Your Cup of Coffee - 2
By Dr. Rizwana Rahim
Coffee happens to be the first commodity in the US market which is being monitored by independent groups to ensure that the coffee producers in Asia, Africa, Latin America and the Caribbean receive a fair price for their product and operate under fair labor conditions, not “sweatshops in the fields.”
‘Fair Trade Certified’ coffee is part of an international movement (already quite strong in the UK and other EU countries), and there are over 100 US companies, including Starbucks, that have licensing agreements with TransFair to provide such coffee. Fair Trade certification indicates that the following international criteria have been met: a minimum price $1.26 per pound of coffee, regardless of volatile market (amounting to a living wage), needed credit at fair price and long-term relationship, and community development with investments in their health care, education, environmental help and economic independence.
This is, obviously, a social justice issue, with significant environmental sustainability issues. Consider the enormous and growing gulf between what you pay for a cup of gourmet coffee and the price paid to the coffee farmers ($0 .60 to 0.70/ pound, with below $0.50/pound in August 2001). Fair Trade Coffee emphasizes organic and shade grown, where possible. The 2006 documentary, “Black Gold” illustrates different facets of this complex issue, including the reason/s why we pay 25-times more for a cup of coffee than what an Ethiopian coffee farmer gets for it.
Coffee is a stimulant, and the substance which is most responsible for the ‘kick’ is an alkaloid called caffeine or 1, 3, 7-trimethylxanthine, perhaps the most widely used pharmacologically active compound in the world. Besides coffee, caffeine occurs naturally in over 60 plant species, including tea, cocoa beans/chocolate products. It is also added to many soft drinks and a number of drugs in common clinical use. A five-ounce (150 ml) cup of ground roasted coffee has about 85 mg caffeine; caffeine levels in some other beverages and products are: 60 mg (in 150-ml instant coffee), 3 mg (decaffeinated coffee, same amount); 30 mg (tea bag or loose tea; concentration increases with stewing time), and 4 mg (hot chocolate). These FDA standards are set for various commercial products. Over 800 volatile compounds are found in the aroma of roasted coffee.
Caffeine stimulates the central nervous system, and is mildly addictive. It is completely absorbed from the gastrointestinal tract within 45 minutes after its intake, with its plasma concentrations reaching a peak in 15-120 minutes. Its ‘half-life’ in plasma (i.e., the time to reduce its plasma concentration by 50%) is between 2.5 to 4.5 hours in adult males; in smokers, its half-life is reduced by 30-50% (i.e., it is removed from smokers’ plasma faster by that percentage). Almost all of the caffeine (97% of the intake) is metabolized, and excreted in urine.
The two species used (C. arabica and canephora) differ in caffeine content as well as flavor/taste. Typically, C. arabica has lower concentrations of caffeine (0.8 to 1.4%) than C. canephora (1.7 to 4.1%); the latter is used often to increase caffeine concentration in a blend. C. arabica costs more, is considered of higher quality and tastes different from C. canephora. These two species also require different cultivation conditions: C. canephora is indigenous to equatorial African lowlands and grows well below 700-meter elevation, and C. arabica needs less rain and higher elevations, between 1,000 and 2,000 meter.
Although many people enjoy a cup or more of coffee, some for health reasons would rather not have the ‘jolt’ that caffeine generally gives, and they would rather have the ‘decaffeinated’ coffee. Commercially, decaffeination was achieved first in Germany in the early 20th century. Now, caffeine is selectively removed or extracted out from the green coffee beans (before roasting) by several methods, using water, liquid CO2 or solvents like methylene chloride and ethyl acetate.
Regardless of the method used, decaffeinated coffee is not totally free of caffeine, because a tiny fraction of caffeine always remains unextractable: in the US, the average standard amount removed is 97-98% of the total caffeine; or, the caffeine content is reduced to 0.1% or less in roasted coffee beans (dry wt basis), corresponding to 2-4 mg caffeine in an average cup of decaffeinated coffee, and to 0.3% or less in soluble/instant coffee. In case organic solvents are used in the process, solvent levels in the final product have to be less than 2 parts per million. Compare these levels to what is found in other beverages we consume: an 8-oz Drip coffee, 115-175 mg caffeine; tea, 40-60 mg; a 12-oz can of coca cola classic, about 34 mg caffeine; 7-Up or Sprite, Zero caffeine; 8.2 –oz Red Bull 80 mg.
Whatever method of decaffeination used, the decaffeinated green coffee must contain less than 0.1 % caffeine (dry weight basis) to comply with EC regulations.
The ‘lnstant’ coffee, on the other hand, is made by freeze drying a coffee brew, which removes the water, to produce powder or granules which are re-converted to the brew by adding hot water.
Caffeine does cause significant health and behavioral effects. A lot of research done since 1970s has produced some ambiguous or inconclusive results or results that weren’t confirmed later, for instance, links to increased pancreatic cancer, heart attacks, birth defects, miscarriage, osteoporosis, and other adverse health effects. Not an uncommon problem with epidemiological studies! Various US and international agencies, including Harvard University Health newsletters, have summarized an update of the latest medical thinking on effects of caffeine. See these links: http://www.medicinenet.com/caffeine/article.htm ; http://www.bbc.co.uk/health/healthy_living/nutrition/drinks_caff.shtml ; http://www.cosic.org/ ; http://www.ico.org http://www.health.harvard.edu/press_releases/coffee_health_benefits.htm .
Caffeine does cause some cardiovascular effects (increased heart rate, blood pressure, and irregular heartbeat, sometimes). Long-term studies have also shown that coffee may not increase the risk for high blood pressure, as previously thought. Used in moderation (few cups a day for most healthy people), it could even have some health benefits, according to the Harvard newsletter.
Among regular coffee consumers, the risk for type 2 diabetes was to be lower than coffee-non-drinkers; this emerged from 7 out of 10 such studies that followed large groups of people for many years, including Finnish twins and American nurses, and an 11-year study of 28,000 postmenopausal women in Iowa. Some chemicals in coffee may help lower blood sugar levels. Studies in which a large number of groups are monitored for a long time and carefully for intended biological indicators tend to produce reliable results. Coffee may also reduce the risk of developing gallstones, colon and rectal cancer, improve cognitive function, and reduce the risk of liver damage and Parkinson's disease.
Studies with population groups in the United States, Japan, Europe and Norway suggest coffee protects the liver from the effects of alcohol, coffee acting as a buffer against alcohol’s known damages.
A study with 125,500 members of the Kaiser Permanente health plan, showed that in heavy alcohol drinkers the risk of cirrhosis was reduced by 20% per cup of coffee a day; four cups correlated with an 80 percent risk reduction. Clinical chemistry showed healthier liver enzyme levels in those who consumed both coffee and alcohol. Researchers have also found that coffee drinkers were 50% less likely to get liver cancer than non-drinkers.
Coffee contains two chemicals, kahweol and cafestol, that tend to raise cholesterol levels, but they are trapped in coffee filters. So, non-filtered coffee users may be exposed to this risk. Coffee seems to protect men, but not women, against Parkinson’s disease; one explanation of this gender difference is perhaps a result of estrogen using the enzymes that caffeine also needs for metabolism.
So, like in many other things in life, ‘moderation’ is also the word for coffee consumption.