Coffee Dehydrates You
The most recent studies and literature reviews on the effects of caffeine during normal life activities conclude that moderate caffeine consumption does not lead to dehydration. During exercise, the best quality studies conclude that not only is moderate caffeine beneficial for endurance performance, it does not contribute to body dehydration. Coffee drinking in moderation contributes to our fluid intake and does not lead to significant loss of body fluid. So basically, since coffee is made from water, the intake of liquid is still greater than the liquid going out!

Coffee Sobers You Up
When consumed in moderation, caffeine has many positive effects, including increased mental and physical endurance and performance, as well as mental alertness. However, increased mental alertness does not mean that the effects of alcohol are reducedSo the answer is no, coffee doesn’t sober you up.

Coffee Stunts Your Growth
This is an old myth probably begun early in the last century when some coffee alternatives were alluding to such a possibility. But there is no evidence that coffee stunts growth.

Health Canada guidelines for Caffeine intake is:
Average adult – 400 mg/day (approx. 3 – 8oz cups)
Pregnant and breastfeeding women, and women trying to get pregnant – 300 mg/day (just over 2 – 8oz cups)

Espresso Has More Caffeine Than Regular Coffee
Contrary to popular belief, the amount of total caffeine in an espresso is less than a regular brewed cup of coffee because the usual serving size is much smaller (volume). So a typical serving of coffee would likely have about twice the caffeine of a typical serving of espresso.

Type of Drink Volume Caffeine (mg) Mean (range)
Filtered coffee 125 ml 85 (60-135)
Espresso 30 ml 60 (35-100)
Soluble instant coffee 125 ml 65 (35-105)
Decaffeinated coffee 215 ml 3 (1-5)