Why Coffee Might Make You Feel Unwell

Quick answer

• Coffee’s stimulating effects can lead to jitters, anxiety, or digestive upset for some individuals.
• The caffeine content varies, and sensitivity to it differs greatly from person to person.
• Acidity in coffee can trigger heartburn or stomach discomfort, especially on an empty stomach.
• Additives like sugar, cream, or artificial sweeteners can also contribute to negative feelings.
• Underlying health conditions may be exacerbated by coffee consumption.
• Timing of consumption, particularly close to bedtime, can disrupt sleep and impact overall well-being.

Key terms and definitions

• Caffeine: A natural stimulant found in coffee beans that affects the central nervous system.
• Acidity: Refers to the tart or tangy taste in coffee, which can also impact stomach pH.
• Digestive Upset: A broad term for discomfort in the stomach or intestines, such as bloating, gas, or nausea.
• Anxiety: A feeling of worry, nervousness, or unease, which can be amplified by caffeine for sensitive individuals.
• Jitters: A physical sensation of trembling or shakiness, often associated with consuming too much caffeine.
• Sleep Disruption: Interference with normal sleep patterns, leading to difficulty falling asleep or staying asleep.
• Gastroesophageal Reflux Disease (GERD): A chronic digestive disease where stomach acid or bile irritates the food pipe lining.
• Additives: Ingredients such as milk, cream, sugar, syrups, or artificial sweeteners added to coffee.
• Withdrawal Symptoms: Physical and mental effects experienced when a regular consumer of caffeine stops or significantly reduces intake.
• Individual Sensitivity: The unique way a person’s body reacts to a substance like caffeine, which can vary widely.

How it works

• Coffee contains caffeine, a stimulant that blocks adenosine, a neurotransmitter that promotes relaxation and sleepiness.
• This blockage leads to increased alertness and reduced perception of fatigue.
• Caffeine also stimulates the release of adrenaline, the “fight or flight” hormone, which can cause increased heart rate and blood pressure.
• For some, this adrenaline surge can manifest as anxiety or jitters.
• Coffee’s acidity can relax the lower esophageal sphincter, allowing stomach acid to back up into the esophagus.
• It can also increase stomach acid production, potentially leading to indigestion.
• The act of drinking a hot beverage can also stimulate bowel movements for some individuals.
• Certain compounds in coffee may influence the gut microbiome, though research is ongoing.
• The diuretic effect of caffeine, though often mild, can contribute to dehydration if fluid intake isn’t sufficient.
• The brain’s reward pathways can be activated by coffee, contributing to its habit-forming nature.

What affects the result

• Caffeine Content: Darker roasts generally have slightly less caffeine than lighter roasts, but the brewing method significantly impacts extraction.
• Individual Caffeine Sensitivity: Genetic factors and regular consumption habits determine how quickly your body metabolizes caffeine.
• Coffee Acidity: The pH level of the coffee, influenced by bean origin, roast level, and brewing method, can affect stomach irritation.
• Brewing Method: Drip coffee, espresso, cold brew, and French press all extract different compounds and concentrations of caffeine and acids.
• Grind Size: Too fine a grind can lead to over-extraction and bitterness, while too coarse a grind can result in under-extraction and weakness.
• Water Temperature: Water that is too hot can scorch the grounds, leading to bitter flavors, while water that is too cool may not extract enough flavor.
• Coffee Freshness: Stale coffee beans lose volatile aromatic compounds, leading to a less flavorful and potentially more bitter cup.
• Additives and Sweeteners: Sugar, artificial sweeteners, dairy, or non-dairy creamers can contribute to digestive issues or sugar spikes.
• Timing of Consumption: Drinking coffee too close to bedtime can interfere with sleep quality, leading to daytime fatigue.
• Empty Stomach: Consuming coffee on an empty stomach can intensify its acidic effects and caffeine’s impact on the digestive system.
• Amount Consumed: Drinking excessive amounts of coffee is a direct cause of many negative side effects.
• Underlying Health Conditions: Pre-existing conditions like GERD, anxiety disorders, or irritable bowel syndrome can be aggravated by coffee.

Pros, cons, and when it matters

• Pro: Increased Alertness: Coffee can significantly improve focus and reduce fatigue, beneficial for tasks requiring concentration.
• Con: Jitters and Anxiety: For sensitive individuals, caffeine can trigger or worsen feelings of nervousness and restlessness.
• Pro: Antioxidant Properties: Coffee contains antioxidants that may contribute to long-term health benefits.
• Con: Digestive Issues: Acidity and caffeine can cause stomach upset, heartburn, or bowel irregularities for some.
• Pro: Improved Physical Performance: Caffeine can enhance athletic performance by mobilizing fatty acids from fat tissues.
• Con: Sleep Disruption: Consuming coffee late in the day can lead to insomnia and poor sleep quality.
• Pro: Social Ritual: The act of preparing and sharing coffee can be a positive social or personal ritual.
• Con: Dependence and Withdrawal: Regular high intake can lead to caffeine dependence, with withdrawal symptoms like headaches and irritability upon cessation.
• Pro: Flavor and Enjoyment: Many people simply enjoy the taste and aroma of coffee as a daily pleasure.
• Con: Exacerbation of Health Conditions: Coffee can worsen symptoms for individuals with conditions like GERD, anxiety disorders, or heart arrhythmias.
• Pro: Potential Cognitive Benefits: Some studies suggest a link between coffee consumption and a reduced risk of certain neurodegenerative diseases.
• Con: Cost: Daily consumption, especially of specialty coffees or at cafes, can become a significant expense.

