Have you ever had a day when coffee doesn't cut it? A US start-up has come up with a solution to boost your energy levels: a sprayable caffeine solution applied directly to the skin.
The thought of spraying caffeine directly on my skin like a perfume triggered alarm bells: I hate the shakes I get from drinking too much coffee, or the dull headache I get in the afternoon when I've overindulged. More than two cups a day and I crash.
But despite encouraging multiple doses a day, Sprayable Energy claims to give you eight times less than the amount of caffeine in one cup of coffee. It promises no instant buzz and no dreaded crash either - just alertness, more focus, and a steady increase of energy.
Research has shown that the cognitive benefits of caffeine plateau at far lower doses than are normally ingested when drinking coffee; less than 12.5mg had exactly the same effect on cognitive performance as 100mg (a standard cup of coffee).
Anything more does nothing to enhance your cognitive state or enable you to get more done in your day.
What's more, the more caffeine you have, the more you need. In brain chemistry, caffeine binds to the adenosine receptors in the brain. Usually, when adenosine binds to these receptors, it signals the body to start going into a rest state, but when caffeine binds, it blocks adenosine from binding, with the result that the body doesn't wind down: you stay awake and don't become drowsy and tired.