Question 1

How much caffeine is safe per day?

Accepted Answer

The FDA recommends that healthy adults consume no more than 400 mg of caffeine per day — roughly 4 cups of brewed coffee. Pregnant or breastfeeding women should limit intake to 200 mg, and adolescents to 100 mg. Children under 12 should avoid caffeine entirely.

Question 2

What is the half-life of caffeine?

Accepted Answer

Caffeine has an average half-life of about 5 hours in healthy adults, meaning half of the caffeine you consume is still in your body 5 hours later. Half-life varies from 3 to 7 hours based on genetics, pregnancy, smoking, and medications.

Question 3

How long before bed should I stop drinking caffeine?

Accepted Answer

Because caffeine has a 5-hour half-life, you should stop consuming it at least 8 hours before bedtime. For most people, that means no coffee or energy drinks after 2 PM if you go to bed at 10 PM.

Question 4

How much caffeine is in a cup of coffee?

Accepted Answer

An 8 oz cup of brewed coffee contains about 95 mg of caffeine. A single espresso shot has about 63 mg, and an instant coffee has about 62 mg. Decaf still contains about 2 mg per cup.

Question 5

How much caffeine is in an energy drink?

Accepted Answer

An 8.4 oz Red Bull has about 80 mg of caffeine. A 16 oz Monster or Rockstar has about 160 mg. High-performance energy drinks like Bang can contain up to 300 mg per 16 oz can.

Question 6

Can caffeine affect sleep?

Accepted Answer

Yes. Caffeine blocks adenosine receptors in the brain, which delays the onset of sleep and reduces deep sleep quality. To protect sleep, keep caffeine below 50 mg in the 8 hours before bedtime.

Caffeine FAQ

Caffeine FAQ

Caffeine FAQ

How much caffeine is safe per day?

What is the half-life of caffeine?

How long before bed should I stop drinking caffeine?

How much caffeine is in a cup of coffee?

How much caffeine is in an energy drink?

Does decaf coffee have caffeine?

Can caffeine affect sleep quality?

Is caffeine bad for you?

What are the symptoms of caffeine overdose?

How do I reduce caffeine without withdrawal headaches?

How does caffeine compare to other stimulants?

Does caffeine help with weight loss?