The Best and Worst Energy Drinks

Take a stroll through a college library during final exam week and what do you see? Most often, it's sleep-deprived students battling endless pages of notes. And what's powering their all-nighters? A giant energy drink can.

While college library vending machines are often stocked with a variety of energy drinks, they aren't the only consumers. After all, it's hard to find a CVS or Walgreens without a Red Bull fridge at checkout. Although energy drinks are convenient and quick, are the energizing benefits worth the cost of the ingredient list? Next time you need a boost, consider these healthier energy drink alternatives.

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While energy drink ingredients can vary from brand to brand, the primary ingredients within each can are often the same.

Caffeine is a stimulant that affects the body's central nervous system for up to six hours after consumption, according to the University of Michigan Health Service. Often, these effects include increased clarity and alertness but also increased heart rate, body temperature, blood pressure and blood sugar levels, among others. Caffeine is one of the primary components of energy drinks and can cause dependency over time, according to the World Health Organization. While a cup of coffee contains about 94 milligrams of caffeine, according to the USDA, energy drinks often contain about 74 milligrams per 8 ounces (a common serving size). For a frame of reference, up to 400 milligrams of caffeine per day is safe for the average adult, according to the Mayo Clinic.

Added sugar is another primary ingredient in most energy beverages. According to the American Heart Association, the recommendation for daily sugar intake is no more than six teaspoons or 25 grams for women and nine teaspoons or 38 grams for men. However, the average American consumes about 17 teaspoons of sugar each day, which translates to 57 pounds of added sugar consumed each year per person, according to the University of California San Francisco. Energy drinks are a big culprit behind overconsumption of sugar, as they often contain about 30 grams, according to the USDA.

Read More: Recommended Daily Allowance of Sugar

Taurine is one of the lesser-known but common ingredients in energy drinks. An amino acid, taurine is vital in several of the body's metabolic processes, according to the Mayo Clinic. Naturally found in meat, fish and dairy products, taurine can also be consumed as a supplement or additive. According to a 2017 study published in Birth Defects Research, the body's taurine levels naturally increase after stress is perceived. After testing the impact of caffeine, taurine and energy drinks on mice, the study found that consumption of these substances in energy drinks may not actually benefit mental performance.

Initially used in South America to increase energy, guarana seeds contain more caffeine than any other plant, according to an article published in Mayo Clinic Proceedings. Although guarana is commonly used in energy drinks, herbs and supplements are not regulated by the Food and Drug Administration (FDA) as strictly as medications and, therefore, claims regarding guarana have not been verified. According to the American College of Cardiology, possible side effects of guarana consumption include anxiety, heartburn, irregular heartbeats, sleeplessness and headache.

• Increased energy due to caffeine and sugar content
• May help improve attention or mental clarity
• Convenient and hassle-free
• Preferred alternative for those who don't like coffee taste

• Can lead to weight gain and/or increased levels of obesity due to high levels of added sugar and calories
• May contribute to caffeine dependency
• May lead to cardiovascular issues due to increased heart rate
• May trigger feelings of anxiety, irritability and jitters due to caffeine content

• ​Water -​ Before you reach for an energy drink, make sure your dip in energy doesn't stem from inadequate hydration. Most people need about six to eight glasses of water each day, according to the American Academy of Family Physicians, and getting less than that may make you feel sluggish. The easiest way to check your hydration is to take a peek into the toilet bowl next time you pee. Dark yellow urine is often a clear sign of dehydration. On the other hand, if your urine is colorless or light yellow, you're getting enough water.
• ​Black Tea and Green Tea -​ Black and green tea have less caffeine than coffee (about 20 to 45 milligrams per cup) and are associated with an array of health advantages, according to Harvard Health Publishing. Tea, when consumed without added sugar or other ingredients, is often linked to heart and blood vessel benefits. The flavonoids (a plant compound) in tea help bring down inflammation and may reduce arterial plaque buildup.
• ​Coffee and Espresso -​ While coffee and espresso do contain caffeine (there are 62 milligrams of caffeine in a shot of espresso), there are also other benefits behind coffee consumption. Recent research suggests that moderate coffee consumption (three to four cups per day) may be linked with longer lifespans, according to Harvard Health. Other research has found that coffee drinkers may have reduced risk of cardiovascular disease and type 2 diabetes.

• ​Red Bull -​ One 12-ounce can of Red Bull contains 111 milligrams of caffeine and 38 grams of sugar, according to the USDA, which is more than the daily sugar dose for women and as much as men should have in a day. Red Bull also contains taurine and 159 calories per can.
• ​Monster Energy​ - One serving of Monster Energy (about 8 ounces) contains about 113 calories, according to the USDA. However, it's important to remember that a can of Monster Energy — which is typically the amount people consume — actually contains two servings. One serving also contains 26 grams of sugar and 79 grams of caffeine.
• ​Rockstar Energy Drink -​ One 16-ounce can of Rockstar Energy Drink contains about 278 calories, according to the USDA. Each can also contains 59 grams of sugar and about 158 grams of caffeine.
• ​5-Hour Energy -​ Technically a supplement, 5-Hour Energy comes in small doses but packs a punch. It's formulated with taurine and contains a comparable amount of caffeine to a cup of coffee, according to the company's website. Although further research is needed, combining taurine with caffeine may cause unwanted side effects like increased blood pressure, interrupted sleep and anxiety, according to the Mayo Clinic.

​Energy Drinks and Alcohol​

It's a good idea to skip the Red Bull and vodka. Energy drinks are often mixed with alcohol, although it is not their intended use. According to the above 2017 study, mixing alcohol and energy drinks raises serious concerns. This mixture actually increases the abuse potential of alcohol, the researchers note, and has been associated with elevated rates of binge drinking.

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