Coffee, the confusing benefits

Coffee to me is an drink which I probably use to wake myself in the mornings, more or less its function as a stimulate has helped millions of workers to keep going. even with hidden benefits such as a reduction in the probability to have type two diabetes, Parkinson's disease and dementia.
A May 2012 study by the New England Journal of Medicine found that, during the course of their study, coffee drinkers "who drank at least two or three cups a day were about 10 percent or 15 percent less likely to die for any reason during the 13 years of the study." The researchers who conducted the study said that this doesn't necessarily provide a cause-and-effect relationship, but will help point other researchers in the right direction.

Several studies comparing moderate coffee drinkers (defined as 3–5 cups per day) with light coffee drinkers (defined as 0–2 cups per day) found that those who drank more coffee were significantly less likely to develop Alzheimer's disease later in life. A longitudinal study in 2009 found that moderate coffee drinkers had reduced risk of developing dementia in addition to Alzheimer's disease.

Many people drink coffee for its ability to increase short term recall. Likewise, in tests of simple reaction time, choice reaction time, incidental verbal memory, and visuospatial reasoning, participants who regularly drank coffee were found to perform better on all tests, with a positive relationship between test scores and the amount of coffee regularly drunk. Elderly participants were found to have the largest effect associated with regular coffee drinking. Another study found that women over the age of 80 performed significantly better on cognitive tests if they had regularly drunk coffee over their lifetimes.
Coffee can also reduce the incidence of cirrhosis of the liver and has been linked to a reduced risk of hepatocellular carcinoma, a primary liver cancer that usually arises in patients with preexisting cirrhosis.

Coffee consumption is also correlated in Africa to a reduced risk of oral, esophageal, and pharyngeal cancer. In the Nurses' Health Study, a modest reduction in breast cancer was observed in postmenopausal women only, which was not confirmed in decaffeinated coffee, and a reduction in endometrial cancer was observed in people who drank either caffeinated or decaffeinated coffee. According to one study, coffee protects the liver from cancer. Another preliminary study found a correlation between coffee consumption and a lower risk of aggressive prostate cancer.

A 2009 prospective study in Japan following nearly 77,000 individuals aged 40 to 79 found that coffee consumption, along with caffeine intake, was associated with a reduced risk of dying from cardiovascular disease.
Coffee is also a powerful stimulant for peristalsis and is sometimes considered to prevent constipation. However, coffee can also cause excessively loose bowel movements. The stimulative effect of coffee consumption on the colon is found in both caffeinated and decaffeinated coffee.Contrary to popular belief, caffeine does not act as a diuretic when consumed in moderation (less than five cups a day or 500 to 600 milligrams), and does not lead to dehydration or to a water-electrolyte imbalance; current evidence suggests that caffeinated beverages contribute to the body's daily fluid requirements no differently from pure water.

John Hopkins researchers found that caffeine-related performance improvement is nonexistent without caffeine withdrawal. In essence, coming off caffeine reduces your cognitive performance and has a negative impact on your mood. The only way to get back to normal is to drink caffeine, and when you do drink it, you feel like it’s taking you to new heights. In reality, the caffeine is just taking your performance back to normal for a short period.

Drinking caffeine triggers the release of adrenaline. Adrenaline is the source of the “fight or flight” response, a survival mechanism that forces you to stand up and fight or run for the hills when faced with a threat. The fight-or-flight mechanism sidesteps rational thinking in favor of a faster response. This is great when a bear is chasing you, but not so great when you’re responding to a curt email. When caffeine puts your brain and body into this hyper-aroused state, your emotions overrun your behavior. Irritability and anxiety are the most commonly seen emotional effects of caffeine, but caffeine enables all of your emotions to take charge.

The negative effects of a caffeine-generated adrenaline surge are not just behavioral. Researchers at Carnegie Mellon University found that large doses of caffeine raise blood pressure, stimulate the heart, and produce rapid shallow breathing, which readers of Emotional Intelligence 2.0 know deprives the brain of the oxygen needed to keep your thinking calm and rational.

When you sleep, your brain literally recharges, shuffling through the day’s memories and storing or discarding them (which causes dreams), so that you wake up alert and clear-headed. Your self-control, attention, and memory are all reduced when you don’t get enough—or the right kind—of sleep. Your brain is very fickle when it comes to sleep. For you to wake up feeling rested, your brain needs to move through an elaborate series of cycles.

You can help this process along and improve the quality of your sleep by reducing your caffeine intake. Here’s why you’ll want to: caffeine has a six-hour half-life, which means it takes a full twenty-four hours to work its way out of your system. Have a cup of joe at eight a.m., and you’ll still have 25% of the caffeine in your body at eight p.m. Anything you drink after noon will still be at 50% strength at bedtime. Any caffeine in your bloodstream—with the negative effects increasing with the dose—makes it harder to fall asleep.

When you do finally fall asleep, the worst is yet to come. Caffeine disrupts the quality of your sleep by reducing rapid eye movement (REM) sleep, the deep sleep when your body recuperates and processes emotions. When caffeine disrupts your sleep, you wake up the next day with an emotional handicap. You’re naturally going to be inclined to grab a cup of coffee or an energy drink to try to make yourself feel better. The caffeine produces surges of adrenaline, which further your emotional handicap. Caffeine and lack of sleep leave you feeling tired in the afternoon, so you drink more caffeine, which leaves even more of it in your bloodstream at bedtime. Caffeine very quickly creates a vicious cycle.

Like any stimulant, caffeine is physiologically and psychologically addictive. If you do choose to lower your caffeine intake, you should do so slowly under the guidance of a qualified medical professional. The researchers at Johns Hopkins found that caffeine withdrawal causes headache, fatigue, sleepiness, and difficulty concentrating. Some people report feeling flu-like symptoms, depression, and anxiety after reducing intake by as little as one cup a day. Slowly tapering your caffeine dosage each day can greatly reduce these withdrawal symptoms. As with anything coffee should be taken with in moderation, the general census is to take up to 3 cups on average a day to gain health benefits. Though to avoid a sleepless night your last cup should be 6 hours before you sleep.