When Does Coffee Become an Energy Drink? Science Behind Starbucks Doubleshot

As a biochemist who researches energy drinks, I get asked all the time why people need energy drinks and why people can’t just drink coffee instead. There’s no easy way to answer these questions, but it helps if we look at the products which blur the lines between “coffee” and “energy drink”.

For this Energy Drink of the Month review, we’ll examine the science behind Starbucks Doubleshot Energy, an “Energy Coffee Beverage”.

  • How does this compare to other energy drinks?

  • Is it safe to drink?

Starbucks Doubleshot Energy Drink
Highlighting some choice words on the Starbucks product page [Souce: http://doubleshot.com/drinks.html#coffee]

How does this compare to other energy drinks?

The Stereotypical Energy Drink

When you hear a news story about someone hospitalized after energy drink consumption, what brands do you picture? 

There is no legal definition of the term “energy drink”. Before we compare this “Energy Coffee Beverage” to similar coffee-energy hybrids, let’s start by comparing it to the energy drink stereotypes created by “The Big Three”, Red Bull, Monster, and Rockstar:

√ Caffeine

√ Sugar

√ B-Vitamins

√ Guarana

√ Ginseng

√ Taurine

X Carnitine

X Glucuronolactone

Starbucks Doubleshot Energy has almost as much caffeine as the original Monster and Rockstar (146 mg per can compared to 160 mg in Monster and Rockstar Original).

Sugar content is not a fair comparison because both Monster and Rockstar offer low-Cal and no-Cal options. If we only look at the original products, Starbucks Doubleshot Energy has half the sugar as its energy drink forefathers (26 g per can compared to 54 g Monster Original; 60 g Rockstar Original).

Red Bull does not have Guarana nor Ginseng, but these two ingredients are included in Doubleshot Energy as well as the Energy Blends in both Monster and Rockstar.

There are some pretty gross myths about the origins of taurine and Red Bull, but (A) taurine DOES NOT come from bull sperm and (B) taurine is included in Red Bull, Monster, and Rockstar. Oh, and also Doubleshot Energy.

THAT’S RIGHT! This “Energy Coffee Beverage” has almost all the typical ingredients of a stereotypical energy drink! Surprised? 

But wait, the caffeine comes from coffee (and guarana), so doesn’t that make it different/better/safer than an energy drink?


Similar Energy Drink – Coffee Hybrids

When it comes to the “dangers of energy drinks”, we have to be careful about what kind of exceptions we make for coffee beverages. As a society, we don’t seem as alarmed when someone has multiple cups (or a whole pot) of coffee. The assumption is the caffeine content is not dangerous since it’s coming from a natural source.

If we assume coffee is safer than energy drinks and we’re willing to overlook the caffeine content, does that mean we condone these three coffee-energy hybrids?



  • All three have caffeine from coffee and guarana.

  • All three have taurine, B-vitamins, sugar, guarana, and ginseng.

Ingredient-wise, they are not significantly different. The biggest distinction is that one of them is made by a brand known for its coffee, and the other two are energy drink brands. If that is all that separates them, how can we criticize one but not the other?

In my opinion, we need to warn those under age 18 about all three.
All three have too much caffeine for a minor [Ref: American Academy of Pediatrics].

Biochemically, caffeine does not affect the body differently when it comes from a natural source versus a synthetic source. The caffeine limits for adults and for those under age 18 do not change based on where the caffeine comes from.  [Ref: EFSA]

“But don’t the ingredient interactions make energy drinks more dangerous?” (No)

“But aren’t energy drinks more dangerous for heart arrhythmias than plain caffeine?” (No)

⇒ Visit this article for The Ultimate Guide to Energy Drink Ingredient Interactions, plus What Science Tells Us about Coffee Versus Energy Drinks for Heart Arrhythmias


Is it safe to drink Starbucks Doubleshot Energy?

If you are trying to abide by the American Heart Association’s recommendations to limit sugar intake to 9 teaspoons/36 grams for men and 6 teaspoons/25 grams for women per day then this may not be the drink for you. (Of course, you could always drink half the can and share or save the rest for later…)

If you are sensitive to caffeine, you should not consume this drink.

If you regularly consume a Grande cup of plain black coffee (330 mg caffeine according to Caffeine Informer), then you should have no concerns about consuming this drink.

Whatever your opinion of stereotypical energy drinks, Starbucks Doubleshot Energy proves that #NotAllEnergyDrinks deserve our fears and criticism.



I’ve researched the science and safety behind energy drinks and their ingredients since 2003. This book is the culmination of my research:

Explore the CAFFEINE INFORMER database

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