When you're trying to bulk up or trim down, supplementing your diet with protein is a crucial step. And, no doubt, one of the most convenient ways to get a protein fix is to pop in a store or order pre-made, ready-to-drink protein shakes and drinks online. But these beverages don't necessarily deserve a health halo. And they're definitely not without their pitfalls. 

First, some of these drinks have way more protein—and calories—than you need in one serving, says Mary Jane Detroyer, P.T., R.D. "The largest effective amount of protein you can absorb in one dose—to support muscle repair, maintenance, and growth—is about 20-35 grams," Detroyer says. 

Research backs up her stance. Scientists have discovered a ceiling for your ability to use protein. For bigger guys, the numbers rise proportionately. So a 250lb guy can handle about 42g of protein in one sitting. However, that's not to say research hasn't contradicted itself again... and again. Read our story on how much protein you should get and the best time to get it. Also check out some newer research from the University of Stirling that challenges these conventions (i.e. bigger athletes need more protein and you don’t need more than ~25g of protein post-workout). It brings some new takeaways to the table, like how you need to take into account the type of workout you're doing when considering the correct amount of protein to consume.

The bottom line: To optimize your protein intake, most experts agree, spread out how much you eat throughout the day. Try to get 20-30g in every meal and snack, Detroyer says. "It's the best way to prevent muscle breakdown and support muscle growth," she concludes.

A ready-to-drink protein shake is a convenient way to get much needed macros and nutrients in your body on your walk or drive home from the gym. But not all drinks are created equal.

What to look for in a pre-made protein beverage  

When it comes to sugar… 
Zero sugar is best. Any added sugar isn’t desirable—except if it comes from fruit or dairy, says Jim White, R.D., certified exercise physiologist and owner of Jim White Fitness and Nutrition Studios in Virginia Beach. "However, if a shake has 0g sugar, you’re usually getting artificial sweeteners," he notes. This all boils down to your preference: Some people would rather have real sugar than artificial sweeteners, while others want the artificial stuff since it has far fewer calories. 

When you factor in protein…
Some drinks and shakes have 50g of protein. That's a lot—especially after everything we covered above. "Too much protein can cause urinary loss of calcium, dehydration, and a lot of people don’t realize it can increase calories and body fat just as much as the other macros," White says. "I like a shake that has 25-40g of protein."

When you look at fat…
Don't freak over fat. "If the shake has some type of oils, omega-2s, or MCTs, I’m not against it," White says. "I’m not too focused on fat, but if you have too much in your diet, then you’re going to tip over calorie-wise."

Factor in your goals and individual needs:

  • If you're trying to increase muscle mass, then a 300-calorie shake with water is a relatively low-calorie meal and a decent snack, White says. If you’re trying to lose weight, that shake can be a meal replacement. Meanwhile, a 170-calorie shake is a bit on the light side, so you’re going to use it as a snack, or pair it with other foods for a meal to get more of what you need, whether that's carbs or fat. 
  • If you’re a casual runner, you’re not going to need as much protein as a guy who’s lifting a ton.
  • If you’re a beginner, lifting a couple times a week, you also don’t need as much protein as an intense lifter who trains heavy 6 days a week.

With all this in mind, White has listed the pros and cons of the following 10 ready-to-drink beverages. We've also noted what goals are best suited to each and how best to incorporate them during the day. Bottoms up.