Caffeine in coffee:
8 ounces Brewed Coffee: 60-170mg, average around 115mg
8 ounces Instant Coffee: 40-120mg, average around 60-70mg
Espresso shot of coffee: around 80mg
What is caffeine?
Caffeine is a mild stimulant that is present in a variety of substances, including coffee, tea and chocolate. At low levels, it provides a gentle buzz and makes life more enjoyable. At too high, it makes you irritable, snarky and twitchy.
Is coffee good or bad for your health?
Within moderation, coffee is likely to be fairly safe. There is endless debate whether coffee is good for your health and not, but either way, for good or bad, the effect it has is likely to be slight.
It’s probably a good idea to restrict caffeine consumption to less than 400mg per day, or about 2-4 cups of coffee.
Remember, tea and other substances also contain caffeine.
Studies have shown that caffeine consumption increases energy levels as well as performance, although to a fairly small degree.
Does Coffee Stop Working?
It really depends on what you’re using it for. Heavy use of coffee to fight low levels of sleep is unlikely to work in the long run as you develop tolerance to that effect.
Additionally, coffee may have a strong initial effect on blood pressure and heart rate, while this tends to lessen with time.
It is possible that some of the effects of coffee actually become stronger with time.