Welcome to Cool Stuff. My name's Marcus Paff, Reggie Rizzou, alongside today as well. Coming up, caffeine.

So many of us rely on it to wake up and stay alert each day. But what's the appropriate amount?

Modern energy drinks complicate that matter, but science does have some answers to help you better

understand your approach to consumption. Plus, Earth's seasons are increasingly out of sync.

What's driving this phenomenon and what does it mean for we humans? That plus a look at this day

in history coming up. It's cool stuff. The story comes to us from BBC Science Focus and author Andy Ridgeway.

Caffeine has been getting a bad rap recently, whether it's highly caffeinated energy drinks

making it difficult for kids to concentrate in class, or too many teas and coffees during

the day leaving us unable to sleep at night, caffeine in many people's

eyes is a cause for alarm. As such, the general advice regarding caffeine consumption increasingly

seems to be cut back on it or cut it out altogether. But it's not as if caffeine is entirely

without merit. There's no denying it's a psychoactive substance, or to put it more

bluntly, caffeine is a drug, the world's most widely consumed drug for that matter. In fact,

chances are you're under its influence right now. But like many drugs in the right dose, it has

benefits. It was the clarity and energy that doses of caffeine provided, distributed via the tea and coffee houses of Europe, that helped usher in the Enlightenment and make the switch from farms to factories during the Industrial Revolution.

But dosage is the key variable.

And although coffee and tea have been providing us with a tasty pick-me-up for centuries. Nowadays, more of us are consuming

caffeine in much higher concentrations due to the boom in energy drinks and tablets. This has prompted

a rise in research into caffeine, as scientists work to better understand its effects on us

and the mechanisms by which it produces them. So what are we learning from all this research?

Well, for one thing, just how differently each of us processes and reacts to caffeine.

But perhaps more importantly, it's providing evidence that as well as perking us up in the morning,

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