Have you noticed that you cannot pick up a magazine or newspaper that doesn’t have an article touting some miraculous benefit attributed to coffee? “Keep your brain from aging! – drink 3 cups of coffee daily and you’ll boost the flow of nutrient and oxygen rich blood to your brain”. Then pick up another magazine “Your daily cup of Joe reduces the risk of type 2 diabetes and Alzheimer’s”. Not as prevalent, but they exist are warning articles “Limit coffee to protect your eyes - drinking more than three cups of caffeinated coffee daily increases the risk of glaucoma and vision loss.”. “Coffee consumption increases risk of high blood pressure and heart failure“. Confused yet? Is coffee good or bad for you? How much is good? How much is bad? Does coffee prevent cancer or cause cancer? I’ve been reviewing the plethora of research for over a month to prepare for this article and found research conclusions that seemingly contradicted each other. I became overwhelmed and perplexed at what appeared to be ambiguous results - until I had an Ah Ha! moment … and I’m hoping this article will clarify the coffee conundrum for you too.
When one considers that coffee is the leading worldwide beverage after water, that its trade exceeds US $10 billion worldwide, that people consume approximately 500 billion cups annually, and that coffee is the second largest traded commodity worldwide after petroleum; 1. No wonder it’s one of the most controversial and scientifically researched beverages on the planet!
Coffee originated in Ethiopia and was exported to Yemen in the 15th century. The first credible record of roasting and brewing appears in Arabia around mid-15th century. Prior to that time the berries were fermented into a wine to be used in native religious ceremonies. Through the ensuing centuries coffee has been used in some spiritual practices and banned by other religions. It’s been accused of being a heretical substance, it’s been banned by jurists, scholars, religious sects, governments, countries and empires. The Church of Jesus Christ Latter-Day Saints holds that it is both physically and spiritually unhealthy to consume coffee. It does not identify coffee by name, but includes the statement that "hot drinks are not for the belly. Seventh-day Adventists avoid all stimulants. Coffee was even prohibited at Passover, until 1923 when upon petition by Maxwell House it was reclassified as a berry rather than a legume. 2. You can read more on coffee’s rich and fascinating history here: http://en.wikipedia.org/wiki/Coffee
Benefits and Risks
On the benefit side, coffee does have nutritional value, containing important antioxidants, polyphenols, proteins and fiber. Coffee’s main ingredient is caffeine which is the source of most of the controversy. 3. Caffeine is the most commonly consumed psychoactive substance in the world with 90% of Americans consuming it daily in one form or another. 4
Americans get more antioxidants from coffee than from any other food or beverage. 5.
Say what? Now isn’t that SAD?! (Standard American diet), Americans getting more antioxidants from coffee than fruits and veggies?
In reviewing the research, many meta-analyses highlighted the benefits of coffee consumption with lower risk of colorectal, liver, renal, ovarian, pancreas, esophagus, endometrial, and pharyngeal cancers. The mechanism behind the anticancer properties may have more to do with coffee’s antioxidants, chlorogenic acids, cafestol and kahweol than the caffeine, as decaffeinated coffee has shown some positive influences as well. Contrary studies associate coffee consumption to increased risk of breast, laryngeal, lung, pancreatic, ovarian and prostate cancer. 1
Scientists seem to be in agreement that many components in coffee also have health benefits reducing risk of diabetes and other metabolic syndromes. Coffee and caffeine may also reduce the risk of dementia, Parkinson’s and Alzheimer’s disease.1
On the risk side, science seems to be in agreement about coffee’s detrimental effect on hypertension and gastroesophageal reflux disease (GERD). However, ambiguities and hot debate still persists as to the effects on human health in in the area coronary heart disease. 1.
Moderate coffee consumption may be of benefit because it seems to be associated with lower coronary heart disease risk, whereas heavy consumption is associated with a significant increase of the risk.6. In a 2005 study, it was concluded that chronic coffee consumption unfavorably affects arterial stiffness and wave re-flections 7. (two predictors of heart disease).
It is difficult to link precise intake levels of caffeine to specific health effects because tolerance to caffeine differs widely from person to person. For healthy adults, a small amount of caffeine may have positive effects, such as increased alertness or ability to concentrate. However, some people are more sensitive to caffeine. For them, a small amount could cause insomnia, headaches, irritability and nervousness. 8.9.
