Claims about caffeine's potential benefits for health include, among other things, that it can help prevent type II diabetes.
Having taken care of many, many diabetics during my 22 years working on the Navajo Indian Reservation (they have a significantly higher rate of diabetes than white people do) I had serious doubts about that claim.
So I contacted James D. Lane, Ph.D., who works at the Duke University Medical Center and who has studied the effects of caffeine for some 25 years and who had previously helped me with some questions. He also feels the claim that caffeine prevents type II diabetes is wrong. Part of the problem is that the studies that have shown that coffee drinking cuts down on the chances of getting diabetes are what is called correlational observations.
What is needed is controlled experimental studies. James has done that kind of studies at his facility and kindly shared with me his reasons why he thinks the correlational studies are incorrect. It doesn't seem important to share that information here. However I will summarize the results of some experimental studies done at Duke University and other research facilities also using the controlled experimental method
A group of 41 prediabetics was given 375 milligrams of caffeine prior to a meal with carbohydrates, fat and protein. Three hours later their glucose had gone up a little and their insulin level had gone up significantly. This signified that caffeine did increase insulin resistance which would clearly not be a helpful thing for folks with prediabetes. (Family Practice News 2007)
Two studies in which caffeine was given to type 2 diabetics showed that it elevated the blood glucose level and raised the insulin levels, indicating caffeine had adverse effects rather than giving evidence that caffeine improved the control of diabetes.
Three studies in which caffeine was given to healthy young, fit persons without diabetes also showed the caffeine had an adverse effect on the glucose and insulin levels. I take these six studies as good evidence that rather than helping to prevent type 2 diabetes actually it actually proves that caffeine negatively effects how the body handles sugar metabolism.
Turning to another aspect of the caffeine industry, it has been noted that since 1977 there has been a 70 percent increase in caffeine consumption in children and adolescents. In the American Journal of Psychiatry 2003 it is pointed out the majority of cases of addiction to alcohol, cigarettes and illegal drug use start during the late teen years -- especially between the ages of 15-18. This is due to the fact that the brain regions that control impulse are not fully developed. In some young people the brain development continues into the 20s. As was pointed out previously in this series of articles on caffeine is one of the things that increase impulsivity.
And it appears to me the caffeine industry has gotten more aggressive in making caffeine available to children. It has been added to candies and gum, such as Snickers Charged Bar, which has 60 milligrams of caffeine, and Sumseeds sunflower seeds with 120 milligrams.
When our only daughter came home from school at about age 15 after taking a course in home making and asked my wife if she had taken any kind of drugs when she was pregnant with her I was very glad that my wife could say no. That included no caffeine containing beverages.
The last major item we have to deal with are the energy drinks. In the past few years there has been an increasing amount of information in medical journals about problems with EDs. According to Dr. Roland Griffiths, the main active ingredient in EDs is caffeine.
Folks in a bar who drank alcohol mixed with EDs were three times more likely to leave a bar highly intoxicated and had four times greater intention to drive upon leaving the bar compared to others in the bar who only drank alcohol. Addictive Behavior 2010
Three findings related to ED use by college students:
They were more likely to use marijuana, take sexual risks, fight, omit set belts, and take risks on a dare. White students were more apt to smoke, drink, have alcohol problems and use illicit drugs. This was not true with black students. Journal of Adolescent Medicine 2008
They were used by 22.6 percent of students in their second year in college and 36.5 percent in their third year. Those students used more alcohol, other drugs, showed higher levels of sensation seeking, use of prescription stimulants and pain relievers. Journal of Addictive Medicine 2010
In a study of 4,271 students from 10 North Carolina universities, the use of EDs was shown to increase the chance of being taken advantage sexually by about 75 percent, of taking advantage of another sexually by more than 100 percent, of being hurt or injured more than 100 percent, of riding with a driver who was under the influence of alcohol by more than 100 percent and of requiring medical attention by more than 100 percent. It also increased the use of alcohol. Academic Emergency Medicine.
And of particular concern is ED-related supraventricular tachycardia -- A 23-year-old female with no history of heart disease was brought to a hospital with an irregular heart beat and chest tightness shortly after drinking a GNC Speed Shot and a Mountain Dew. Her heart was beating at 219 beats per minute. Fortunately doctors were able to correct this. She could well have died had not medical help been readily available.
It is important for the public to understand that there is only one kind of caffeine. That is, the caffeine in coffee, tea, EDs, other sources of caffeine is all the same compound. That being the case it would only seem logical that if you drink enough green tea for instance you could get as much caffeine as in EDs. The range of caffeine is from 50 to 505 milligrams per serving. Thus it appears the same kind of behavior could be expected.
Next week, we'll wrap up with a consideration of claims about antioxidants found in caffeinated beverages.
Dr. Don Casebolt of College Place is a retired physician who is passionate about preventive medicine. He spent 4 years as a medical officer in the U.S. Navy, the last 21/2 years as a flight surgeon. He also worked on the Navajo Reservation for 22 years.