) provoking the release of cortisol and adrenaline from the adrenal gland. It has been suggested that high levels of circulating adrenaline can cause abnormal changes in the rate and rhythm of the heart. (6) However, additional research has shown that even though adrenaline is significantly increased by coffee consumption, even moderate to high levels of caffeine intake did not increase the risk of cardiac arrhythmias, increased heart rate (tachycardia) and cardiac mortality unless toxic levels of caffeine were achieved by consuming more than 9 cups of coffee a day. (7)

In contrast, other studies have shown that by blocking the dilating effect of adenosine, a neuromodulator/neurotransmitter, the caffeine found in 2-3 cups of coffee can constrict and increase the resistance of blood vessels to elevate both systolic and diastolic blood pressure in men and women with normal or high blood pressure. (8) Even lower amounts of caffeine (300 mg, equivalent to 1-2 cups of coffee) significantly increased systolic pressure 6-12 points,  and diastolic pressure 3-5 points. (9)

Impact on the Brain and Nervous System

The habitual consumption of coffee has been associated with a reduced risk of chronic, degenerative diseases in the brain and nervous system. People drinking 3-5 cups of coffee in midlife had the lowest risk of dementia and Alzheimer’s disease in later life compared to people drinking little to no coffee. (10) Unfortunately, these studies did not effectively control and evaluate coffee and non-coffee drinkers for factors that significantly affect the progression of blood vessel/nerve cell damage associated with Alzheimer’s disease (oxidized cholesterol, saturated/trans fats, AGE toxicity, homocysteine) that are common in a diet of animal based/processed food compared to whole plant food nutrition. Furthermore, while it has been suggested that coffee enhances cognitive performance, alertness and wakefulness (11), a number of studies indicate that the cognitive benefits are more accurately an indication of relief from caffeine withdrawal symptoms rather than true cognitive improvement. (12)(13) Substantial clinical experience has shown that when habitual coffee consumers abruptly stop caffeine intake, it can be one of the worst drug withdrawals there is, often including headache, anxiety, pain, nausea, and vomiting. Consistent with this clinical experience, abstinence from moderate, habitual use of caffeine (100 mg  per day ), typically found in just a single cup of coffee,  was shown to cause symptoms of withdrawal dominated by headaches and fatigue that manifested after 12-24 hours, peaked at 24-48 hours and could persist for as long as a  week. (14)(15)  

Low dose caffeine consumption in one cup of coffee (100 or 150 mg) in the morning was followed by afternoon withdrawal responses including  greater sleepiness, lower mental alertness, poor motor performance and slow reaction time for simple tasks, as well as decreased ability on recognition memory tasks. Follow up caffeine consumption in the afternoon improved these measures in higher, habitual coffee users but did not improve anything but sleepiness in people typically consuming none to small amounts of caffeine. However, it was suggested that the failure of coffee to improve mental alertness and performance in low caffeine users was due to a substantial  increase  of anxiety and jitteriness caused by caffeine and offset any reversal of sleepiness. (16)

Caffeine has also been found to reduce both the motor symptoms/tremors and the classic loss of dopamine producing neurons  in Parkinson’s disease. (17) Consistent with these observations, coffee consumption was associated with a 1/3 lower risk of developing Parkinson’s and providing Parkinson’s patients with caffeine equivalent of 2 daily cups of coffee significantly improved movement symptoms within 3 weeks although there was some question about the duration of these benefits. Yet, based on a number of collected studies, coffee consumption may be associated with a small reduction of overall mortality and premature death for each daily cup of coffee consumed. (18)  

People of all ages , especially young adults and athletes, typically associate coffee/caffeine with enhanced performance of the normal activities of daily living as well as athletic events.  However, caffeine can elicit dose-dependent positive or negative effects on muscular response and performance, and the anxiety inducing effects of habitual coffee intake are well established. (19) Lower dose caffeine (250 mg ) equivalent to 1-2 cups of coffee was associated with enhanced response time and agility of simple motor tasks, and positive subjective states (elation, peacefulness and pleasantness), while higher doses (500 mg) equivalent to 3+ cups of coffee promoted less performance enhancement as well as unpleasant tension, nervousness, anxiety , irritability, nausea, heart palpitations and restlessness. (20) 

Brain Reward and Addiction

Coffee affects your natural brain reward and pleasure response that relies on the release of the neurotransmitter, dopamine. The inhibitory modulator adenosine helps orchestrate our experience of pleasure by blocking and modifying the release of dopamine. Since caffeine blocks the action of adenosine and interferes with adenosine’s ability to inhibit dopamine release, it promotes  the excessive release of dopamine in brain areas that are primarily responsible for our experience of pleasure. This interaction is fundamentally responsible for any stimulatory or pleasurable effects of coffee consumption. (21)

However, any substance or behavior that can manipulate brain reward can promote a debilitating pleasure trap with subsequent disturbing and painful abstinence withdrawal symptoms. Craving and potential relapse are key features in the progression of substance abuse/dependency. Coffee use can often become abusive and addictive by provoking an uncontrolled urge to consume more consistent, large amounts of caffeine, including multiple sources of caffeine containing products, without regard for safety issues or detrimental health outcomes. 