Common misconceptions

• Myth: All coffee is highly acidic. While coffee is acidic, the perceived acidity in taste varies greatly by bean, roast, and brewing method. Cold brew, for example, is often less acidic.
• Myth: Dark roast coffee has more caffeine. Generally, lighter roasts have slightly more caffeine by volume because the beans are denser. However, brewing methods can alter this significantly.
• Myth: Coffee directly causes ulcers. While coffee can irritate existing ulcers or GERD symptoms, it is not a direct cause of ulcer formation.
• Myth: You can “sweat out” caffeine. Caffeine is metabolized by the liver, and while hydration is important, sweating does not eliminate it from your system.
• Myth: Coffee is dehydrating. While caffeine is a mild diuretic, the water in coffee typically offsets this effect for moderate consumers.
• Myth: Adding milk or cream neutralizes caffeine. Milk or cream does not reduce the amount of caffeine in your coffee; it only alters the taste and mouthfeel.
• Myth: Coffee addiction is a serious health problem. While caffeine dependence is real, it’s generally considered less severe than addiction to other substances, with manageable withdrawal symptoms.
• Myth: Instant coffee is completely different from brewed coffee. While the processing differs, both contain caffeine and other compounds, though the flavor profile and extraction are distinct.
• Myth: Coffee is bad for everyone’s heart. For most healthy individuals, moderate coffee consumption does not negatively impact heart health and may even offer some protective benefits.
• Myth: Cold brew is caffeine-free. Cold brew is still coffee and contains caffeine, often in higher concentrations than hot-brewed coffee due to the higher coffee-to-water ratio used.

FAQ

Q: Why do I feel jittery after drinking coffee?

A: This is often due to caffeine’s stimulant effects. It increases adrenaline, which can lead to a racing heart, nervousness, and shakiness, especially if you are sensitive to caffeine or consume a large amount.

Q: Can coffee make my stomach hurt?

A: Yes, coffee can cause stomach discomfort for several reasons. Its acidity can irritate the stomach lining, and it can also stimulate the production of stomach acid, potentially worsening heartburn or indigestion.

Q: Is it normal to have trouble sleeping after drinking coffee?

A: Absolutely. Caffeine is a stimulant that blocks adenosine, a sleep-promoting chemical. If consumed too close to bedtime, it can significantly interfere with your ability to fall asleep and stay asleep.

Q: Does the type of coffee maker matter for how it makes me feel?

A: Yes, different brewing methods can affect the final cup. For example, cold brew is often less acidic and may be gentler on the stomach than hot-brewed coffee, and espresso has a higher caffeine concentration per volume.

Q: What if I feel unwell after drinking decaf coffee?

A: Even decaffeinated coffee contains a small amount of caffeine. Some individuals are highly sensitive and may still react to these trace amounts. Other factors like coffee’s acidity or additives can also be the cause.

Q: Should I stop drinking coffee if it makes me feel unwell?

A: Not necessarily. You might consider reducing your intake, switching to a less acidic brew like cold brew, or reducing additives. If symptoms persist or are severe, it’s best to consult a healthcare professional.

Q: Can sugar or cream in coffee cause negative feelings?

A: Yes, excessive sugar can lead to energy crashes and mood swings. Dairy or certain creamers can also cause digestive upset for individuals with lactose intolerance or sensitivities.

Q: What are withdrawal symptoms from coffee?

A: If you regularly consume caffeine and stop abruptly, you might experience headaches, fatigue, irritability, and difficulty concentrating. These symptoms are typically temporary.

What this page does NOT cover (and where to go next)

• Specific medical advice for diagnosed conditions like GERD or anxiety disorders. Consult a doctor for personalized treatment plans.
• Detailed comparisons of specific coffee bean origins, roast profiles, and their chemical compositions. Explore coffee enthusiast forums or specialized coffee blogs.
• The precise chemical breakdown of all compounds in coffee and their long-term health effects. Refer to scientific journals or health organizations for in-depth research.
• Recommendations for specific brands or types of coffee makers. Look for product reviews and guides focused on home brewing equipment.
• Advanced brewing techniques such as water chemistry optimization or specific extraction ratios. Seek out resources dedicated to specialty coffee brewing.