Coffee: The Highs & Lows of the Morning Cup of Joe
Sounds of a percolating machine, the smell of a favorite roasted bean, and a warm mug in the hands, is how over half of American adults begin their day. That’s right, we’re talking coffee here folks! There are an estimated 170 million coffee drinkers in the U.S. In fact, the United States consumes more coffee than any other country, importing about 2.5 million pounds per year. The average citizen consumes at least two cups a day, which equals approximately 22 gallons annually per person. Currently, the U.S. coffee consumption rate is at its highest point in 30 years, due at least in part to an increase in the number and variety of coffee drinks available. Today, there are flavored coffees, mochas, cappuccinos, lattes, and espressos found on nearly every corner. Coffee accounts for about three quarters of daily caffeine intake. An important question then, is what affect is all this coffee drinking having on our health? Coffee has been touted in the news of late for some potential health benefits, yet it has many known negative side effects as well. Let’s take a closer look our national addiction.
The Potential Upside
- · Protection against Parkinson’s Disease—Research shows that caffeine prevents the loss of dopamine producing cells which occurs in Parkinson’s Disease, but scientists are not sure how the process works or what other factors may account for the coffee-Parkinson’s connection. Research is ongoing.
- · Protection from Diabetes—A protective effect appears only to work in those who do not already have diabetes. One current theory for the protection provided is the fact that moderate-to-heavy coffee drinkers tend to drink fewer sugary sodas, which are known diabetes contributors. Some studies also show a benefit to decaffeinated coffee and tea consumption, which suggests a benefit beyond just the caffeine (possibly the antioxidant content). More research is needed. It is worth noting that coffee’s benefit in relation to diabetes is found with high consumption (4-5 + cups a day), which may bring other negative complications.
- · Sharpens the Mind—Caffeine offers a short-term energy boost and may sharpen the mind temporarily, particularly if drowsiness is present. However, these benefits are short-lived. The crash after the caffeine wears off may leave a person more tired than before consumption.
Excessive caffeine intake can lead to: a fast heart rate; frequent urination; nausea; vomiting; restlessness; anxiety; depression; tremors and may contribute to the following:
- · Miscarriages & Birth Defects—While more study is needed, some recent work has suggested a link between coffee and low-birth weight in babies. The connection is stronger as caffeine consumption increases. Low birth weight is linked to an increased chance of death in early infancy. Studies have also shown a potential connection between caffeine intake and miscarriage. Most of the studies linking coffee consumption and miscarriage or low birth weight are focused on a daily intake of at least 2-3 cups per day. The National Institute of Child Health and Human Development recommends expectant mothers limit their coffee intake to no more than one or two cups a day, if at all. Avoiding coffee completely during pregnancy is considered the best practice.
- · Osteoporosis—Caffeine extracts calcium from bones. The more coffee a person drinks, the more calcium is removed. If you are a regular coffee drinker, be sure to replace lost calcium by eating a variety of calcium rich foods and get regular weight-bearing exercise to maintain bone strength.
- · Heart Health Issues—Several studies have shown that coffee elevates homocysteine levels, which is a known risk factor for heart disease. Coffee may also increase cholesterol levels. While these increases may be small or moderate in most coffee drinkers, people with pre-existing heart conditions or who drink four or more cups of coffee a day, may be at some risk and should monitor their coffee intake. Coffee also makes the heart work harder by elevating the heart rate by an average of three beats per minute.
- · Blood Pressure—Caffeine damages blood vessels by making them less elastic, which increases blood pressure by an average of four points. While this increase may not be an issue to most, it could be significant to those with pre-existing hypertension (high blood pressure).
- · Stress—Caffeine causes an increase in the stress hormone epinephrine, which may aggravate anxiety conditions.
- · Sleep Disruption—Caffeine is a stimulant and therefore not conducive to sleep. One-eighth of the caffeine content from a cup of coffee is still present in the body 12 hours later, so a percentage of caffeine ingested in the afternoon, will still be in the body at bedtime.
- · Glucose Elevation—Duke researchers, among others, have conducted tests that show caffeine extends the time glucose levels are raised after a meal. For this reason, diabetics may want to cut back on or avoid caffeine.
What about Decaf?
To avoid some of the negative side effects mentioned above, decaffeinated coffee is an option; however, there is growing evidence that decaffeinated coffee raises the risk of developing rheumatoid arthritis (RA). The risk appears to go up the more decaffeinated coffee is consumed. It was reported at the annual meeting of the American College of Rheumatology that drinking more than one cup of decaf a day raises the risk of RA four-fold.
Putting it all Together
Coffee is a major part of life and culture for many and should be evaluated on an individual basis. For some, coffee may be of limited benefit under certain circumstances if consumed moderately (1-2 cups a day), but for others, it may pose unwanted risks. Consult a trained medical professional or a nutritionist for more information for particular conditions.
- American College of Rheumatology
- The Center for Science in the Public Interest
- The American Journal of Clinical Nutrition
- The National Institute of Child Health and Human Development
- Psychosomatic Medicine
- Carnegie Mellon University (www.mass-spec.chem.cmu.edu)
- Scientific American
- Archives of Internal Medicine