Caffeine occupies a strange niche within our nutritional habits.
It's the only psychoactive drug that stands to be almost entirely unregulated by authorities on a global level.
Marijuana and Benzedrine are both highly regulated, for instance, so it can seem strange that caffeine is handed out in almost dangerous levels.
On average, caffeine consumption on a global scale evens out at one cup of coffee per human, per day.
There's always a lot of controversy in the media over caffeine consumption, but there's also a lot of false information out there.
Here you'll find an unbiased look at the facts to help you make a better judgement on those morning cups of coffee, or energy drink before the gym.
As a rule, an adult shouldn't consume more than 250-300mg of caffeine a day.
Any more and it begins to build up in your system, leading to problems with sleep, body jitters, and diuretic properties (increased frequency of urination, and onset of diarrhoea).
Beyond that point the caffeine begins to reach toxic levels, and will eventually result in dependency, tolerance, and even death at lethal doses.
So, caffeine can be lethal, but you're unlikely to reach that level.
You'd need around 150-200mg of caffeine per kilo of body weight in your system at one time to die from an overdose.
In a 68 kilo man that'd come out at about a gram.
Most caffeine is flushed from your system entirely within six hours, so you'd need to drink a lot of energy drink in a short amount of time to reach that kind of level.
Over a number of months you could build up toxic levels of the drug by drinking more than your 300mg a day, but you'd notice a dependency well before it became dangerously toxic.
Let's look at coffee, energy drinks and soft drinks, then.
Energy drinks can have anywhere between 30-50mg of coffee per 100ml, so a 500ml can at 50mg/100ml will reach your daily levels immediately.
A 500ml bottle of soft drink is unlikely to be higher than 128ml, and two will reach your limit.
Coffee varies dramatically depending on whether it was dripped or brewed (dripped is about 50% higher), but you can expect it to range from as low as a soft drink to substantially more than an energy drink.
Caffeine dependency most commonly comes from drinking coffee excessively, two to three cups a day will take you comfortably over caffeine allowances.
Try and stay under these levels.
Withdrawal symptoms include insomnia, joint pain, headaches and an inability to concentrate.
These can last as long as 9 days, though are less likely to occur if you stay within recommended levels.