Is Caffeine good or bad for Health ?

Caffeine and Health
Caffeine is associated with several health conditions. People have different tolerances and responses to caffeine, partly due to genetic differences.

1. Sleep
Caffeine’s ability to help people stay awake is one of its most prized qualities. By contrast, too much caffeine can make it difficult to get enough restorative sleep.

Caffeine can block the effects of the hormone adenosine, which is responsible for deep sleep. Caffeine binds to adenosine receptors in the brain, which not only lowers adenosine levels but also increases or decreases other hormones that affect sleep, including dopamine, serotonin, norepinephrine, and GABA. 

Levels of melatonin, another hormone promoting sleep, can drop in the presence of caffeine as both are metabolized in the liver. 

Studies have found that higher caffeine intake appears to increase the amount of time it takes to fall asleep. It may also decrease total sleeping time, especially in the elderly. Caffeine remains in your system for an average of five hours, the time period may range from one and a half hours to nine hours, depending on the individual.

One study investigated how the timing of caffeine ingestion affects sleep. Researchers gave 12 healthy adults 400 mg of caffeine either six hours before bedtime, three hours before bedtime or immediately prior to bedtime. Both the time it took all three groups to fall asleep and the time they spent awake at night increased significantly.

These studies show that, if you like the taste of coffee, you must pay attention to both the amount and timing of caffeine intake to optimize your sleep.

2. Anxiety
In moderate doses, caffeine increases alertness. But, at higher doses, it leads to anxiety and nervousness, including people who are sensitive to caffeine.

Caffeine can increase anxiety at doses of 400mg or more a day. High amounts of caffeine may cause nervousness and speed up heart rate, symptoms that are also felt during an anxiety attack. Those who have an underlying anxiety or panic disorder are especially at risk of overstimulation when overloading on caffeine.

Caffeine triggers the release of adrenaline - a hormone associated with increased energy. At the same time, it blocks the effects of adenosine - a brain chemical, makes you feel tired.

3. Blood pressure
Caffeine stimulates the heart, increases blood flow, and increases blood pressure temporarily, particularly in people who do not usually consume caffeine. 

However, strong negative effects of caffeine on blood pressure have not been found in clinical trials, even in people with hypertension, and cohort studies have not found that coffee drinking is associated with a higher risk of hypertension. Studies also do not show an association of caffeine intake and atrial fibrillation (abnormal heart beat), heart disease, or stroke. 

Elevated blood pressure is a risk factor for heart attack and stroke because it may damage arteries over time, restricting the flow of blood to your heart and brain. Fortunately, caffeine’s effect on blood pressure seems to be temporary. Also, it seems to have the strongest impact on people who aren’t used to consuming it.

High caffeine intake has also been shown to raise blood pressure during exercise in healthy people, as well as in those with mildly elevated blood pressure. Therefore, paying attention to the dosage and timing of caffeine is important, especially if you already have high blood pressure.

4. Heart rate
The stimulant effects of high caffeine intake can make your heart beat faster. It may also lead to altered heartbeat rhythm, called atrial fibrillation, which has been reported in young people who consumed energy drinks containing extremely high doses of caffeine.

However, this effect doesn’t seem to occur in everyone. Indeed, even some people with heart problems may be able to tolerate large amounts of caffeine without any adverse effects. In one controlled study, when 51 heart failure patients consumed 100 mg of caffeine per hour for five hours, their heart rates and rhythms remained normal.

Regardless of the mixed study results, if you notice any changes in your heart rate or rhythm after drinking caffeinated beverages, consider decreasing your intake.

5. Weight
Caffeine is often added to weight loss supplements to help “burn calories.” There is no evidence that caffeine causes significant weight loss. It may help to boost energy if one is feeling fatigued from restricting caloric intake, and may reduce appetite temporarily. 

Caffeine stimulates the sympathetic nervous system, which plays a role in suppressing hunger, enhancing satiety, and increasing the breakdown of fat cells to be used for energy. 

Cohort studies following large groups of people suggest that a higher caffeine intake is associated with slightly lower rates of weight gain in the long term. However, a fairly large amount of caffeine (equivalent to 6 cups of coffee a day) may be needed to achieve a modest increase in calorie “burn.” Additional calories obtained from cream, milk, or sweetener added to a caffeinated beverage like coffee or tea can easily negate any calorie deficit caused by caffeine.

6. Digestive
In moderate amounts of coffee which can improve gut motility, prevent gastric reflux. But larger dose, coffee may make to loose stools or even diarrhea.

However, caffeine itself also seems to stimulate bowel movements by increasing peristalsis, the contractions that move food through digestive tract. Given this effect, it’s not surprising that large doses of caffeine may lead to loose stools or even diarrhea in some people.

