(Health) (Chem) Coffee: The Chemistry of Great Coffee
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#1: (Health) (Chem) Coffee: The Chemistry of Great Coffee Author: adediosLocation: Angel C. de Dios PostPosted: Tue Nov 08, 2005 3:29 pm

The Chemistry of Great Coffee
By Robin Lloyd
Special to LiveScience
posted: 08 November 2005
08:06 am ET

High-end coffee is suddenly seeping into fast-food restaurants faster than you can ask for fries with that.

McDonald's started offering organic coffee roasted by Green Mountain Coffee Roasters at 650 locations in New England and Albany, New York, this month. Burger King now lets you order coffee brewed one cup at a time, so you avoid that burnt taste.

The fast food chains are acknowledging America's love affair with quality java.

Coffee that's not rot gut is called specialty coffee in the industry, which means a higher grade of bean is used and the roasting and brewing is treated as a "craft."

In 2004, 16 percent of U.S. adults drank specialty coffee daily, according to the Specialty Coffee Association of America. This slice of the market, which involves cafes, kiosks, coffee carts and retail roasters, at a total of 17,400 locations, amounted to $8.96 billion by the end of 2003.

The United States imports and consumes more coffee than any other country.

How it's done

When it comes to great flavor, coffee chemistry boils down to roasting and brewing.

When the inside of the bean reaches about 400 degrees, it begins to turn brown. Oil locked inside the beans begins to emerge. This is when the flavor takes shape. The more oil, the stronger the flavor.

Roasted coffee is a perishable food. The flavor peaks a few days after roasting and fades once the coffee is exposed to air, light or moisture. For this reason, aficionados keep their beans or fresh grounds in an airtight container at room temperature.

If you're one of the many people who drink coffee for the pick-me-up, you might think an espresso or cappuccino would be most effective. Not necessarily so. Caffeine content goes up as the water spends more time in contact with the grounds. Espresso brewing takes 25 seconds. Other methods take several minutes. Darker roasts also yield more caffeine.

Flavor is the combination of aroma, acidity and body.

Body is the sensation of heft or viscosity, something like oil, on the palate. Longer roasting yields more body. But that also decreases acidity, the tingly taste on your tongue. So there's a trade-off between body and acidity.

Acidity isn't bitterness though. Bitterness comes from skimping on grounds when you brew, brewing for too long, and brewing in a pot or machine with residual grounds left from hours, days or weeks ago.

The Starbucks way

So you want to know how Starbucks does it?

First, they discard opened bags of beans after one week. Second, hot coffee is stored in thermal carafes, not on burners.

Third, they use two tablespoons of ground coffee for each six ounces of water. (The more standard recipe is one to two tablespoons per six ounces of water).

The company roasts at four plants, located in the U.S. and Amsterdam. Roasted coffees are immediately sealed in packages that let carbon dioxide gas out but keep air, light, water, and heat from getting in, Starbucks spokesman Chris Gimbl told LiveScience.

As Starbucks brews on, competition in the specialty coffee realm is expected to increase from outlets once known for the blandness of their coffee. Dunkin' Donuts, on to the idea and offering specialty brews for years, claims to have sold nearly a billion cups of coffee last year, more than any other retailer in the country.


Here are some sample questions and websites to explore further this topic:

Is Coffee good?



What are antioxidants?


How hot is 400 degrees Fahrenheit?


What is caffeine?


What are acidity, aroma and body?


How is coffee grown?




Last edited by adedios on Sat Jan 27, 2007 4:53 pm; edited 3 times in total

#2: Caffeinated Liver Defense Author: adediosLocation: Angel C. de Dios PostPosted: Sun Jan 22, 2006 8:31 am
Caffeinated Liver Defense
21 January 2006
Janet Raloff

What you drink may greatly affect your vulnerability to potentially life-threatening liver disease, a new study finds.

The liver, the body's largest solid organ, is a metabolic workhorse. It not only makes a host of proteins and blood-clotting factors, but also synthesizes and helps break down fats, secretes a substance that helps the body absorb fat and fat-soluble vitamins, and detoxifies many potential poisons.

Several circumstances can injure this vital organ, says James E. Everhart, an epidemiologist with the National Institute of Diabetes and Digestive and Kidney Diseases. Excessive alcohol consumption can do it. "Obesity, diabetes, and high iron levels [in blood] have also been associated with clinical liver disease," he adds.

