Caffeine

Sources

Plants

Coffee

Yerba mate

Guarana

Kola nut

Cocoa

Tea

Other

Energy drinks/shots

Soda

OTC

oral (food, drink, pill)

How it Works

Blocks adenosine
(sedative neurotransmitter)

Helps dopamine (feel-good neurotransmitter) bind

Increases intracellular calcium

Uses/Effects

Mental alertness

Athletic performance

Headaches

Weight loss

Parkinson's

Breathing problems
(infants, asthma)

Stimulant

Regulation

Generally unregulated

Caffeinated alcohol banned

Can't sell bulk caffeine
to consumers

Must be listed on ingredient
list, but not amount

Concerns

Short-term

Overdose

Intoxication

Symptoms

Nervousness

Increased heart rate

Irritability

Insomnia

Doesn't cause lasting harm

Intakes of 1-1.5 g

Not very toxic

Dependence

Tolerance

Withdrawal symptoms
are short term

Not an addiction

Long-term

Minimal harmful effects
(up to 400 mg/day)

Specific populations

Pregnant women (<200mg)

Children (<100mg)

Patterns of use

Average intake 200 mg
(rec'd limit 400 mg)

Banned in some
religions