Can Energy Drinks Really Boost My Energy?

from Katherine Zeratsky, R.D., L.D.

Energy drinks may give you a temporary energy boost. However, this "boost" — which may last as long as a few hours — typically results from the large amount of sugar and caffeine these drinks contain. (Sugar-free versions of many energy drinks still contain large amounts of caffeine.)

Although the various sugars used to sweeten energy drinks can briefly increase energy, consuming large quantities of sugar is likely to cause weight gain. Caffeine is a stimulant, which also can temporarily perk you up. But too much caffeine can cause adverse side effects, such as nervousness, irritability, increased blood pressure and insomnia. Caffeine can also make your heart beat faster and trigger abnormal heart rhythms, which is especially dangerous if you have any type of heart disease.

If you're consuming energy drinks because you're frequently tired or run-down, consider a better — and healthier — way to boost your energy. Get adequate sleep, exercise regularly and eat a healthy diet. These strategies not only will increase your energy in the short run, but also will help you maintain your overall physical and mental fitness in the long run.

source: http://www.mayoclinic.com/health/energy-drinks/AN01303