Thread: Is Coffee Unhealthy?

Read this >> http://www.consumerreports.org/main/...=1025209657511

May be this will make someone feel better...=)

Beneficial Effects
Scientific evidence continues to show that not only is coffee drinking in moderation perfectly safe, and no threat to health, it can also have some health benefits.

COFFEE AND BRONCHIAL ASTHMA

Caffeine has long been known to help asthmatics and many have found regular consumption of coffee to assist in moderating attacks. Scientifically this has been supported by two large studies in the USA and in Italy (1,2) where three or more cups of coffee per day were associated in a dose related manner with reduced prevalence of asthma.

Further evidence of improved ventilatory function was shown in exercise-induced bronchoconstriction (3) but required approximately six cups of coffee. In this context the authors found no problem with tolerance of this dosage.

Chest physicians advise withdrawal of caffeine from the diet for at least four hours preceding bronchial challenge testing (4).

Overall, there appears to be support for the view that coffee drinking helps asthma sufferers, though care should be taken that the daily intake of caffeine does not cause over-stimulation in susceptible individuals.

ANTIOXIDANT SUBSTANCES IN COFFEE

Caffeine is clearly a major biologically active substance in coffee and has received the most research attention. Coffee has a complex chemical composition, however, and the potential importance of many other constituents, albeit present in small concentrations, cannot be ignored. A characteristic of many plants is that they contain a diverse array of compounds with antioxidant properties and coffee is no exception. Polyphenolic compounds called flavonoids are particularly widespread in plants and important in disease protection (1). In addition to the compounds found naturally in raw beans, attention has also been given to changes occurring during roasting. Nicoli and colleagues (2) found evidence for substances with antioxidant activity to be generated during roasting probably as a result of the formation of Maillard complexes. Other authors isolated antioxidant activity due to maltol and 5-hydroxymethylfurfural (3). This research is in its infancy but given the increasing interest in the beneficial role of food antioxidants in health, it seems likely that their role in coffee will become of increasingly more interest.

ALERTNESS AND MOOD

Caffeine can increase the speed of rapid information processing by 10% (1), and a cup of regular (caffeine containing) coffee after lunch helps to counteract the normal ‘post-lunch dip’ in ability to sustain concentration, aiding alertness (2). Research has also shown that a couple of cups of coffee help to improve alertness and concentration during night shift hours (3). These findings have been further endorsed by Smith et al (4) who conducted a study in 1993 to examine the effects of coffee on daytime and night-time performance and alertness. The results clearly demonstrated that caffeinated coffee had a beneficial effect on alertness and improved performance in a variety of tasks in both day and night sessions.

These effects are especially beneficial to night shift workers as it is known that many industrial accidents occur late into the shift when workers become less attentive. A further study by Smith et al (5) suggests that the alertness-enhancing effect of caffeinated coffee can remove the malaise (reduced alertness, slower psychomotor performance) associated with having the common cold, and that increased stimulation of the sensory afferent nerves may also be beneficial.

Countering Driver Sleepiness

Caffeinated coffee can also help prevent road accidents according to research undertaken at the Sleep Research Laboratory, University of Loughborough, UK. Two studies by J. Horne and and L. Reyner (6,7) concluded that counter measures to driver sleepiness should include a 30 minute break, 2 cups of coffee (about 250mg caffeine) and if feasible, a brief nap.

Reduced Depression and Anxiety

Additional studies found that caffeine helps to improve performance independently of its raising of fatigue-related concentration (1,8), and improves the performance of participants undergoing standard vigilance and reaction time tests (9), resulting in increased self-reported vigour, alertness and efficiency, and a decline in levels of depression and anxiety. Two prospective studies have found a clear significant inverse association between coffee drinking and risk of suicide (10,11). Whereas the researchers could not rule out a spurious effect that might have occurred if people at risk of depression had been advised to abstain from coffee drinking, they urged further research into the possibility that coffee drinking may decrease depression.

REDUCED RISK OF STONE FORMATION (CALCULI)

Patients with kidney stones are routinely advised to increase their fluid intake. The questions arise: is the type of beverage important and will the presence of caffeine, which may cause diuresis, pose a problem for such patients? In a prospective study of some 45,000 men with no history of kidney stones, Curhan et al (1) found that greater intakes of regular and decaffeinated coffee, tea, beer and wine were associated with a decreased risk of stone formation, whereas greater intakes of apple and grapefruit juices were related to increased risk. In a further study involving 81,000 women, by the same group of researchers (2) caffeinated coffee and wine were found to be significantly more effective than water in helping women avoid kidney stones. An 8-ounce serving of coffee offered a 10 percent lower risk, and decaffeinated coffee a 9 percent decrease.

Drinking coffee has also been associated with a lower risk of gallstone disease in men. In a 10-year prospective study, Leitzmann et al, (3) it was found that men who drank two to three cups of regular, caffeinated, coffee per day had a 40 percent lower risk of developing gallstone disease than men who did not drink regular coffee. This rose to a 45 percent lower risk for men who drank four or more cups of regular coffee per day. Coffee has several metabolic effects that could reduce the risk of gallstone formation and the researchers concluded that the effect may be due specifically to the effect of caffeine since other drinks with low or no caffeine content showed no significant association.

REDUCED RISK OF COLON CANCER

There is some convincing evidence for a protective effect of coffee against the development of colon or colorectal cancers (1-7). Such a protective effect was reported in a case-control study conducted in Sweden (6) with 352 cases of colon cancer, 217 cases of rectal cancer, and 512 controls. The authors concluded that "…coffee consumption appears to be protective against colon cancer, and tea against rectal tumors". A similar study in Italy found that the risk of colon cancer was reduced by drinking more than four cups of coffee a day and that this trend was dose-related (7). A mechanism for this protective effect has been suggested by Favero A. et al (8). Several studies have indicated that frequent eating may increase colon cancer risk and in this Italian study, Favero, A. et al, (8) set out to clarify this issue. The conclusion was that frequent eating increases, whereas high coffee intake decreases, the excretion of bile acids, which are suspected to be carcinogenic to the colon. Thus frequent coffee intake may counterbalance the effect of frequent eating.

FURTHER RESEARCH

Other compelling studies on positive health effects of coffee/caffeine range from its use:

as a topical treatment of atopic dermatitis
as a booster of pain-free walking for patients with chronic stable angina
as an early warning of the risk of falling into a diabetic coma in those dependent on insulin
in the prevention of postprandial hypotension in elderly patients
as a good dietary source of potassium