Consider risks before embracing caffeine hype

Have you heard all the buzz lately about caffeine being associated with a reduced risk or delayed onset of dementia?

A recent study published by the University of South Florida and the University of Miami monitored the memory and thinking processes of people over 65 and found that those with higher blood caffeine levels avoided the onset of Alzheimer's disease in the two to four years of study follow-up. Another study in the New England Journal of Medicine tracked the health and coffee consumption of more than 400,000 older adults for 13 years and found that coffee drinkers reduced their risk of dying from heart disease, lung disease, pneumonia, stroke, diabetes, infections and even injuries and accidents.

While these may be great "perks" for some coffee drinkers, there are a few things you should know before you start stocking up on caffeine. In nearly all of the studies, coffee appeared to be the primary, and maybe only, source of caffeine consumed. Other sources of caffeine were not considered. And studies referred only to moderate amounts of coffee -- about three cups a day. So "if a little is good, a lot is better," right? Wake up and smell the coffee.

Sodas, tea and coffee contain only moderate amounts of caffeine. However, consumption has dramatically increased with the recent hype over energy drinks. Energy drinks, which should not be confused with sports drinks, were the fastest-growing beverage in the United States in 2011. Half of these highly caffeinated drinks, sold under popular names such as Red Bull, Monster, Rockstar and Full Throttle, are sold to children, adolescents and young adults and were responsible for the 5,448 caffeine overdoses in 2007.

The average adult consumes less than 100 milligrams of caffeine per day. While less than 300 mg is considered relatively safe, amounts greater than that can contribute to some health problems, 1000 mg can be toxic and 5,000 to 10,000 mg is considered lethal. The FDA regulates a maximum of 71 mg of caffeine per 12-ounce beverage (soda, tea, coffee). Energy boosters, which are marketed not only as drinks but also as supplemental pills, gums and candy, contain caffeine in concentrated amounts intended to produce energy, but not without a price.

Caffeine can overstimulate the central nervous system. Unlike coffee, tea and sodas, the FDA cannot regulate energy drinks, which are considered a dietary supplement and not a food. That may be why the amount of caffeine in an energy drink (50 to 500 mg per can or bottle) has three to five times more caffeine than a 12-ounce can of soda.

Concentrated amounts of caffeine act as a natural diuretic and deplete nutrients by slowing absorption and flushing them out (especially water soluble vitamins and minerals). Lack of important nutrients can lead to nervousness, anxiety, irritability and even blood sugar problems (especially in diabetics, glucose intolerants, hypoglycemics, etc…).

Side effects are especially notable in people with diabetes, seizures, cardiac problems, mood/behavior disorders or those taking certain medications. Heavy caffeine consumption is associated with more serious side effects, including seizures, mania, stroke and sudden death. So while many of these conditions have been reported in children and young adults, the primary consumers of energy drinks, caution should be taken with all individuals, especially older adults with existing health conditions.

One more thing: Be aware of the danger when mixing energy drinks and alcohol. The stimulants in energy drinks can mask the depressant effects of alcohol. In other words, individuals who combine alcohol with energy drinks say they feel less drunk, but their intoxication levels are masked by the stimulant, making them more prone to drunkenness, injury and alcohol poisoning. Several studies also suggest that energy drinks can serve as a gateway to other forms of addiction or drug dependence. Lastly, the combination can also have a negative effect on the heart, including shortness of breath, rapid heartbeat and heart attacks.

So although a couple of cups of coffee might improve your ability to think better, high levels of caffeine such as those found in energy drinks or mixed with alcohol might destroy your ability to think altogether.

Anne R. Lindsay is an assistant professor and exercise physiologist at the University of Nevada Cooperative Extension. She conducts research and programming in adult fitness, physical activity, body image and childhood obesity prevention. Contact her at lindsaya@unce.unr.edu.