Caffeine is the most widely consumed drug in the world, with coffee representing a major source of intake. In my earlier book, Wonder Drugs, I did not include caffeine. Back then, in the 1980s, caffeine was considered a drink of abuse. I have since rethought my position, based on the latest evidence. For example, researchers have recently suggested regular consumption of moderate doses of coffee decreases risks for all-cause mortality and age-associated diseases (cardiovascular, stroke, cancer). Coffee intake preserves the main biological mechanisms of anti-aging and adults can safely consume 400 mg of caffeine each day, according to the Food and Drug Administration.
Benefits of Coffee Drinking
Multiple studies have found associations between regular coffee consumption and an increased lifespan. While the exact mechanisms are still being studied, coffee’s combined health benefits likely contribute to this effect. For example, regular coffee consumption is linked to reduced inflammation. In addition, coffee is abundant in antioxidants, such as chlorogenic acids, which help neutralize harmful cancer-causing free radicals in the body. By reducing oxidative stress, these antioxidants can slow cellular aging and decrease risks of chronic diseases. Chronic inflammation is also associated with various age-related diseases, including cardiovascular conditions and certain cancers. The anti-inflammatory properties of coffee may, therefore, contribute to healthier aging.
Studies indicate that coffee drinkers have a lower risk of developing neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Compounds in coffee may protect neurons from damage, supporting cognitive function as we age. Coffee consumption also has been associated with improved metabolic markers, such as better insulin sensitivity and a reduced risk of type 2 diabetes. Maintaining metabolic health is crucial for longevity and reducing age-related health issues. Moderate coffee intake also has been linked to a lower risk of heart disease. The bioactive compounds in coffee may improve blood vessel function and reduce the risk of arterial damage. Some research even suggests coffee may help protect human DNA from damage, preserving genetic information and promoting healthy cell function over time. The coffee lifespan benefit corresponds to an average increase of 1.8 more years of life.
“Caffeine, when consumed in moderation, can offer benefits like improved focus, alertness, and even enhanced cognitive function. It has also been linked to potential health perks, such as supporting metabolic health and reducing the risk of certain neurodegenerative diseases,” said Nicole Avena, Ph.D., of the Mt. Sinai School of Medicine and Princeton University.” She cautions, however, that “it’s important to be mindful of where your caffeine is coming from. Energy drinks, for example, can be loaded with added sugars and excess calories, which may counteract benefits of caffeine. Opting for sources like coffee or tea, without too much added sugar, is a smarter way to enjoy caffeine’s effects while supporting overall health.”
It’s important to note while these findings are promising, individual responses to coffee can vary. Factors such as genetics, existing health conditions, and lifestyle choices play significant roles in how coffee affects health.
How Much Caffeine Is in Decaf Coffee?
Despite widespread availability, various medical conditions necessitate caffeine-restricted diets. The Starbucks Decaffeinated Coffee Study by me and Bruce Goldberger revealed a surprising finding: Many popular brands of decaffeinated coffee still contained measurable amounts of caffeine—and sometimes significant quantities.
While trace amounts of caffeine are expected in decaffeinated coffee, since caffeine extraction is not 100% effective, the study shocked many consumers who assumed “decaf” meant “zero caffeine.” According to U.S. FDA regulations, coffee must be 97% caffeine-free to be labeled “decaf” in the U.S. European standards, however, require 99.9% caffeine removal.
Caffeine Dependence
Roland R. Griffiths, a prominent psychopharmacologist at Johns Hopkins University, made significant contributions to our understanding of caffeine’s effects, dependence, and withdrawal. He examined biological evidence for caffeine dependence, the prevalence of such dependence, and the clinical significance of caffeine use disorder—a valid diagnosis.
Griffiths also addressed the rising consumption of caffeinated energy drinks. His study discussed potential health risks associated with these beverages, particularly among adolescents and young adults, emphasizing the need for increased awareness and regulation. Some individuals struggle to reduce their caffeine consumption.
While caffeine can enhance alertness and well-being at lower doses, higher doses may lead to anxiety and insomnia—or worse. Red Bull, for example, contains 80 mg of caffeine per 8.4 oz; 5-Hour Energy contains 200mg per 2 oz shot; and Monster Energy, 160 mg per 16 oz. In 2023, the parents of a college student with a heart condition sued Panera Bread after the student died following the drinking of heavily caffeinated “charged” lemonade. The product was later withdrawn from the menu.
Regular caffeine consumption can lead to dependence, with withdrawal symptoms like headaches, fatigue, and irritability. Caffeine withdrawal is now an acknowledged clinical condition, characterized by specific symptoms that can impair daily functioning.
Why Isn’t Caffeine Sniffed, Snorted, or Injected Like Other Drugs?
While some have compared caffeine to cocaine or amphetamine, caffeine is almost never abused via snorting or injection, thus substantially reducing its potential as a drug of abuse. Caffeine is poorly water-soluble in its pure form, making it a bad candidate for injection. It also does not dissolve well in blood or mucus membranes, making snorting or injecting inefficient and painful. Cocaine and amphetamines are more lipophilic (fat-soluble), allowing for rapid absorption through nasal tissue.
Caffeine mainly works by blocking adenosine receptors, preventing drowsiness. It has a milder, slower stimulant effect compared to dopamine-releasing drugs like cocaine, which flood the brain with pleasure signals. Snorting or injecting caffeine would not significantly increase its euphoric effects, unlike when cocaine or meth is snorted or injected. In addition, snorting caffeine would cause severe nasal irritation and burning. Injecting caffeine could cause severe cardiac arrhythmias. Even when used in a hospital by prescription (e.g., intravenous caffeine for neonatal apnea), it is very carefully dosed to avoid toxicity.
Which Is Healthier: Coffee or Tea?
Consumers may argue whether coffee or tea is healthier, but it is not settled science. Coffee (higher caffeine, faster-acting) is likely better for alertness and memory. Tea is likely better for relaxation, and green tea may have additional benefits for both gastrointestinal and heart health. In addition, green tea is better for weight loss.
The Bottom Line
Caffeinated coffee has many apparent health benefits. Recent science has looked at coffee’s neuroprotective effects, and its effects on longevity and mortality. However, caffeine dependence and withdrawal are common, causing symptoms like headache, fatigue, or irritability. While generally not a health concern or problem, some physicians suggest adding caffeine to IV fluids or prescribing oral caffeine to prevent caffeine withdrawal in hospitalized patients. Most people don’t want to give up their morning coffee (or tea) but avoid drinking caffeinated beverages in the evening lest they find themselves jittery or having sleep problems. In choosing your caffeine source, coffee or tea is better than caffeinated soft drinks or energy drinks, which contain numerous extraneous chemicals.