7. Gallstones
Studies have shown that higher coffee consumption is associated with a lower risk of gallstones. Decaffeinated coffee does not show as strong a connection as caffeinated coffee. Therefore, it is likely that caffeine contributes significantly to this protective effect. 

The gallbladder is an organ that produces bile to help break down fats; consuming a very high fat diet requires more bile, which can strain the gallbladder and increase the risk of gallstones. It is believed that caffeine may help to stimulate contractions in the gallbladder and increase the secretion of cholecystokinin, a hormone that speeds the digestion of fats.

8. Liver
Most studies on liver disease and caffeine have specifically examined coffee intake. Caffeinated coffee intake is associated with a lower risk of liver cancer, fibrosis, and cirrhosis. Caffeine may prevent the fibrosis (scarring) of liver tissue by blocking adenosine, which is responsible for the production of collagen that is used to build scar tissue.

9. Muscle Breakdown
Rhabdomyolysis is a very serious condition in which damaged muscle fibers enter the bloodstream, leading to kidney failure and other problems.

Common causes of rhabdomyolysis include trauma, infection, drug abuse, muscle strain and bites from poisonous snakes or insects. In addition, there have been several reports of rhabdomyolysis related to excessive caffeine intake, although this is relatively rare.

In one case, a woman developed nausea, vomiting and dark urine after drinking 1liter of coffee containing roughly 565 mg of caffeine. Fortunately, she recovered after being treated with medication and fluids. That cause is a large dosage of caffeine to consume within a short period of time, especially for someone who isn’t used to it or is highly sensitive to its effects.

In order to reduce the risk of rhabdomyolysis, it’s best to limit your intake to about 250 mg of caffeine per day, unless you’re used to consuming more.

10. Parkinson’s disease
Caffeine may protect against Parkinson’s disease. Animal studies show a protective effect of caffeine from deterioration in the brain. Prospective cohort studies show a strong association of people with higher caffeine intakes and a lower risk of developing Parkinson’s disease. The caffeine in coffee has been found in animal and cell studies aim to protect dopamine-producing cells in the brain. Parkinson's disease (PD) is mainly caused by low dopamine levels. There is consistent evidence from epidemiological studies that high caffeine consumption is associated with a lower risk of this disease.

A systematic review of 26 studies, including cohorts and case-control studies, found a 25% lower risk of disease with high caffeine intake. It also showed a 24% lower in disease risk with every 300mg increase in caffeine intake.

A Finnish cohort study followed coffee consumption and PD development in 6,710 men and women for 22 years. At that time, after adjusting for known risks of PD, those who drank at least 10 cups of coffee per day had a significantly lower risk of developing the disease than those who did not.

A large group of men and women were followed for 10 and 16 years study of caffeine and coffee intake in Parkinson's disease. The results showed that men who drank a lot of caffeine, 6 or more cups of coffee per day (women who drank moderately 1 to 3 cups of coffee per day) had a 58% lower risk of developing this disease than those who did not drink coffee.

11. Asthma
Caffeine has a similar action to the medication theophylline, which is sometimes prescribed to treat asthma. They both relax the smooth muscles of the lungs and open up bronchial tubes, which can improve breathing. The optimal amount of caffeine needs more study, but the trials reviewed revealed that even a lower caffeine dose of 5 mg/kg of body weight showed benefit over a placebo. Caffeine has also been used to treat breathing difficulties in premature infants.

Note: this is research for teaching purposes, not advice for you. The use of caffeine dosage in medical treatment, it is necessary to consult a doctor.

12. Pregnancy and infertility
Caffeine can cross the placenta, and both mother and fetus metabolize caffeine slowly. A high intake of caffeine by the mother can lead to prolonged high caffeine blood levels in the fetus. Reduced blood flow and oxygen levels may result, increasing the risk of miscarriage and low birth weight. 

However, lower intakes of caffeine have not been found harmful during pregnancy when limiting intakes to no more than 200 mg a day. A review of controlled clinical studies found that caffeine intake, whether low, medium, or high doses, did not appear to increase the risk of infertility. 

13. Frequent Urination
Increased urination is a common side effect of high caffeine intake due to the compound’s stimulatory effects on the bladder.

Most research looking at the compound’s effects on urinary frequency has focused on older people and those with overactive bladders or incontinence.

One large study looked at the effects of high caffeine intake on incontinence in more than 65,000 women without incontinence. Those who consumed more than 450 mg daily had a significantly increased risk of incontinence, compared to those who consumed less than 150 mg per day.

If you drink a lot of caffeinated beverages and feel that your urination is more frequent or urgent than it should be, it may be a good idea to cut back on your intake to see if your symptoms improve.

Compiled and penned by Crocus Media