Caffeine is drunk or eaten by everyone, but what is it actually? Is caffeine a drug? Why do people sleep less well after drinking a cup of coffee? How much caffeine can a person consume? What is the lethal dose? Can you consume caffeine while pregnant? Why do you shake after drinking coffee? You can read about caffeine and cancer, Parkinson’s and insulin in this article.
What is Caffeine?
Caffeine is a white, rather bitter substance. Caffeine is found in about 60 plants, such as guarana, cocoa and tea. Products containing caffeine are: coffee, cola, tea, chocolate and some painkillers to which caffeine has been added to counteract its sleep-inducing effect. Caffeine is one of the drugs, because caffeine affects alertness. Caffeine falls into the category of cocaine and taurine. Only caffeine has the effects to a much lesser extent than cocaine. According to certain sources, caffeine is the most commonly used (or misused) stimulant in sports. Endurance athletes use the substance to combat fatigue, sprinters to reduce reaction time and strength athletes to increase maximum strength.
How caffeine works:
Caffeine is quickly absorbed into the blood, almost 99% of the caffeine is already absorbed into the blood within 45 minutes after consumption. The effect is greatest between 15 and 120 minutes after drinking caffeine. Drinking coffee with milk and sugar slows down absorption. Caffeine stimulates many bodily functions. Caffeine acts directly on the brain and stimulates the release of the stress hormone adrenaline. This can make you feel more stressed, which can cause you to shake or get palpitations. The adrenaline also stimulates the release of dopamine. Dopamine is a neurotransmitter that stimulates your brain. You feel happier. So it has the same kind of effect as cocaine and heroin, but much milder.
Now we will take a closer look at the effects of caffeine. Caffeine is very similar to adenosine (a neurotransmitter). Adenosine binds to its own receptor to initiate further processes. Caffeine does not stimulate the adenosine receptor, but blocks it for adenosine. In the brain, adenosine causes slow brain activity. Because caffeine blocks the adenosine receptors, this effect is canceled. This also makes people feel less tired. Like the brain, the kidneys have many adenosine receptors. Caffeine blocks these receptors, causing more urine to be produced. Caffeine is broken down in the body by the liver. About half of the caffeine has disappeared from the body about four hours after consumption. Your body sees caffeine as a drug or toxin, so it wants to get rid of it as quickly as possible so that it does as little damage as possible. This defense of the body is provided by the liver. The liver produces enzymes that convert caffeine into a less harmful substance.
The Effects of Caffeine:
The effects of caffeine depend on a number of factors: age, drinking and smoking habits, physical condition and the breakdown rate of caffeine in the body. The effect is greatest about two and a half hours after drinking. The absorption is slowed down by adding milk and sugar to the coffee. The main effect of caffeine is a mild stimulant effect on the central nervous system. You can notice this: drowsiness decreases, feeling less tired and concentrating better. Caffeine has a stimulating effect on the brain, kidneys, stomach and intestines. When you consume too much caffeine, you can experience restlessness, shaking, dizziness, ringing ears, and heart palpitations. For some people this is already the case with 1 cup of coffee late in the evening. Others have no problem with it at all. Finally, caffeine ensures a faster excretion of moisture from the body. Caffeinated drinks cause the body to lose moisture more quickly through the urine than without caffeine. However, it is not the case that the body loses more water due to caffeine.
Parkinson’s and Caffeine
A study in Hawaii shows that the risk of Parkinson’s disease decreases as you consume more coffee per day. The trial was conducted on 8,000 Japanese men and found that men who drank no coffee at all were 5 times more likely to develop Parkinson’s than men who drank between 4 and 6 cups of coffee a day. It was about the caffeine in coffee because people who used products containing caffeine also had less chance of Parkinson’s. This disease is caused by the neurotransmitter dopamine. This is produced less so that muscles can no longer move properly and the hands will shake. Caffeine slightly increases the amount of dopamine in the brain.
Insulin and caffeine
Researchers from Nijmegen discovered through a study that the effect of insulin is influenced by caffeine. By often consuming a large dose of caffeine, the effect of insulin decreases. This effect is achieved with just four cups of coffee. Caffeine increased the levels of adrenaline in the body, while the amount of insulin also rises. This was because the receptors no longer worked properly under the influence of the large amount of adrenaline. The effectiveness of the receptors decreased by about fifteen percent. This is a problem in people who have an increased risk of Diabetes 2, adult-onset diabetes. In these people, too little insulin is made to remove the sugar from the blood. The receptors become less sensitive to insulin. The muscles therefore absorb less sugar, because the glucose is not converted into glycogen. The sugar accumulates in the blood and that is very harmful. If caffeine also affects the functioning of the receptors of insulin, the sugar concentration will only increase. An international study by KU shows that caffeine also has an effect on people with diabetes 1, where the pancreas can hardly make insulin. Because caffeine affects insulin, they have to inject more insulin in order to overtake blood sugar. If your muscles are not replenished quickly enough with glycogen, which can provide the energy during exercise, due to the inhibitory effect on insulin, the performance will be less the next day, because the muscles do not have enough energy.
Cancer and caffeine
A few years ago it was said that you could get cancer by drinking coffee. Many studies have consistently confirmed this, but the studies were all conducted on animals and could not be traced back to humans. But with the studies that have been done in recent years, that idea about coffee is being nullified. Apparently, various substances in the coffee even offer protection against cancer. For example, the chlorogenic acid in coffee appears to protect against colon and liver cancer. Substances in coffee have a similar effect as antioxidants, which stop cancer from developing in us.
Pregnancy and caffeine
The safe amount of caffeine for pregnant women is lower than average because the risk of miscarriage or a low birth weight baby increases when the mother takes in more caffeine. Furthermore, breastfeeding women should not drink too much coffee, tea and cola. If breastfed babies are restless, the amount of caffeine the mother takes in is the possible cause.
How Much Caffeine Is Too Much?
What is too much caffeine differs greatly from person to person, because not everyone is equally sensitive to the effect. Dutch men drink an average of almost 7 cups of coffee a day, while Dutch women drink 5 cups of coffee a day, and many people also drink tea and cola. Most people are not affected. The advice of the Nutrition Center is for people who are sensitive to caffeine, the advice is to use a maximum of 400 mg of caffeine per day. That’s about 5 cups of coffee a day. For women who are pregnant or breastfeeding, 300 mg applies. That’s about 4 cups of coffee.
Lethal dose
About 15 grams of caffeine is a lethal dose. This means that approximately 150 cups of coffee must be drunk within a few hours. That is so much coffee that it is likely that no one has died from an overdose of coffee. There have been cases of people dying from an overdose of caffeine pills.
The amount of caffeine in drinks
A 125 ml cup of regular Dutch coffee, brewed with a paper filter in a coffee maker, contains about 85 mg of caffeine. The caffeine content of a cup of coffee depends on the type of coffee, the strength of the coffee and the size of the cup or mug. A cup of tea of 125 ml contains approximately 45 mg and a glass of cola of 150 ml contains 5 to 35 mg. Cola contains approximately 30 mg caffeine per 150 ml glass. In terms of caffeine content, a cup of coffee corresponds to two cups of tea or more than two glasses of cola. Energy drinks with, for example, guarana can also contain a lot of caffeine.
If a drink contains more than 150 mg caffeine per liter, this must be indicated on the packaging from 2004 onwards.