All that's why this physician was pleasantly surprised by the results of his new study in the December 2005 Gastroenterology. It showed a protective effect from coffee and tea. People who routinely drank more than two cups of coffee or tea per day faced only half the risk of being hospitalized with cirrhosis and other types of serious liver disease as did people consuming less of these drinks. The data, collected as part of a federal survey of a cross-section of U.S. adults, spanned roughly 20 years and included 9,849 people.

Everhart points out that the benefits were limited to people at high risk of liver disease. However, with roughly one-third of U.S. adults obese and 7 percent battling diabetes, the at-risk population is anything but small.

Is it the caffeine?
Everhart and Constance E. Ruhl of a Washington, D.C.–area public health–consulting company, analyzed reported consumption patterns of coffee, tea, and other caffeinated substances—such as certain soft drinks and chocolate—for people who participated in the first National Health and Nutrition Examination Survey (NHANES-I). For this decades-long project, federally funded researchers assessed the health of people when they were first recruited, between 1971 and 1975, and again on four separate occasions into the early 1990s.

The researchers identified people who had been hospitalized for or died from liver disease during the follow-up period and compared their earlier reported consumption of caffeinated beverages with that of people who hadn't had liver disease serious enough for hospitalization. The comparison revealed no effect from caffeine. However, the researchers then restricted their analysis to people at high risk of liver disease, such as those who were seriously overweight or had diabetes, were over 40, or reported downing at least one alcoholic drink per day.

Among these people overall, the risk of death or hospitalization from liver disease during the 20-year follow-up was 1.4 percent. However, among people who drank less than a cup of coffee or tea per day, the risk was 1.8 percent, and among study participants drinking one to two cups per day, the risk was 1.6 percent. Among people drinking even more of the beverages, the risk of serious liver disease was just 1.1 percent.

No effect on liver disease emerged among people drinking only decaf coffee, instant coffee, herbal teas, or cola. Data on these sources became available only in an early-1980s follow-up survey of the participants. However, when caffeine from all sources—including colas and chocolate—was summed, a related pattern took shape: Risk of liver disease dropped as total caffeine consumption climbed. Everhart notes that coffee consumption dominated these caffeine-consumption totals.

Explains Everhart, the focus was on caffeine "because it's the most well-known, metabolically active compound in coffees and teas. But it's unclear that the new finding is due exclusively to caffeine—or even caffeine at all." It's possible, he says, that protection is being conferred by one or more other compounds present in these drinks.

Why look in the first place?
Over the past decade, a handful of studies have reported that among certain subsets of liver-disease patients—chiefly those with cirrhosis—heavy coffee consumption appeared protective. A host of additional studies found that abnormal liver-enzyme concentrations, usually indicative of liver disease, were more likely to show up in people who drank the least coffee.

Clearly, the studies suggested some type of liver protection by caffeine or coffee, Everhart says.

In an earlier test of this apparent trend, Ruhl and Everhart examined caffeine consumption and the results of blood tests in 6,000 adults who participated in the NHANES-III study, conducted between 1988 and 1994. They found that among people at high risk of liver disease, "consumption of coffee and especially caffeine" was linked to reduced risk of abnormal liver-enzyme activity. The researchers reported their findings in the January 2005 Gastroenterology and then moved on to the current study.

"I keep bugging my colleagues that they need to study this [coffee-tea-liver association] in a more rigorous way to find the potential mechanism of action for caffeine or other compounds in these beverages," Everhart says. Indeed, he notes, with more than a decade of increasingly stronger hints that caffeinated beverages are beneficial, "we still have nothing but speculation about why they might be protective."


Ruhl, C.E., and J.E. Everhart. 2005. Coffee and tea consumption are associated with a lower incidence of chronic liver disease in the United States. Gastroenterology 129(December):1928-1936. Abstract available at http://www.gastrojournal.org/a.....9/abstract or http://dx.doi.org/10.1053/j.gastro.2005.08.056.

______. 2005. Coffee and caffeine consumption reduce the risk of elevated serum alanine aminotransferase activity in the United States. Gastroenterology 128(January):24-32. Abstract available at http://dx.doi.org/10.1053/j.gastro.2004.09.075 or http://www.gastrojournal.org/a...../abstract.

