How Does Caffeine Affect The Human Body

Caffeine is the most abused drug in North America. 90% of adults consume some form of caffeine on a daily basis. Caffeine is natural, but it can also be man-made. It is safe for most healthy adults to consume up to 400 milligrams of caffeine a day. If you consume about the same amount of caffeine a day, your tolerance to the substance builds up. Caffeine can also mess with certain medications. You can expect to see withdrawal symptoms if stopped suddenly. There are also plenty of positive effects of caffeine as well. Caffeine has many effects on the systems of the human body: the nervous system, the digestive system, the respiratory system, the skeletal system, the muscular system, and the reproductive system. There are positive and negative

effects in regards to caffeine use.
There are many interesting facts about caffeine. Caffeine can stay in the body for hours, so even after the effects of this stimulate has wore off, it is still in the blood and tissues. It may take 8-12 hours to completely rid the body of the substance. Smoking and certain medications, including birth control, can make the caffeine stay in your body for a longer time period. People that regularly drink caffeine tend to wake up groggy, confused, or with a headache from the withdrawal symptoms of yesterday’s coffee.
The shape of caffeine is very similar to the neurotransmitter called adenosine. This substance binds to the same target, that is why it has so much effect on our bodies. Adenosine accumulates in the body during wakefulness and eventually causes us to become drowsy. When caffeine replaces this chemical it helps to keep our bodies alert and focused, instead of tired and groggy.
Cortisol is a natural chemical that helps keep you alert. The body is on a 24-hour biological schedule, known as the circadian clock. When first waking up, the brain is already flooded with cortisol, so even though you might feel you need a coffee, you do not really need one. It is best to wait until cortisol levels drop later in the day. 9:30-11:30 and 1:30-5:00 are the best times to have caffeine as the natural cortisol levels have depleted through the day.
Caffeine effects several different body systems.

The most prevalent impact would be on the central nervous system. The central nervous system contains the brain and the spinal cord. Caffeine reaches the brain quickly and acts as a stimulant. The most noticeable effect is alertness. Caffeine can cause headaches if consumed too much. On the other hand, if you normally consume caffeine and stop suddenly, this can lead to headaches as well. Caffeine is used in over-the-counter headache medicines to relieve some pain. When the body is not used to having caffeine in the system, it can give the jitters. If you have an anxiety disorder or a sleeping problem, caffeine may make it worse. The medical name for the jitters is chorea. Typical movements include bending or straightening the fingers, grimace in the face, or raising or lowering the shoulders. People with the jitters may look restless or anxious. It is also possible to overdose on caffeine. Symptoms of an overdose are confusion or hallucinations. This can lead to death from

convulsions.
Caffeine also has effects on the digestive and excretory systems. Caffeine raises the amount of stomach acid and may cause heartburn or upset stomach. It is also a diuretic, which means it helps your body remove water. Excess caffeine in your body does not get stored, it is processed through the liver and removed out of glands and urine. Large doses can cause you to lose too much water, especially in conjunction with exercise. Withdraws include nausea and vomiting, while overdose symptoms include diarrhea, excessive thirst, and increased urination.
The effects of caffeine on the circulatory and respiratory systems are rapid heartbeat, increased blood pressure, and breathing trouble. Caffeine is considered to be a vasodilator. This means that when caffeine is consumed, the blood vessels in the body widen, especially in the lungs and brain. This helps the body to breathe easier and reduce migraine pain. The extra increase in stress hormones can also increase blood pressure temporarily due to the changes in the blood vessels. When the body goes through withdrawal from caffeine the vessels in your brain and lungs constrict back down to normal. This can cause headache, upset stomach, and feel fatigued.
Large amounts of caffeine can affect absorption and metabolism of calcium. This contributes to thinning of bones also called osteoporosis. Withdrawal from caffeine can cause achy muscles, and symptoms of overdose would be twitchy muscles. Caffeine can also cause hard painful lumps on the breast. This is called fibrocystic disease. Caffeine can interfere with estrogen production production and metabolism, making it harder to get pregnant.
Caffeine intake should be limited during pregnancy.

