Despite the intense advertising hype, “energy drinks” won’t solve the problem of the afternoon fade many people experience, nor will they boost an athlete’s performance, say local registered dietitians.

In fact, these drinks marketed to competing and recreational athletes and people with demanding work and school schedules may actually worsen fatigue and cause harmful side effects, they say.

Most energy drinks, such as Red Bull and Venom, contain 75 to 85 mg of caffeine, which is a central nervous system stimulant. Newer products such as Rock Star Energy Shots are ratcheted up to 200 mg of caffeine, while extreme products such as FIXX have 500 mg of caffeine in a 20-ounce serving, says Vanessa Provins, RD and clinical dietitian at Porter Hospital in Valparaiso. That’s equivalent to five cups, or 40 ounces of strong, brewed coffee. This high caffeine level has the potential to cause caffeine intoxication characterized by such symptoms as heart palpitations and irregular heartbeats, constant fatigue, hyperactivity, irritability and facial flushing.

The source of the caffeine is another concern, Provins says. Many energy drinks get their caffeine from herbal extracts. One of the most common is guarana, the seed of a rain forest plant that has such common side effects as anxiety, diarrhea, headache, increased urination, nausea, tremors and vomiting. Severe side effects include difficulty breathing, agitation, irregular heartbeat and seizures.

“Caffeine is a diuretic, which means it dehydrates the body,” says Beth Stritar, RD and clinical dietitian at St. Margaret Mercy Hospital in Dyer. That afternoon fatigue so many people experience may actually be caused by dehydration, Stritar says. Consuming energy drinks may make this problem worse when the “crash” comes, she says.

Many youth, college and professional sports leagues now ban the consumption of energy drinks prior to practice or a game because of the potential for harm, Stritar says. “Energy drinks can cause high blood pressure as well as dehydration,” she says, adding that some heart-related problems experienced by athletes during practice or a game could be related to high caffeine consumption.

Because staying hydrated is important for everyone, water is still among the best “energy drinks,” Stritar says.

The human body requires water to function, making water an important nutrient, Stritar says. For example, water composes 75 percent of our muscles, 80 to 90 percent of our hearts and 75 percent of our brains. Water also helps remove toxins from the body and aids in building and repairing muscles.

Dehydration can become a serious problem, Stritar says. Being 2 percent dehydrated can seriously degrade physical and mental functions, while being 15 percent dehydrated is likely to be lethal. The average adult needs to replace about 80 ounces of water lost every day through perspiration, the kidney/bladder system, bowel movements and respiratory system.

Getting the necessary water sometimes means planning ahead, Stritar says. “Bring along a bottle of water when you’re out shopping or at an activity,” she advises.

Fruit juices, made with 100 percent fruit, and fruit smoothies made with yogurt are other good choices to stay hydrated and get a boost of energy, Stritar says. Fruit provides antioxidants, while the yogurt in a fruit smoothie supplies protein. By making your own smoothies, you can control what you consume, she advises. “During the summer, I freeze blueberries to make smoothies. You can use any frozen fruit,” Stritar says.

Other good alternatives are green tea and white tea, which give a modest caffeine boost without making you jittery, she says. Even a piece of fresh fruit will supply needed hydration and carbohydrates for energy, Stritar says.

Beverages have made their mark as fluid-replacement for athletes, Provins says. The first and most successful sports beverage is Gatorade, which was developed in 1965 by four researchers at the University of Florida, where sports teams are called the Gators. This pioneer in sports beverages provided athletes with liquid nutrients lost during sweating—primarily glucose, water, sodium, chloride and potassium, she says.

Today, pre-portioned liquid nutrition, including meal replacement products such as Ensure, are making their way into the sports and exercise arena, Provins says. Originally designed to aid the recovery of the elderly and seriously ill patients, these products are becoming popular among athletes because they provide high carbohydrate levels and are easy to consume before, during and after exercise, she says.

Yet, Provins says, not everyone, not every athlete needs sports beverages for hydration or energy. “While sports beverages enjoy great popularity, water is still an appropriate beverage in many circumstances,” Provins says. For example, most athletes who exercise for less than 45 minutes don’t require carbohydrate-containing beverages, she says.

Water-based beverages are also being marketed to boost energy and replace fluids. Vitamin waters, for example, are fortified with various vitamins and some contain protein, Provins said. But, they also often have high sugar levels, increasing the calorie count. Flavored waters are also popular among those who don’t like plain water. Natural and artificial flavors and sweeteners are part of the mix. Some also contain herbal extracts. “Read the label to know what you’re drinking,” Stritar says.