Incredible Online Finds

Dr Farrimond said: ‘These times are about right: after drinking a caffeinated drink,  caffeine passes from the intestines into the blood and then into the brain and around the body.

‘It is a stimulant drug that works by clogging up the ‘tiredness signals’ in the brain. A chemical in the brain, called adenosine, plays an important role in how tired we feel – it tends to build up throughout the day, causing us to get sleepy in the evening. 

Caffeine is a crafty drug that temporarily blocks adenosine pathways, giving you a boost while allowing ‘feel good’ molecules in the brain (such as dopamine) to be released more readily. You feel more alert and you feel better about yourself!

30-50 minutes: After you finish your drink and your body has now fully absorbed the caffeine , your liver will often then react by absorbing more sugar. It’s during this time that your body has also absorbed most of the sugar initially in the drink as well.

By 50 minutes your body has fully absorbed the caffeine but your liver also starts taking in more sugar. When the one-hour mark hit you will experience a sugar crash

Dr Farrimond said: ‘Yes, ordinarily you would expect all the caffeine to be absorbed by about 45 minutes after drinking, although it could be longer if drunk as part of a meal. 

‘The liver breaks down caffeine and caffeine itself does indeed raise blood sugar levels. It’s not as straightforward as the infographic suggests, however. 

‘Caffeine can make low blood sugars worse in diabetics, for example. Interestingly, caffeine seems to be good for the liver and coffee consumption has been linked to lower rates of liver disease and liver cancer. The same hasn’t been shown for energy drinks, however.’

60 minutes: An hour in and you’ll likely be getting the dreaded ‘sugar crash’ , this often is a mix of the sugar levels in your bloodstream dropping as well as the effects of the caffeine dying down.

Dr Farrimond said: ‘Lots of scientists don’t think the ‘sugar crash’ actually exists. We think we know when our sugar levels are high or low, but we usually can’t. 

‘Eating a meal makes us feel tired for other reasons, and we do get a comedown from caffeine, which can start around this time. We can also feel a bit of a slump when the ‘happy hormones’ circulating in our brain start to wear off.’

In the next five to six hours your body reduces the content of caffeine in the bloodstream by half. 12 hours is the time it takes for all of the caffeine to be removed from the body

Five to six hours: Roughly five to six hours is the half-life of caffeine. This means that it takes this many hours for your body to reduce the caffeine content in your bloodstream by 50 per cent. For women who take an oral contraceptive this time is doubled.

Dr Farrimond said: This is accurate for normal weight adults. The oral contraceptive pill will make the half-life longer, although it may not be double as it depends on the precise tablet.

‘Pregnancy, liver damage and other drugs can also slow the rate at which caffeine is eliminated from the body. 

‘Importantly, children and teenagers have a significantly longer half-life, meaning caffeine will remain in their blood stream for longer and at higher levels than for adults. This is why caffeinated drinks can cause behavioral problems and anxiety issues in children.’

12 hours: 12 hours after finishing your energy drink for most people all the caffeine will have been removed from your bloodstream, the exact speed or time will vary from person to person.

Dr Farrimond said: ‘Yes, this is a fair approximation, excluding children and teenagers.

12 to 24 hours: For regular drinkers you’ll find that between 12 and 24 hours is the time for when you’ll start to feel withdrawal symptoms i.e. the urge for some caffeine, other affects of this include headaches, irritability and constipation.

Dr Farrimond said: ‘Caffeine withdrawal symptoms are usually overstated and aren’t as bad as with think they are. 

‘In blinded tests where coffee drinkers have their drinks changed for decaffeinated ones, the withdrawal effects are found to be pretty mild in most cases, if they exist at all.

Withdrawal symptoms can last for up to nine days and will depend on the amount of caffeine we drink. Everyone’s different, of course, but a lot of the ‘withdrawal’ symptoms seems to be in our mind.’

You will start to feel withdrawal symptoms including headaches, irritability and constipation between 12 to 24 hours. Your body needs seven to 12 days to become tolerant to caffeine and soon you will get used to it

Seven to 12 days: Dtudies have shown that this is the time frame that your body will become tolerant of your daily caffeine dosage, one study found those who took a caffeine pill while others had a placebo, showed identical moods, alert levels and energy after 18 days, those who had the high dosage of caffeine had got used to the caffeine fix.

Dr Farrimond said: ‘We do become tolerant of caffeine over time; needing more to get the same effect. it would be interesting to find out more about these ‘studies’. 

The graphic then goes on to explain why it might be good or bad to drink energy drinks

It states that most things in moderation and as part of a healthy balanced diet are fine and this goes for energy drinks. However, be careful though as there are often large amounts of sugar in many of the drinks.