Don’t fall for hype around energy drinks, summer heat

By Genevieve E. Smith, Defense Centers for Public Health-AberdeenAugust 7, 2023

Don't fall for hype around energy drinks, summer heat
The Centers for Disease Control and Prevention and the National Institute for Occupational Safety and Health suggest that water should be the first-line option for maintaining hydration before, during and after working in hot conditions. The Department of Defense Nutrition Committee also recommends avoiding energy drinks before, during or after workouts and 6 hours before sleep. (Defense Centers for Public Health-Aberdeen graphic illustration by Steven Basso) (Photo Credit: Courtesy) VIEW ORIGINAL

ABERDEEN PROVING GROUND, Md. – We’ve all heard the advice for working outdoors in summer heat: apply sunscreen; wear protective clothing; protect your eyes; drink fluids to hydrate well and often. In fact, the Centers for Disease Control and Prevention and the National Institute for Occupational Safety and Health suggest drinking 8 ounces of fluid every 15 to 20 minutes when working in the heat, as drinking in shorter intervals works better to maintain hydration than larger amounts consumed less frequently. But did you know what you hydrate with is just as important as when and how often you hydrate?

While water is generally advised for hydration in the summer heat, the lure of energy drinks is undeniable: most of them taste good, they are marketed as having various supposedly “health-promoting” ingredients, and who doesn’t love a good jolt of caffeine, especially before—or even during—a tough day of work in the heat? At first glance, these traits seem like they might make energy drinks a great hydration choice for hardworking Service members during the summer, right?

Not so fast!

Numerous factors make energy drinks the poorest choice for hydration in the summer heat. Here are a few important facts you might want to consider the next time you are tempted to choose an energy drink instead of a glass of water this summer:

1. The Department of Defense Nutrition Committee’s official position statement on the use of energy drinks recommends avoiding energy drinks or shots immediately before, during or after strenuous activities and within 6 hours before sleep.

Research on the safety of energy drinks and the various combinations of additional ingredients they contain is lacking, which means that Service members should exercise caution when choosing to consume energy drinks. Importantly, depending on your military branch and military occupational specialty, or MOS, consuming energy drinks may be prohibited and could even place you at risk of being disqualified from your regular duties.

“The U.S. Food and Drug Administration recommended healthy adults should consume no more than 400 mg of caffeine a day (about four cups of coffee),” said Joanna Reagan, Public Health nutritionist at Defense Centers for Public Health – Aberdeen. “Anything over that amount could cause serious problems in adults and certainly [in] children and adolescents. Many energy drinks contain over 200 mg of caffeine per container, which can be a risk.”

2. The caffeine in energy drinks can actually do the opposite of hydrating you.

Caffeine can be a beneficial workout aid, as noted in the May 2022 Sports Medicine journal, but it can also be dehydrating when consumed in large amounts. This issue was covered in academic articles in the 2014 Nutrition Reviews journal and the 2006 clinical trial published in the Amino Acids journal. This information is important when you consider that many energy drinks contain more caffeine than your typical cup of coffee or tea and could spell trouble for Service members working hard and sweating hard in the summer heat.

“Given the tremendous amount of heat that must be [released] during exercise through sweat…, trainees and Soldiers have no reasonable alternative for maintaining performance other than to pursue strategies that can sustain their hydration… Failure to do so may result in heat illness,” said Army Lt. Col. Brenda Bustillos, U.S. Army Training and Doctrine Command dietitian.

This means that thoughtfully choosing to drink fluids most effective at providing hydration is vital to preventing heat illness, especially in hot outdoor temperatures. For this reason, the CDC and NIOSH suggest that water should be the first-line option for maintaining hydration before, during and after working in hot conditions.

3.  Consuming energy drinks can result in various adverse reactions, including increased heart rate and blood pressure, which can increase your risk for heat illness.

Army Maj. David Yun, Disease Epidemiology Branch Chief at DCPH-A, agrees that consuming energy drinks can present a risk before or during exercise.

“Staying well-hydrated is key to preventing heat injury, and water is the best source of hydration,” said Yun. “Energy drinks should be avoided especially before, during or immediately after strenuous activity as [they] can increase heat injury risk by causing dehydration and other unwanted physiologic changes such as increased heart rate.”

Most energy drinks contain “proprietary blends” of extra ingredients added in undisclosed amounts. There is little research or understanding about how these added ingredients might interact with caffeine to worsen some of the side effects associated with caffeine, including increased heart rate and/or blood pressure or increased risk of dehydration, said Reagan. These side effects can potentially increase your likelihood of suffering from heat illness. According to the research, few of these added ingredients have been shown to provide any performance benefits.

4.  Energy drinks can contain excess calories and contribute to unwanted weight gain.

Although hard-working Service members certainly need adequate fuel for strenuous activity and training, the best sources of this energy will come from a healthy diet high in fruits, vegetables, complex carbohydrates like whole grains, and even dairy products like milk and yogurt, said Reagan.

She continued, “As an added benefit, fruits with a high water content, like melons and grapes, can even help to further boost your hydration. Consuming energy drinks, particularly in large amounts, not only provides an excess of simple sugars but may also provide more calories than you need, which could result in unwanted weight gain.”

5.  Energy drinks and alcohol can be a dangerous combination, especially in the summer heat.

Bustillos advises that consuming alcohol increases the amount of fluid you lose by increasing urination. This can delay full rehydration, especially on hot days or after strenuous activity in the heat. She suggests that Service members, “plan to stay hydrated if [they] want to enjoy adult beverages during [their] summer activities.” This means ensuring you drink enough water in addition to enjoying any alcoholic drinks. Additionally, mixing alcohol and energy drinks is a popular trend; however, the combined effects of caffeine and alcohol could put you at greater risk for dehydration or decreased ability to rehydrate adequately. This potentially harmful combination should be avoided, especially before or after participating in outdoor physical activity during the hot summer months.

The bottom line is that energy drinks are marketed as being a healthy alternative to water, and you may be tempted to hydrate with them in the hot summer heat.

6.  Don’t fall prey to the marketing hype.

Energy drinks should not be your summer go-to for hydration, as they usually contain large amounts of caffeine, can have numerous added ingredients whose effects may be poorly understood, and may even be banned depending on your Service branch and MOS. It’s important to weigh the benefits of caffeine for performance against the potential adverse effects of caffeine.

“We know from ample research the benefits of caffeine on performance,” said Andrea Lindsey, director of Operation Supplement Safety and senior nutrition scientist with The Consortium for Health and Military Performance, or CHAMP. “[With] energy drinks, it is important to know what you are consuming. Take a mental tally of how much caffeine you are consuming in any given 24-hour period… and avoid the use of energy drinks and shots before, during and after strenuous activity.”

Your best bet is to hydrate with water—before, during and after every outdoor activity this summer—and to fuel your body properly with healthy foods to help replenish salts and other electrolytes you might lose while sweating.

To learn more about energy drinks and the risks associated with their consumption, check out the OPSS article “Energy Drinks and Energy Shots: What’s the Problem?” for more information. To find out more about nutrition, sleep, and physical activity strategies to beat the summer heat, check out the Performance Triad website.

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