Further Readings:

Fackelmann, K. 1997. Rusty organs. Science News 151( Jan. 18 ):46-47. Available at http://www.sciencenews.org/pag.....7/bob1.htm

Raloff, J. 2004. Got diabetes? Try ditching caffeine. Science News Online (Aug. 7). Available at http://www.sciencenews.org/art.....7/food.asp

______. 2004. Diabetes: Coffee and caffeine appear protective. Science News Online (Jan. 17). Available at http://www.sciencenews.org/art.....7/food.asp

______. 2000. Chocolate therapies (with recipe for Janet's chocolate medicinal mousse pie). Science News Online ( March 18 ). Available at http://www.sciencenews.org/art.....8/food.asp

______. 2001. Decaf may not always be best. Science News Online (Nov. 24). Available at http://www.sciencenews.org/art.....4/food.asp

______. 1996. Addicted to java? Don't press it! Science News Online (Nov. 30). Available at http://www.sciencenews.org/pag.....6/food.htm

______. 1995. New support for tea's heart-y benefits. Science News 148(Dec. 9):399.

______. 1995. Coffee: Brewing's link to cholesterol. Science News 148(Sept. 16):182.

______. 1995. Filtered coffee friendlier to the heart. Science News 147(Feb. 4):72.


James E. Everhart
Epidemiology and Clinical Trials Branch
Division of Digestive Diseases and Nutrition
National Institute of Diabetes and Digestive and Kidney Diseases
2 Democracy Plaza, Room 655
6707 Democracy Boulevard, MSC 5450
Bethesda, MD 20892

Constance E. Ruhl
Social and Scientific Systems, Inc.
8757 Georgia Avenue, 12th Floor
Silver Spring, MD 20910

Last edited by adedios on Tue Mar 21, 2006 7:53 am; edited 1 time in total

#3: Coffee consumption linked to increased risk of heart attack Author: adediosLocation: Angel C. de Dios PostPosted: Wed Mar 08, 2006 7:55 am
JAMA and Archives Journals
8 March 2006

Coffee consumption linked to increased risk of heart attack for persons with certain gene variation

Individuals who have a genetic variation associated with slower caffeine metabolism appear to have an increased risk of non-fatal heart attack associated with higher amounts of coffee intake, according to a study in the March 8 issue of JAMA.
Studies examining the association between coffee consumption and risk of myocardial infarction (MI – heart attack) have been inconclusive. Coffee is a major source of caffeine, which is the most widely consumed stimulant in the world and has been implicated in the development of cardiovascular diseases such as heart attack, according to background information in the article. However, coffee contains a number of other chemicals that have variable effects on the cardiovascular system. It is not clear whether caffeine alone affects the risk of heart attack or whether other chemicals found in coffee may be responsible. Caffeine is metabolized primarily by the enzyme cytochrome P450 1A2 (CYP1A2) in the liver. Variations of the gene for this enzyme can slow or quicken caffeine metabolism. Carriers of the gene variant CYP1A2*1F allele are "slow" caffeine metabolizers, while individuals with the gene variant CYP1A2*1A allele are "rapid" caffeine metabolizers.

Ahmed El-Sohemy, Ph.D., of the University of Toronto, and colleagues conducted a study to determine whether gene variations of CYP1A2 modifies the association between consumption of caffeinated coffee and risk of nonfatal heart attack. The study included 2,014 case patients with a first acute nonfatal heart attack and 2,014 controls, living in Costa Rica between 1994 and 2004. The genotypes of the participants were determined. A food frequency questionnaire was used to assess the intake of caffeinated coffee.

Fifty-five percent of cases (n = 1,114) and 54 percent of controls (n = 1,082) were carriers of the slow *1F allele. For carriers of the slow *1F allele, those who drank 2 to 3 cups of coffee a day had a 36 percent increased odds of heart attack; those who drank 4 or more cups per day had a 64 percent increased odds of heart attack. Corresponding consumption for individuals with the rapid *1A/*1A genotype resulted in the reduced odds of heart attack by 22 percent and 1 percent, respectively.

