The truth about Caffeine
What’s the first thing you reach for in the morning? Your phone? Your partner? Chances are a cup of tea or coffee isn’t that far down the list. But why is that? The answer lies in the caffeine. It wakes you up and can enhance athletic performance, but it can also stop you sleeping; it’s addictive but legal.
Caffeine has been around a long time – Chinese literature dating as far back as 2700BC talks about its effects. Chemically, it is one of a group of compounds called xanthenes which are mild central nervous stimulants. It is found most commonly in coffee and tea, but also in many fizzy drinks, especially cola, as well as chocolate and many prescription and non-prescription medicines, such as pain killers and cold remedies. Once caffeine enters your blood it increases your heart rate, promotes secretion of stomach acid, speeds up urine production, dilates some blood vessels and constricts others. So is it good for us, or bad? What does it really do to our bodies and can it be useful in an exercise regime?
Exercise – performance enhancer
Research shows that a cup of coffee before you exercise can enhance performance because of caffeine’s stimulating effect on your heart and nervous system. It also helps release ‘feel good chemicals’ such as dopamine, meaning that you are more likely to enjoy getting hot and sweaty and pushing yourself, plus you can go that bit harder because your heart is pumping faster.
But, before you start necking the stuff, it’s worth noting that most people only need between 250mg to 300mg of caffeine per day to feel its enhancing effects and your average cup of coffee contains around 95mg caffeine. By comparison, a double espresso contains approximately 125mg of caffeine, although this varies from café to café, brand to brand – a Starbucks Tall brewed coffee, for example, has a whopping 260mg of caffeine, which is probably why you see so many people entering your gym with a Tall Starbucks in their hand!
With that mind, it might seem a good idea to consume more caffeine if you are trying to lose weight so that you can perform better in the gym, but this is not necessarily the case.
The effect of caffeine on spider web construction. Noever, R., J. Cronise, and R. A. Relwani. 1995.Using spider-web patterns to determine toxicity. NASA Tech Briefs 19(4)
Caffeine and weight loss/gain:
Caffeine may reduce, or even supress, your appetite and it has been reported to increase energy use. However, too much can cause nervousness, insomnia, nausea, increased blood pressure and other problems. It is also worth keeping in mind that some caffeinated drinks, such as specialty coffees, are high in calories and fat, which could lead to weight gain.
What’s more, because caffeine can have a direct impact on your stress levels (cortisol) and blood sugar balance, which in turn affects your weight balance, the combination of caffeine and cortisol makes it very difficult to lose weight.
Caffeine and sleep
One of the main reasons we all drink so much coffee or tea is to keep awake and alert, but did you know that caffeine can stay in your bloodstream for up to eight hours? It is no wonder some of us have difficulty come bedtime. If you are struggling to fall asleep, or find yourself waking up between 2-4am, typically referred to as broken sleep, this may well be because of the caffeine you have consumed during the day. This sleep deprivation is likely to make you more tired, leading to more caffeine the next day, starting a negative cycle effect.
Remember, caffeine is a stimulant – it wakes up the nervous system – which means it can also create a mild dependence. It is not addictive in the way that drugs and alcohol are but over consumption can lead to side effects if you decide to stop altogether. If you have been fairly dependent on caffeine and do decide to cut it out, you may want to be prepared for some of the following symptoms over the next few days:
- depressed mood
- difficulty concentrating
It’s not all bad
Most regular coffee drinkers will say that caffeine improves their alertness, concentration, energy and clear-headedness and there are scientific studies to support these subjective findings.
Other possible benefits include helping certain types of headache pain. Some people's asthma also appears to benefit from caffeine, due to its ability to increase airways, but while intriguing, these research findings are not proven and you should not adjust any medication without discussing it with your doctor.
Limited evidence suggests caffeine may also reduce the risk of the following:
- Parkinson's disease
- liver disease
- colorectal cancer
- Type 2 diabetes
The key – as with everything to do with your health and nutrition – is balance. A little caffeine may give you that vital boost to get you in the gym, but don’t overdo it.