Coffee has been the chosen beverage for literally millions of people around the world. So why is the same substance literally a life saver for some people and a potentially deadly drug to others? Thanks to the science of genetics we now understand the concept of different strokes for different folks. It turns out that the enzyme that breaks down caffeine (CYP1A2) as caffeine passes through the liver, is genetically determined by either slow, medium, fast, or ultrafast genes. In other words, if you are a slow metabolizer one cup of caffeinated coffee may be too much, and if you happen to have ultrafast genes you may be able to drink 4 cups of coffee per day and at bedtime, and still sleep soundly all night long.
A study was done in Costa Rica looking at over 2,014 men who had experienced a nonfatal myocardial infarction (MI or heart attack) and another 2,014 as controls living in Costa Rica between 1994 and 2004. All were genotyped to determine if they were slow, medium, fast, or ultrafast in metabolizing (breaking down) caffeine. Results were interesting in that only men who were slow metabolizers of caffeine had experienced acute nonfatal heart attacks. Furthermore, the men in the other groups (medium, fast, and ultrafast) who drank 1-4 cups of coffee per day were associated with a lower risk of MI compared to those taking one or less cups of coffee per day. The implication is that coffee may have a protective effect when taking the amount which can be safely metabolized, which has been shown in other studies.
Genetic testing is now readily available either at Genova Diagnostics www.gdx.com or at www.23andme.com. The cost is around $200. Otherwise you can look at the list of symptoms for caffeine toxicity and if you have any of these it would be wise to decrease the amount of caffeinated coffee you are consuming. Here is a list from the Mayo Clinic: migraine headaches, insomnia, nervousness, irritability, restlessness, frequent urination or inability to control urination, stomach aches, and fast and or irregular heartbeat. I am sure there are probably more that could be added to the list. Caffeine is an excellent example of the fact that one size does not fit all, and pretty much everything is a question of balance.
One common symptom is increased urination. One reason this occurs is that the caffeine passes through the liver without being metabolized. It goes to the pituitary gland in the brain and stops production of anti-diuretic hormone which goes to the kidneys and opens a floodgate of urine which looks like pure water. If you don’t replace it with drinking pure water you can become total body dehydrated which is a serious problem. Alcohol does the same thing. So be sure to keep plenty filtered water on hand to prevent dehydration.
