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Effect of Caffeine on Sleep

By: Wendy Jacob - Updated: 1 Aug 2013 | comments*Discuss
Coffee And Sleep Caffeinated Drinks

Coffee plays an important part in our lives. It helps wake us up in the morning, provides a pleasant end to a meal and generally plays a large role in society. Our high streets are now dominated by chains of coffee shops. It is readily available in most offices, bars, shops, stations, airports - in fact, there are very few places where coffee is not being served!

The stimulant in caffeine is also found in tea, chocolate, soft drinks and some nuts. Most of us are aware that caffeine is a stimulant, but it can be difficult to monitor how much is being consumed and how it affects the body.

Caffeine and Tea

Tea contains two alkaloids as well as caffeine. These are reputed to relax the smooth muscles of the body whereas coffee stimulates the heart and respiratory systems. This explains why tea is more soothing to drink and why many people turn to tea when they want to relax.

Stimulating Body and Mind

Caffeine affects the body in a number of ways;
  • Stimulates Central Nervous System, causing an increase in heart rate.
  • Increases Blood Pressure.
  • Decreases blood flow to skin and inner organs.
  • Increases Dopamine levels.
  • Releases free fatty acids from adipose (fatty) tissue.
  • Affects kidneys by increasing urination which can cause dehydration.

Caffeine Withdrawal

Coffee drinkers may experience symptoms such as headaches, fatigue, depression and mood changes in the first couple of days without coffee. These usually resolve naturally within 48 hours.

Caffeine and Health

Recent research has shown that coffee helps keep people consistently awake during extended periods. Regular low dose coffee intake may be particularly helpful for those involved in shift work or suffering from Circadian Rhythm disorders affecting sleep.

It has also been shown to help with cognitive functioning and reaction times. A combination of short naps and regular cups of coffee are recommended for shift workers, long distance drivers, and those suffering from jet lag.

Research has also looked into whether coffee taken at breakfast time has any affect on daytime alertness. Coffee taken early in the day is connected with improved alertness and a feeling of well being.

Coffee and Exercise

The physiological effects of caffeine on performance are impressive. Increased blood flow to the muscles and increased alertness help keep the body and mind active. A cup of coffee prior to exercise will increase stamina.

Coffee and Disease

Studies have shown that drinking coffee can contribute to a reduction in Type 2 Diabetes, reduce the chances of developing Cirrhosis of the Liver and have an affect on other diseases.

Coffee and Sleep

As the day ends our bodies go through a number of natural changes as we wind down preparing for sleep. The brain produces Melatonin which helps us relax and prepare for sleep, and the supply of Adrenalin, which keeps us alert during the day, decreases. These changes signal to the mind and body that it is time to calm down and go to sleep.

Caffeine suppresses Melatonin for up to 10 hours. It also promotes the supply of Adrenaline. This is the opposite of what we need to get a good night's sleep.

Coffee and caffeinated drinks should be avoided in the hours before bedtime. A cup of coffee in the morning, or regular low doses during the day may help keep you alert or even prove helpful if feeling drowsy but should be restricted to the earlier hours of the day.

The connection with coffee and exercise is impressive, but as exercise will also stimulate the body and nervous system both should be avoided in the hours before bed.

Studies have shown that coffee drinkers take twice as long to go to sleep than those drinking decaffeinate coffee. Coffee also stimulates the nervous system and too much coffee may cause 'jitters' and anxiety.

Anxiety is one of the main causes of Insomnia. Although life may be going smoothly, the physical feeling of feeling being 'on edge' and unable to sleep can make you anxious. This will also interfere with sleep.

Adapt Coffee Intake and Improve Sleep

There is no doubt that coffee is here to stay. It is an important part of our lives, keeping us alert, improving performance and a pleasant way to meet friends. It has also been shown to have an effect on a number of health problems and diseases.

The downside is that Coffee is a powerful stimulant. Taken excessively, or in the hours before bedtime it will interfere with your body and mind making it impossible to fall asleep. It is recommended that all stimulants including coffee and heavy exercise should be avoided at least 4 hours before bedtime.

Coffee has an important role in helping keep workers and travellers awake during times of sleep loss. This should be seen as a short term solution until normal sleep patterns can be resumed.

Coffee, Children and Sleep

Children are also drinking coffee at earlier ages and are consuming caffeine in soft drinks and other foods. The effect of caffeine on behaviour and sleep is an increasing problem. Parents are encouraged to restrict caffeine to avoid over stimulation and increase concentration and the ability to sleep.

Coffee shops have become important parts of our social life. In a 24 hour world coffee is available throughout the day and night. Its availability and the increased interest into this powerful 'bean', means that people are drinking increased amounts of coffee throughout the day and night. Used sensibly, coffee helps us get through the day but is best avoided in the hours before bedtime.

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I normally drink 2 mugs of coffee (which each mug is equal to 2 regular cups) in the morning of half and half. Half caffeinated and half decaffeinated coffee which I mix myself. Last night before going to bed I drank a cola beverage, that I felt contributed to a feeling tautness or tension in my muscles in the night. As I lay there, I thought I should cut back on the caffeinated portion of the coffee, and limit myself to 1 mug. I have high blood pressure which I have to take medication for. Maybe by reducing my intake of coffee this will take care of my blood pressure and my tension at night. Tension that I felt last night, I feel this morning had to been brought by the cola. For me, no more cola at night, relaxing tea instead.
TautinTucson - 16-Jan-12 @ 3:18 PM
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