Unfortunately, coffee/caffeine use is not diagnosed as a “substance use disorder” because it is not viewed as an intoxicating drug. But make no mistake, it is mood altering and can elicit toxic and addictive effects. Both adults and adolescents who consume large amounts of caffeine report psychiatric symptoms and adverse changes in behavior. Both the American Psychiatric Association and the World Health Organization recognize caffeine intoxication as a clinical syndrome that includes anxiety, restlessness, insomnia, gastrointestinal disturbances, tremors, rapid heart beat, and psychomotor agitation. (22)(23)

A Hidden Energy Crisis

Only plants can capture the energy of the sun to produce glucose that is combined with the oxygen you breathe, in the energy factories of your cells (mitochondria), to provide all the energy you need. Coffee/caffeine is not a nutrient or a biological requirement of life and health and does not promote or support natural energy production. In fact, the impact of coffee on your body energy and hormonal  system speaks to the very heart of our fatigued culture and the insidious effects of coffee. 

With the relentless consumption of energy sapping processed junk food (60-70% of the American diet ) and cooked, processed animal products (over 30% of the average diet), the glaring deficiency of energy rich whole natural plant foods, rampant sedentary behavior, sleep deprivation, and overwhelming chronic stress from demands/pressures of family, work, financial and social responsibilities, we are in the midst of a devastating energy crisis. Unfortunately, all too often, we approach this epidemic of exhaustion with rampant stimulant abuse from  coffee and caffeine in all its forms, instead of addressing  the profound causes of exhaustion stemming from abusive lifestyle choices. 

However, it is imperative to realize that while coffee may  elicit an initial perceived experience of energy stimulation,  it actually reinforces underlying exhaustion and depression. Whenever you stimulate the body with any form of chemical stimulation, that is only the initial effect. As your body processes, metabolizes, and handles these substances, you have no choice but to crash to the same extent that you were stimulated. Whatever goes up has to come down with equal and opposite force.  But most people are oblivious to this roller coaster of stimulation and depression, and are distracting themselves from the true causes of  their exhaustion while continuing to opt for an ephemeral illusion of energy. 

Coffee also provokes overstimulation and potential rebound exhaustion of the adrenal and thyroid glands promoting chronic stress, disturbances in blood sugar regulation, sugar craving, difficulties losing weight and reactive fat and weight gain. When you remove caffeine from your life, the withdrawal symptoms of pain, discomfort, and detoxification are all working to promote healing and recovery. Under these circumstances, what you are confronting is who you really are, which is an exhausted and toxic human being, and sooner rather than later it is essential  to confront the reality of what is and not just dance around and mask the true causes of fatigue, depression and exhaustion . 

 By making a concerted effort to eliminate factors of exhaustion, improve your nutrition  and lifestyle choices,  and manage the stress and demands of your life more successfully, you will increase your own energy and improve your quality of life and health. As you recover and generate your own power and energy, you will free yourself from the shackles of dependency and caffeine use/abuse. 

Impact on Sleep

There is only one remedy for exhaustion and that is sleep. Sleep is a restorative, regenerative process that replenishes your energy reserve and promotes mind-body healing and recovery. Unfortunately, this essential  biological requirement eludes so many of us and has become a significant deficiency in our hectic culture. It is estimated that transient insomnia affects 80 percent of the population, while 15 percent of us suffer with chronic insomnia.(24) Sleep deficiency promotes chronic stress, insulin resistance, obesity, type 2 diabetes and heart disease. Caffeine has significant adverse effects on healthy sleep. The neurotransmitter adenosine is also released in the brain to ease you into sleep. Since caffeine antagonizes the effects of adenosine, it interferes with normal, healthy sleep cycles. And since caffeine has a long half-life in your system, it can take many hours for the caffeine that you have consumed at any time in your day to be eliminated from the body. People receiving moderate doses of caffeine at bedtime and 3 and 6 hours before bedtime had significant sleep disturbances suggesting that if you do consume any coffee you should refrain from caffeine use a minimum of 6 hours before bedtime. (25)  In addition, since caffeine provokes the release of the stress chemicals, cortisol and adrenaline, it establishes and maintains a fight or flight stress response that will compound the stress of your day and make it impossible for your brain to quiet down at bedtime and achieve the peace and relaxation it needs to ease into restful sleep.

While some studies suggest that moderate use of coffee may have some limited, questionable benefits, it’s potential adverse effects are significant and must always be considered. Caffeine is not a fundamental health or nutritional requirement and significant health benefits are more accurately and effectively promoted by whole plant nutrition and other lifestyle choices that respect and highlight the basic requirements of life and health. As a result, the routine or habitual routine use of coffee has no place in any healthy living program and should be avoided.  

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