Now, here is where my Ah Ha! moment happened, I came across research that isolated a “coffee gene” - CYP1A2. (Technical term polymorphism in the metabolic enzyme cytochrome P-450 or Genetic polymorphism CYP1A2). CYP1A2, is one of the genes implicated in coffee metabolism, it makes a difference on how fast or how slow you metabolize coffee (and many other drugs). This is some very interesting research, and potentially can explain why coffee is good for some and bad for others for and it is this gene that is associated with risk of myocardial infarction in caffeine users. 4 Fast metabolizers seem to receive benefits while slow metabolizers, well, it can be risky. 4, 10
Caffeine is broken down and cleared by the liver, and our genetic makeup shapes how quickly and effectively we can do this. On one hand, “slow” metabolizers of caffeine don’t process caffeine effectively. These are people who are adversely affected by caffeine, get the jitters, and are wired for up to nine hours after consumption. Others just get a boost in energy and alertness for a couple of hours; they are considered “fast” metabolizers of caffeine. 11
About half of the population has a variation of this gene that causes a person to be a slow metabolizer of caffeine. This means that the caffeine remains in the blood a long time. The result is that blood pressure and heart rate go up, and to remain elevated for a long time. In contrast, there are other people who have a form of the gene causing them to be rapid metabolizers. These people are able to rid the body of caffeine quickly and barely feel a heart palpitation no matter how much coffee they drink.12
With the identification of this new gene, some scientists now suggest that those who have the slow metabolizer gene should avoid coffee, if they have high blood pressure. 12.________________________________________
This is the technical way to explain the gene:
Caffeine is metabolized in the body by the enzyme Cytochrome P450 1A2 (CYP1A2). Every person has two copies of the gene which makes the enzyme CYP1A2 (one copy from each parent). There are 2 variations of this gene which affect how quickly a person metabolizes caffeine. The CYP1A2*1A variety (“allele”) makes an enzyme that metabolizes caffeine very rapidly. However, the CYP1A2*1F allele metabolizes caffeine slowly. The difference between these two alleles is one single nucleotide, an A to C substitution at position 734 of the CYP1A2 gene. Individuals who have two copies of the fast CYP1A2*1A allele are fast caffeine metabolizers; whereas people who have at least one copy of the slow CYP1A2*1F allele are slow caffeine metabolizers. 13
The only way to know if you are a slow or fast metabolizer is through genetic testing. As 50% of the population are potentially slow metabolizers, heavy coffee consumption can be playing Russian roulette with your health.
On the risk side of drinking coffee:
Depending on coffee for energy, you may be masking underactive adrenal function or even adrenal exhaustion. It’s like the scene in Gone with the Wind where Scarlet O’Hara is beating the dying horse to get up. If you are using caffeine this way you may be reducing your adrenals’ ability to react to stress, whether it’s physical, emotional or psychological.
Adrenal glands contribute about 35% of female hormones pre-menopausal and almost 50% post menopausal – ladies you do not want to enter menopause with depleted adrenals!
Without proper functioning of adrenal glands pregnancy cannot occur. 14
Pregnant women consuming more than 6 cups/day of coffee are more vulnerable to abortion and lower fetal weight. 1 Accordingly, pre and post-menopausal women would be wise to avoid or limit coffee, as well as those women wishing to get pregnant and those who are pregnant.
Another extremely important topic, which is out of the scope of this article, is the worry of caffeine use in children. Although once relatively restricted to use among adults, caffeine-containing drinks are now consumed regularly by children. In addition, some caffeine-containing beverages are specifically marketed to children as young as 4 years of age. Knowledge of the effects of caffeine use on behavior and physiology of children remains understudied and poorly understood 4. (exactly - who’d offer up their children for such a study?).
So what’s the take home out of all this? If you enjoy the taste and the energy buzz you get from coffee, moderation is key (1-3 cups or 400 mg. caffeine) maximum per day.
Listen to your body – if you are a slow metabolizer and getting “side-effects” from coffee even 1 cup per day may be too much for you! Keep in mind that caffeine is a drug. Regular consumption is addictive. Should you choose to quite coffee, you’ll suffer withdrawal symptoms that can last days. Herb tea is the way to go!
1. Butt Masood, Sultan Tauseef. Coffee and its Consumption: Benefits and Risks benefits and Risks Critical Reviews in Food Science and Nutrition, 2011 51:4, 363-373.
2. Excerpt from Wikipedia http://en.wikipedia.org/wiki/Coffee#Prohibition
4. Yang Amy, Palmer Abraham, de Wit Harriet. Genetics of caffeine consumption and responses to caffeine. Psychopharmacology 2010; 211:245-257.
6. Panagiotakos Demosthenes, Pitsavos Christos, Chrysohouu Christina et al. The J-Shaped Effect of Coffee Consumption on the Risk of Developing Acute Coronary Syndromes: The CARDIO2000 Case-Control Study. J. Nutr. 2003;133/10:3228-3232.
7. Vlachopoulos Charalambos, Panagiotakos, Demosthenes, Ioakeimidis Nikolaos et al. Chronic coffee consumption has a detrimental effect on aortic stiffness and wave reflections Am J Clin Nutr 2005:81:1307-1312
14. Bogaart, Eric. Literature Review Adrenal Fatigue – The 2001 Stress Syndrome: The Etiology, Symptoms and Treatments (2004)
15. Neuroscience and Biobehavioral Reviews 33 (2009) 793–806