Among the slow metabolizers, younger individuals showed an increased risk. The risk associated with drinking 4 cups/d or more compared with less than 1 cup/d increased from 2-fold for individuals younger than 59 years to more than 4-fold for those younger than 50 years. Among the fast metabolizers who were younger than 59 years of age, those who drank 1 cup/d or 2 to 3 cups per day had a reduced odds of a heart attack by 52 percent and 43 percent, respectively.

"In summary, consistent with most case-control studies, we found that increased coffee intake is associated with an increased risk of nonfatal MI. The association between coffee and MI was found only among individuals with the slow CYP1A2*1F allele, which impairs caffeine metabolism, suggesting that caffeine plays a role in the association," the authors conclude.

#4: Scientists Discover How Coffee Can Reduce Risk Of Pancreatit Author: adediosLocation: Angel C. de Dios PostPosted: Mon Mar 20, 2006 7:57 pm
Source: University of Liverpool

Posted: March 20, 2006

Scientists Discover How Coffee Can Reduce Risk Of Pancreatitis

Scientists at the University of Liverpool have found how coffee can reduce the risk of alcohol-induced pancreatitis.

Pancreatitis is a condition in which the pancreas becomes inflamed, causing severe abdominal pain. It is often triggered by alcohol consumption which causes digestive enzymes to digest part of the pancreas.

Scientists have known for some time that coffee can reduce the risk of alcoholic pancreatitis, but have been unable to determine how. Researchers at the University have now discovered that caffeine can partially close special channels within cells, reducing to some extent the damaging effects of alcohol products on the pancreas.

Professor Ole Petersen and Professor Robert Sutton, from the University's Physiological Laboratory and Division of Surgery, have found that cells in the pancreas can be damaged by products of alcohol and fat formed in the pancreas when oxygen levels in the organ are low. Under these conditions, excessive amounts of calcium are released from stores within the cells of the pancreas. Special organelles, called mitochondria, also become damaged and cannot produce the energiser that normally allows calcium to be pumped out of the cells. The excess calcium then activates protein breakdown, destroying the cells in the pancreas.

Professor Petersen explains: "The primary cause of the build up in calcium ion concentration is movement of calcium ions from a store inside the cells into the cell water through special channels in the store membrane. We have found that caffeine, present in drinks such as coffee can at least partially close these channels. This explains why coffee consumption can reduce the risk of alcoholic pancreatitis. The caffeine effect, however, is weak and excessive coffee intake has its own dangers, so we have to search for better agents.

"At the moment there is no specific pharmacological treatment for pancreatitis. As a result of this research however, we can, for the first time, begin to search for specific chemical agents that target the channels causing the excessive liberation of calcium ions inside the cells, which is where the problem originates. We are also hoping that these findings can be used to warn against the dangers of binge drinking. Some of the effects of the non-oxidative alcohol products on isolated pancreatic cells cannot be reversed, explaining why excess alcohol intake can be so dangerous."

The research by Professor Petersen and Professor Sutton, which is supported by the Medical Research Council, is published in TRENDS in Pharmacological Sciences and Gastroenterology.

#5: Coffee, black, decaf and a little llama on the side Author: adediosLocation: Angel C. de Dios PostPosted: Sat May 13, 2006 7:09 am
Washington University School of Medicine
11 May 2006

Coffee, black, decaf and a little llama on the side
St. Louis, May 11, 2006 -- Three llamas and two camels have provided a way to tell whether your waiter swapped regular coffee for decaf in your after-dinner cup. Using the heat-resistant antibodies these camels and llamas make, researchers at Washington University School of Medicine in St. Louis are developing a quick test for caffeine that works even with hot beverages.
The researchers plan to adapt their technology to a simple test ("dipstick") that can be used to check for caffeine in a variety of drinks. Their research will appear in the June 1 issue of the American Chemical Society's journal Analytical Chemistry.

Caffeine can cause restlessness, irritability, dehydration or heart arrythmias, and those who are highly sensitive to caffeine can feel its stimulant effects for as long as 20 hours. In addition, some medicines adversely interact with caffeine.

"We believe our test would be the first consumer test for caffeine and would be beneficial for anyone wishing to avoid caffeine for health or personal reasons," says senior author Jack H. Ladenson, Ph.D., the Oree M. Carroll and Lillian B. Ladenson Professor of Clinical Chemistry and director of the Division of Laboratory Medicine.

