Caffeine TrackerCaffeine journalCAFFEINE JOURNAL
Understand every milligram you consume.
Evidence-based explanations of coffee and caffeine, from mechanisms to intake guidance. New articles are added regularly.
Coffee & nutrition
Does coffee block iron absorption? Timing meals and supplements
Learn how coffee polyphenols affect nonheme iron, who should care most and how to time meals or iron tablets without quitting coffee.
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Coffee & stomach
Is coffee on an empty stomach bad for you?
Learn what coffee does to acid, reflux and bowel motility, why it does not automatically cause gastritis, and how to test a gentler routine.
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Caffeine & exercise
Caffeine before exercise: dose, timing and performance
Learn where caffeine may improve endurance, strength and power, how much is commonly studied, when to take it and how to test your response.
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Caffeine & blood pressure
Does caffeine raise blood pressure? Short-term effects and long-term risk
Learn how caffeine can temporarily change blood pressure, what long-term studies show and how to measure your own response correctly.
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Food caffeine guide
How much caffeine is in chocolate? Dark, milk and cocoa compared
Compare caffeine in dark, milk and white chocolate and cocoa powder—and learn why cocoa percentage and serving size matter.
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Caffeine & headache
Can caffeine help a headache—or cause one?
Learn why caffeine can relieve some headaches, trigger others, and cause withdrawal pain when a regular dose is missed.
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Coffee timing
When is the best time to drink coffee after waking?
Does everyone need to wait 90 minutes? Learn what evidence says about morning alertness, dose and your last cup before sleep.
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Drink comparison
Coffee vs energy drinks: which has more caffeine?
Compare caffeine ranges, serving and container totals, natural versus added caffeine, and learn to read the label.
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Caffeine sensitivity
Why does coffee make me anxious, shaky or cause palpitations?
Understand caffeine jitters, anxiety, heart-rate effects, personal sensitivity and what to do when you feel unwell.
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Cold coffee guide
Cold brew vs iced coffee: caffeine, taste and brewing compared
Compare cold brew, iced coffee and iced Americano—and learn why ratio, dilution, size and shots determine caffeine.
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Pregnancy caffeine guide
Caffeine during pregnancy: is coffee safe and how much is too much?
Understand the 200 mg daily limit, count caffeine from every source and track coffee, tea, cola, chocolate and supplements.
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Caffeine comparison
Espresso vs coffee caffeine: which has more per shot, ounce and cup?
Compare concentration and total caffeine in espresso, filter coffee, Americanos and lattes—and learn why size and shots change the answer.
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Tolerance & tapering
Caffeine tolerance and withdrawal: why it feels weaker and how to cut back
Understand tolerance, the withdrawal timeline and a practical way to reduce caffeine gradually.
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Decaf guide
Is decaf coffee caffeine-free? Amounts, methods and how to choose
Learn how much caffeine remains in decaf, how it is removed and why serving size and preparation still matter.
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Hydration guide
Does caffeine dehydrate you? Coffee, water and the evidence
Caffeine can increase urine output, but ordinary coffee and tea still contribute fluid. Learn when hydration needs more attention.
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Drink comparison
Coffee vs tea vs matcha: which has more caffeine?
Compare typical caffeine amounts and learn why serving size, powder dose and brewing change the result.
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Sleep guide
How long does caffeine stay in your system? Half-life and sleep
Estimate what remains after each five-hour half-life and find a better cutoff for your last cup.
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Essential guide
What is caffeine? Effects, benefits, risks and amounts in common foods
Learn how caffeine promotes alertness, its benefits and side effects, and approximate amounts in common foods and drinks.
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