Posted by kathryn in Miscellanea

In my post about coffee yesterday I mentioned that a moderate amount of caffeine is considered okay – but what’s a moderate amount?

For an adult, this is generally considered to be between 300 and 400mg per day of caffeine, with over 600mg classed as excessive.

Four cups of espresso coffee gives about 360mg of caffeine, so falls within the bounds of moderate intake.

I know these are the generally recognised guidelines, but I still believe this is a lot of caffeine and too much for most people.

Caffeine is a central nervous system stimulant and it acts on the neurotransmitters in the brain. Caffeine inhibits the action of a neurotransmitter called adenosine, leading to increased dopamine activity. One of the many actions of dopamine is to stimulate the body’s sympathetic nervous system – the part that’s responsible for the stress, or fight-and-flight response. Dopamine increases your heart rate and blood pressure, while caffeine can also stimulate the release of adrenaline.

It strikes me that in our modern world most people’s lives are too full. Getting to and from work is stressful (certainly in Sydney) and people are working longer and longer hours. Do we really need to be drinking a lot of a liquid which perpetuates the stress response in our body? Surely we have too much stress already?

I’m not totally against coffee or even caffeine. I thoroughly enjoy a good cup of coffee each day and would not want to give it up. Having a coffee and reading the paper is part of my morning routine.

However, four cups does seem a lot to me and much more than a “moderate” amount. It certainly seems more than is healthy for most people. In my experience, most people need more ways of calming down and reducing their stress, than revving it up.

Photograph by Daniel Y Go under the terms of a creative commons license.

15 June, 2007