Interestingly, the key to the caffeine test comes from llamas and camels -- pack animals that have transported caffeinated commodities such as coffee, tea and cocoa for centuries. These camelids happen to be among the few creatures whose immune systems can produce antibodies that aren't destroyed at the high temperatures common to brewed beverages.

The researchers reasoned that if they could create heat-resistant camelid antibodies that reacted to caffeine, they could potentially build a durable assay suitable for use almost anywhere. They gave intramuscular injections of a caffeine-linked protein to three llamas and two camels to elicit an immune response to caffeine. They found that blood from the animals contained antibodies that were heat-stable and reactive to caffeine.

The most stable version of the caffeine-specific antibody, which came from a llama named Very Senorita, recovered 90 percent of its activity after exposure to 194 degrees Fahrenheit (90 degrees centigrade) -- about the temperature of a really hot cup of coffee. A similar antibody produced from mice broke down at 158 degrees Fahrenheit.

A lab test using the caffeine-specific antibody accurately measured the amount of caffeine in coffee and cola drinks. The antibody cross-reacted very little with theophylline or theobromine, the caffeine-like compounds in teas, so the caffeine content of teas could be measured without interference from these substances.

"Now that we've isolated the sequence of this stable anti-caffeine antibody, we can produce copies in the lab to develop a convenient caffeine test--we don't need to rely on the animals," Ladenson says. "And unlike other methods for measuring caffeine, which require large and expensive laboratory equipment, this test is potentially adaptable to a format that people could carry with them,"

An eight-ounce cup of regular coffee has about 80 to 280 milligrams of caffeine, and a similar-sized cup of black tea can vary from 60 to 100 milligrams, depending on brewing time. Cola drinks, both diet and regular, typically contain between 30 to 50 milligrams of caffeine in each 12-ounce can, while high-caffeine sodas can have as much as 80 milligrams per can. In comparison, decaffeinated coffee generally has only about 5 milligrams of caffeine.

The caffeine test has shown accuracy that compares well with measurements made with sophisticated equipment. Ladenson and his colleagues are currently working to develop a portable, point-of-consumption test.

Ladenson's laboratory is well-known for having developed the first practical blood test for troponin I, a protein that is released into the blood after a heart attack. This test, along with a test for a form of the enzyme creatine kinase that was also developed in Ladenson's lab, is widely used to determine whether patients with certain symptoms have had a heart attack.

Ladenson RC, Crimmins DL, Landt Y, Ladenson JH. Isolation and characterization of a thermally stable recombinant anti-caffeine heavy-chain antibody fragment. Analytical Chemistry June 1, 2006.

Washington University School of Medicine's full-time and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children's hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked fourth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children's hospitals, the School of Medicine is linked to BJC HealthCare.

#6: Negative effects of caffeine are stronger on daytime sleep Author: adediosLocation: Angel C. de Dios PostPosted: Mon Oct 02, 2006 1:50 pm
University of Montreal

Negative effects of caffeine are stronger on daytime sleep than on nocturnal sleep

Montreal, October 2, 2006 -- A new study at the Université de Montréal has concluded that people drinking coffee to get through a night shift or a night of studying will strongly hurt their recovery sleep the next day. The study published in the current issue of Neuropsychopharmacology was conducted by Dr. Julie Carrier from the Department of Psychology at the Université de Montréal. Dr. Carrier runs the Chronobiology Laboratory at the Hôpital du Sacré-Coeur de Montréal.

"We already knew that caffeine has important effects on nocturnal sleep. It increases the time taken to fall asleep, it increases the amount of awakenings, and it decreases the amount of deep sleep. We have shown that these effects of caffeine on sleep are way stronger when taken at night prior to a daytime recovery sleep episode than in the evening before a nocturnal sleep episode."

"Caffeine makes daytime sleep episodes too shallow to override the signal from the biological clock that tells the body it should be awake at this time of day," explains Dr. Carrier. "We often use coffee and other sources of caffeine during the nighttime to counteract sleepiness generated by sleep deprivation, jet lag, and shift-work. However, this habit may have important effects when you then try to recuperate during daytime."

