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Science
Research-backed breakdowns of clinical studies, neurotransmitters, and how your brain actually works.
In the DECAF trial, AFib came back in 47% of daily coffee drinkers vs 64% of abstainers. What that and CRAVE mean, and what to ask your cardiologist.
Decaf matches regular coffee for liver, diabetes and mortality links, but not dementia. A study-by-study scorecard of which coffee benefits are caffeine.
Vyvanse and caffeine are both stimulants. What the FDA label says, what one study measured, which effects overlap, and what to ask your prescriber.
Yes, you can put creatine in coffee. Heat will not ruin it in the time it takes to drink a cup. What the caffeine studies found, and how to mix it.
150 mg of caffeine is a 16 oz Red Bull or a Tall Americano: fine for most adults, over a teen's daily limit. What it equals and how long it lasts.
100 mg of caffeine is about one 8 oz cup of coffee and a quarter of FDA's 400 mg a day. See what contains it, who it is a lot for, and how long it lasts.
Caffeine intolerance means a normal dose brings a racing heart, jitters, nausea or a lost night of sleep. Causes, how it differs from allergy, what to do.
Creatine is not a stimulant and no human trial shows it harming sleep. See what the studies found and why caffeine in the same scoop is the usual culprit.
The Stroop test times how fast you name an ink color while ignoring the word. See what it measures, how scoring works, and what a score can't tell you.
300 mg of caffeine is 75% of the FDA's 400 mg daily figure and the dose in one Bang, Reign or C4 Ultimate can. Who it is a lot for, and how long it lasts.
200 mg of caffeine is half the FDA's 400 mg daily figure and a full single dose for an adult. Who it is a lot for, what has it, and how long it lasts.
One table for 5K, 10K, half, marathon and ultra: mg per kg, when to take it, and where the late top-up goes. Built from the ISSN stand and 21 RCTs.
Caffeine can amplify normal hand tremor, mostly at 200 mg and up. Seven trials that measured surgeons' hands to the micron show which doses did what.
3 to 6 mg/kg about an hour before, then 100 to 200 mg late in a long ride. What three meta-analyses and a 15-rider top-up trial found, by ride length.
Ammonia is a one-minute reflex, pre-workout averages 254 mg of caffeine, and caffeine alone has the evidence. What each one does before a lift.
The NCAA flags caffeine at 15 mcg/mL in urine, about 500 mg taken 2 to 3 hours before a test. Here is the mg math, the WADA history, and what counts.
Smelling salts peak within 15 seconds and fade inside a minute, per Poison Control. What six lifting studies found and what the FDA warned, twice.
What is in Phil Mickelson's coffee, from his own words and the label, and why the caffeine plus L-theanine pairing is the part with real evidence.
One placebo-controlled trial gave 12 golfers caffeine at the first tee and the turn: 2.5 strokes better, less fatigue. The dose and the timing.
Sleep inertia is the fog after your alarm. A 2026 study of 2,355 adults found the average person needed 15.8 minutes to shake it.
Cortisol and adrenaline explain why do i feel better with less sleep. That alertness masks real impairment and fades within hours.
The second wind meaning in sleep science is the wake maintenance zone, a circadian alertness peak 2 to 3 hours before melatonin onset.
About 75 percent of adults with serious deficits never compensate on weekends. Find out whether you can make up sleep debt and what works.
A 2023 meta-analysis found caffeine cuts deep sleep by 11.4 minutes. A 2025 trial showed 100 mg placed 4 hours before bed still reduced it.