According to the American College of Obstetricians and Gynecologists (ACOG), it is advised that pregnant women should not drink more than 200 milligrams per day, which is about an 11-ounce cup of coffee. When you drink a cup of coffee the caffeine from that crosses from the bloodstream to the placenta. The baby’s body takes a lot more time to metabolize the caffeine than the mother’s. As a result, the baby is exposed to the effects of caffeine than the mother. Researches continue to try to identify the exact relation to caffeine and pregnancy. ACOG also says that mild caffeine intake is not harmful to the fetus. One study found that if a mother consumed more than 300 milligrams of caffeine in a day the baby’s chances of being born small for their gestational age are greater. Also raising a pregnant woman’s heart rate and blood pressure puts unnecessary stress on the baby, which could be detrimental if the mother consumed enough caffeine. Some studies indicate that drinking too much caffeine can cause miscarriages. This has not been proven in many studies, however. Most women go off of the “better safe than sorry” method when dealing with caffeine during pregnancy. While caffeine will increase heart rate and blood pressure temporarily, caffeine is considered mostly safe during pregnancy in moderation. “In 2008, two studies on the effects of caffeine related to miscarriage showed significantly different outcomes. In one study

released by the American Journal of Obstetrics and Gynecology, it was found that women who consume 200mg or more of caffeine daily are twice as likely to have a miscarriage as those who do not consume any caffeine. In another study released by Epidemiology, there was no increased risk in women who drank a minimal amount of coffee daily (between 200-350mg per day.)
Due to conflicting conclusions from numerous studies, the March of Dimes states that until more conclusive studies are done, pregnant women should limit caffeine intake to less than 200 mg per day. This is equal to about one 12 oz cup of coffee” says americanpregnancy.org.
In young people, the effects can be seen with less caffeine the younger they are. It is not recommended that preschool aged children should consume more than 45 milligrams a day of caffeine. Too much caffeine in children can also be seen a lot quicker in hotter weather, this is because caffeine is a diuretic. Children are more susceptible to dehydration than adults. Caffeine can also stunt growth in children, a study examined the effects of low doses of caffeine in 52 children aged 8-9 and 49 children aged 15-17. In the younger kids, gender made no difference. But in the older group, the stimulant’s effects were felt more strongly by the boys. All in all, caffeine should be majorly limited in children and young adults because of all the negative effects it can have on them.
In Japan, researchers have shown that caffeine increases memory in adults. Also a newer study out of John Hopkins showed that a 2oo milligram caffeine tablet helped to increase memory consolidation. Michael Yassa, an assistant professor of psychological and brain sciences at Johns Hopkins, and his team of scientists found that caffeine has a positive effect on our long-term memory. Their research, published by the journal Nature Neuroscience, shows that caffeine enhances certain memories at least up to 24 hours after it is consumed. "We've always known that caffeine has cognitive-enhancing effects, but its particular effects on strengthening memories and making them resistant to forgetting has never been examined in detail in humans," said Yassa, senior author of the paper. "We report for the first time a specific effect of caffeine on reducing forgetting over 24 hours." The brain's ability to recognize the difference between two similar but not identical items, called pattern separation, reflects a deeper level of memory retention, the researchers said.
"If we used a standard recognition memory task without these tricky similar items, we would have found no effect of caffeine," Yassa said. "However, using these items requires the brain to make a more difficult discrimination—what we call pattern separation, which seems to be the process that is enhanced by caffeine in our case."
“Caffeine and carbohydrates are two of the most reliable performance-boosters out there. So what happens when you combine them? That's what researchers in Taiwan asked in a study just published in the European Journal of Applied Physiology -- and the results were surprising. They tested the effects of 6 mg per kilogram of body weight of caffeine taken one hour before exercise, and 0.8 g of carbohydrate per kilogram of body weight taken 10 minutes before exercise, using a repeated sprint protocol (10 sets of 5 short 4-second sprints on a stationary bike, with 20 seconds recovery between sprints and 2:00 between sets). Here is the peak performance they achieve in each set:”
(http://www.runnersworld.com/sweat-science/caffeine-and-carbs). “The caffeine results are harder to explain. The authors suggest that it may be a function of the specific protocol of sprints and recoveries, since improvements have been observed with longer sustained efforts as well as with longer recoveries between short sprints. They also found that caffeine seemed to raise cortisol levels when combined with carbohydrate, though those results are a bit hard to interpret. If I had to make a bet, I'd go with the ultra-short sprint protocol as the key variable that caused the lack of response” said Alex Hutchinson from the runnersworld.com.
Caffeine has major effects on all of the human body systems. The most major effect it has is on the central nervous system as it acts like a stimulant. This can stunt growth in children, make people nervous or anxious, and give people headaches. It is also possible to feel withdrawal symptoms and even overdose on caffeine. This is why it is so extremely important to be sure of the amount of caffeine that people are putting into their bloodstreams.