Thirty-four moderate caffeine consumers participated in both caffeine (200 mg) and placebo (lactose) conditions in a double-blind crossover design. Seventeen subjects followed their habitual sleep–wake cycle and slept in the laboratory during the night (Night), while 17 subjects were sleep deprived for one night and recovery sleep started in the morning (DayRec). All subjects received a capsule of 100 mg of caffeine (or placebo) 3 hours before bedtime, and the remaining dose 1 hour before bedtime. Compared to placebo, caffeine lengthened sleep latency, increased stage 1, and reduced stage 2 and slow-wave sleep (SWS) in both groups. However, caffeine reduced sleep efficiency more strongly in the DayRec group, and decreased sleep duration and REM sleep only in that group.

The study of Dr. Carrier was supported by scholarships and grants from the Canadian Institutes of Health Research (CIHR), the Fonds de Recherche en Santé du Québec (FRSQ), and the Natural Sciences and Engineering Research Council of Canada (NSERC).

About the Université de Montréal
Founded in 1878, the Université de Montréal today has 13 faculties and together with its two affiliated schools, HEC Montréal and École Polytechnique, constitutes the largest centre of higher education and research in Québec, the second largest in Canada, and one of the major centres in North America. It brings together 2,400 professors and researchers, accommodates more than 55,000 students, offers some 650 programs at all academic levels, and awards about 3,000 masters and doctorate diplomas each year.

#7: Caffeine may prevent heart disease death in elderly Author: adediosLocation: Angel C. de Dios PostPosted: Fri Feb 23, 2007 9:05 am
SUNY Downstate Medical Center
22 february 2007

Caffeine may prevent heart disease death in elderly

Habitual intake of caffeinated beverages provides protection against heart disease mortality in the elderly, say researchers at SUNY Downstate Medical Center and Brooklyn College.

Using data from the first federal National Health and Nutrition Examination Survey Epidemiologic Follow-up Study, the researchers found that survey participants 65 or more years old with higher caffeinated beverage intake exhibited lower relative risk of coronary vascular disease and heart mortality than did participants with lower caffeinated beverage intake.

John Kassotis, MD, associate professor of medicine at SUNY Downstate, said, "The protection against death from heart disease in the elderly afforded by caffeine is likely due to caffeine's enhancement of blood pressure."

The protective effect also was found to be dose-responsive: the higher the caffeine intake the stronger the protection. The protective effect was found only in participants who were not severely hypertensive. No significant protective effect was in patients below the age of 65.

No protective effect was found against cerebrovascular disease mortality – death from stroke – regardless of age.

This research was published by The American Journal of Nutrition in its February 2007 issue.

#8: Caffeine Nation Marches On Author: adediosLocation: Angel C. de Dios PostPosted: Thu Mar 01, 2007 8:59 am
Caffeine Nation Marches On
By Michelle Heimburger
Thu, March 1, 2007, 12:01 am PST

Today kicks off Caffeine Awareness Month and we're buzzing with excitement at the thought of 31 days dedicated to our favorite addiction. In the spirit of the event, we wonder, are you aware of caffeine?

For the full article:


#9: Coffee consumption may lower blood uric acid levels -- The p Author: adediosLocation: Angel C. de Dios PostPosted: Fri May 25, 2007 8:37 am
John Wiley & Sons, Inc.
25 May 2007

Coffee consumption may lower blood uric acid levels -- The precursor of gout

High uric acid levels in the blood are a precursor of gout, the most common inflammatory arthritis in adult men. It is believed that coffee and tea consumption may affect uric acid levels but only one study has been conducted to date. A new large-scale study published in the June 2007 issue of Arthritis Care & Research (http://www.interscience.wiley.com/journal/arthritiscare) examined the relationship between coffee, tea, caffeine intake, and uric acid levels and found that coffee consumption is associated with lower uric acid levels but that this appears to be due to components other than caffeine.

Coffee is one of the most widely consumed beverages in the world; more than 50 percent of Americans drink it at the average rate of 2 cups per day. Because of this widespread consumption, its potential effects have important implications for public and individual health. Led by Hyon K. Choi, of the University of British Columbia in Vancouver, Canada, the current study was based on the U.S. Third National Health and Nutrition Examination Survey, conducted between 1988 and 1994. It included over 14,000 men and women at least 20 years old who consented to a medical exam in which blood and urine specimens were obtained. Coffee and tea consumption were determined based on responses to a food questionnaire that assessed intake over the previous month. Researchers estimated the amount of caffeine per cup of coffee or tea using data from the U.S. Department of Agriculture.

