Coffee was mainly used only in the Arab world until the 15th century. The country where the coffee beans were first used is Ethiopia (meant to keep people awake during praying).
In the 16th century, cafes appeared in Istanbul, Cairo and Mecca, and in 1573 coffee arrived in Europe. The tea was introduced later in 1657, but quickly became very popular (Lao Zi, the founder of Daoism recommends tea as an elixir for his disciples).
Caffeine, the most commonly used stimulant, is found primarily in coffee tree seeds (Coffea Arabica), but tea leaves (Thea sinensis) and cocoa seeds (Theobroma cacao) are also sources of caffeine. Caffeine is also reported in drug trafficking as a counterfeiter used to mimic the stimulant action of amphetamis. The most important types of coffee are Arabica and Robusta.
Arabic coffee is the most consumed coffee.
Caffeine content expressed on a dry weight basis varies between 0.9-2% in Arabica green coffee seeds and 1.3% in fried Arabica coffee seeds. Robusta coffee is mainly consumed in France, Italy, UK.
The average caffeine content is nearly 2 times higher and is between 1.6 to 2.4% of the dry weight for the green seeds.
Caffein is a bitter substance, an alkaloid that is part of the family of heterocyclic compounds, also know as purines, and a member of a naturally occurring group of substances called methylxanthines.
The chemical formula of caffeine is C8H10N402. It has a molecular mass of 194.19 grams, is water soluble and soluble in many other organic solvents and has a melting point of 238 degrees Celsius. In pure form, caffeine appears as white crystals and can be prepared by extraction from natural sources.
How does it work?
While neurons “burn” throughout the day, a neurochemical substance called adenosine raises its levels in your body. The nervous system uses receptors specifically to monitor your body’s adenosine levels. As the day passes, more adenosis passes through those receptors and makes you feel sleepy.
That is why we get tired when night comes. Adenosine is a chemical present in all human cells, that functions in the brain as a inhibitory neurotransmitter. This means that adenosine can act as a central nervous system depressor.
Under normal conditions, adenosine causes sleep and suppresses emotion by slowing down nerve activity.
For a nervous cell, caffeine looks exactly like adenosine, but causes its inverse effect, so the body will cease to function properly, and instead of resting, the cells will “reactivate”.
At the same time, caffeine stimulates, through complex processes, the adrenal glands, which release adrenaline and norepinephrine in the body – neurotransmitters that also increase altertness and provide extra energy.
How does it help in body
There is a reason why you will find caffeine in most commercial fat burning supplements. Caffeine is one of the few natural substances that has been proven to actually help burn fat. Several studies show that caffeine can stimulate the metabolic rate by 3-11%.
Beneficial effects of coffee on sports activity have been discovered in studies which have shown that caffeine can increase fat burning by 10% in obese people and 29% in thin people.
Caffeine, partly due to its stimulating effect on the central nervous system increases both metabolism and oxidation of fatty acids.
Caffeine also increases the levels of epinephrine in the blood. This is the so-called “fight or run” hormone, designed to make our bodies ready for physical exercise.
Caffeine improves athletic performance by mobilizing fatty acids from adipose tissues. In two separate meta-analyzes, it was found that caffeine increases exercise performance on average by 11-12%.
The liver is a remarkable organ that performs hundreds of vital functions in the body. The liver is very vulnerable to modern day substances such as alcohol and fructose. Cirrhosis is the end stage of hepatic damage, caused by diseases such as alcoholism and hepatitis. In cirrhosis, liver tissues has been extensively replaced by scar tissue. Several studies have shown that coffee can reduce the risk of cirrhosis by more than 80% with the largest effect being in those who drink 2 to 3 cups of coffee perday.
Many people still seem to believe that coffee is unhealthy. This is not surprising though, it is very common for conventional wisdom (universally accepted knowledge) to be in contradiction with what studies say. In two very large epidemiological studies, coffee consumption was associated with a lower risk of death in all cases. This effect is particularly profound for type II diabetics. A study showed that coffee drinkers had a 30% lower risk of death over a 20 year period.
Coffee beans are filled with nutrients which make coffee a drink that actually contains a decent number of vitamins and minerals. A cup of coffee contains: 6% pantothenic acid (vitamin B5), 11% riboflavin (vitamin B2), 2% niacin (B3) and thiamine (B1), 3% manganese. It does not seem much, but it helps. Coffee also contains antioxidants.
Type II diabetes is a life-threatening illness that has reached epidemic proportions and has increased 10 times in the last decades, now affecting about 300 million people. This disease is characterized by a high level of glucose in the blood, as a result of insulin resistance or insulin deficiency. In observation studies, coffee has been consistently associated with a lower risk of diabetes. Risk reduction ranges from 23% to 68%. A massive review article examined 18 studies with a total of 457,922 participants. Each cup of coffee a day reduced the risk of diabetes by 7%, but that does need you should exceed the daily limit.
Coffee not only makes you smarter for a certain amount of time, it can also protect your brain from the effects of old age. Alzheimer’s is the most common neurodegenerative condition in the world and one of the main causes of dementia. In prospective studies, coffee users showed a 60% lower risk of Alzheimer’s and dementia. Parkinson’s is the second most widespread neurodegenerative disorder, characterized by the death of dopamine producing neurons in the brain. Coffee may reduce the risk of Parkinson’s by 32-60%
Depression is a serious mental disorder, which is the cause of a significant reduction in quality of life. Today, up to 20% show symptoms of depression, 10 times more than in 1945. In a Harvard study published in 2011, it is claimed that women who drink 3 cups of coffee a day have a 20% lower risk of becoming depressed. Another study involving 208,424 people found that those who drank 4 or more cups of coffee a day were 53% less prone to suicide.
This is what happens in your body after a cup of coffee:
Brain: you feel awake and alert. Caffeine binds to receptors in the brain, blocking adenosine’s sleepiness effect and accelerating neuronal activity. Coffee can also potentiate the effect of migraine analgesics. Caffeine helps absorption and can lead to blood vessel constriction.
Blood pressure: by blocking adenosine, caffeine can prevent the widening of arteries, the result is a temporary increase of blood pressure
Metabolism: caffeine restricts the activity of an enzyme that stops heat production. As a result, your body will produce more heat, which will help you burn more calories
Colon: caffeine stimulates intestinal transit and helps you go to the toilet. It releases bile acids in the intestine, producing a laxative effect, as well as the urgent need to use the toilet.
How many maximum cups one can consume in a day
95 mg is the amout of caffeine equivalent to 230 ml of coffee (A cup of coffee is between 230 and 350 ml.)
300 mg (about 700 ml of coffee) the average amount consumed daily by an adult on a worldwide scale
400 mg (about 940 ml of coffee) this is the daily amount of caffeine consumption threshold you should not exceed
500 to 600 mg (1.2 to 1.4 liters) this is a strong dose that can cause tachycardia, insomnia or tremor
5 to 50 grams (11.8 to 118 liters) this is the amount of caffeine that can kill you. Such cases are rare.
How long does caffeine stay in your system
Caffeine is easily absorbed in the body, the blood level reaching the maximum value at approx. 30 minutes after ingestion. The rate of caffeine removal from the blood varies from a few hours in an adult to a few days in the newborn. The rate of elimination is reduced during pregnancy and by the use of oral contraceptives.
Smoking, on the other hand, seems to increase the caffeine elimination rate in the body. For this reason, caffeine intake should be greatly reduced or eliminated by persons trying to quit smoking, to prevent increased caffeine levels in blood and the possible increased craving for nicotine. Dependence, evidenced by the symptoms can only be instituted after 6-15 days of exposure to 600mg or more caffeine daily.