The results showed that levels of uric acid in the blood significantly decreased with increasing coffee intake, but not with tea intake. In addition, there was no association between total caffeine intake from beverages and uric acid levels. These results were similar to those found in the only previous study on the topic, which was conducted in Japan. Interestingly, there was an association between decaffeinated coffee consumption and uric acid levels. "These findings suggest that components of coffee other than caffeine contribute to the observed inverse association between coffee intake and uric acid levels," the researchers state.

A recent study found that coffee was associated lower C peptide levels (a marker of insulin levels). The researchers in the current study suggest that because there is a strong relationship between insulin resistance and elevated uric acid levels, the decreased insulin levels associated with coffee consumption may lead to lower uric acid levels. Coffee is also a major source of chlorogenic acid, a strong antioxidant, which may improve insulin sensitivity. Chlorogenic acid also helps inhibit glucose absorption in the intestine; in another study decaffeinated coffee seemed to delay intestinal absorption of glucose and increase concentrations of glucagon-like peptide 1, which is well known for its beneficial effects on insulin secretion and action. The researchers note further that their results could be due to an effect of non-caffeine components found in coffee, which would also explain why coffee affected uric acid levels but tea did not.

Article: "Coffee, Tea, and Caffeine Consumption and Serum Uric Acid Level: The Third National Health and Nutrition Examination Survey," Hyon K. Choi, Gary Curhan, Arthritis Care & Research, June 2007; 57:5; (DOI: 10.1002/art.22762).

#10: A Gut Feeling about Coffee Author: adediosLocation: Angel C. de Dios PostPosted: Sat Jul 28, 2007 7:14 am
Week of July 28, 2007; Vol. 172, No. 4

A Gut Feeling about Coffee
Janet Raloff

Earlier this year, Spanish researchers unveiled coffee as a notable source of soluble fiber. Now, a team in Germany confirms the finding and shows that beneficial gut microbes can easily digest the coffee-bean fiber left in brewed liquid and extract its energy for their growth. Because the waste products of that digestion—also called fermentation—can repel some disease-causing bacteria, the new data suggest that coffee drinking might represent more of a benefit than a vice.

For the full article:


#11: Exercise Plus Coffee May Ward Off Skin Cancer Author: adediosLocation: Angel C. de Dios PostPosted: Mon Jul 30, 2007 2:16 pm
Exercise Plus Coffee May Ward Off Skin Cancer
By Kathleen Doheny, HealthDay Reporter

posted: 30 July 2007 02:52 pm ET

(HealthDay News) -- A coffee habit, coupled with regular exercise, may help prevent skin cancers better than either factor alone, new research suggests.

The study was done only with animals, however, and it's not a reason to abandon standard sun-protection habits.

For the full article:


#12: Chemists Find What Makes Coffee Bitter Author: adediosLocation: Angel C. de Dios PostPosted: Tue Aug 21, 2007 1:06 pm
Chemists Find What Makes Coffee Bitter
By Jeanna Bryner, LiveScience Staff Writer

posted: 21 August 2007 01:33 pm ET

Chemists have figured out why dark-roasted coffees are so bitter, a finding that could lead to a smoother cup of java.

Using chemical analyses and follow-up taste tests by humans trained to detect coffee bitterness, the scientists discovered the compounds that make coffee bitter and also how they form.

"Everybody thinks that caffeine is the main bitter compound in coffee, but that's definitely not the case," said study leader Thomas Hofmann, a professor of food chemistry and molecular sensory science at the Technical University of Munich in Germany.

For the full article:


#13: The Buzz about Caffeine Author: adediosLocation: Angel C. de Dios PostPosted: Sat Sep 22, 2007 10:10 am
The Buzz about Caffeine
Emily Sohn

Sept. 19, 2007

You're drinking lots of cola at a party, when suddenly it hits: You! Are! Hyper! You jump around. You talk too fast. You laugh so hard that soda squirts out of your nose. Later, you can't fall asleep, and the next day, you're tired and feel awful. Sound familiar?

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