I tried 5 ways to add protein to my coffee. Egg whites were good, but the best add-in was completely undetectable.

I've used vanilla protein powder to sweeten and add protein to my coffee before, so I knew what to expect with this one. Although I've tried plant-based options, I usually go for whey because I think it blends more easily into liquids.

For this recipe, I used 8 ounces of freshly brewed espresso, a serving of Nutrisystem's Prosync sweet vanilla shake mix (15 grams of protein), ice, and a splash of maple syrup.

I really enjoyed how it tasted, and using a simple flavor like vanilla or chocolate will allow me to change up the recipe when I want to. Unfortunately, the powder did become a little gritty after a couple of minutes.

I've had some incredible Reese's-inspired lattes and love adding peanut butter to coffee-flavored protein shakes, so I was excited to try adding PB2 (a powdered peanut-butter alternative) to my coffee.

It notably has less fat and fewer calories than the spread. A 2-tablespoon serving of peanut butter has 190 calories, but the same serving of PB2 only has 45.

I brewed two espresso shots and added a serving of PB2, some 2% milk, and honey to taste.

If I were to recreate it, I'd use chocolate milk or add chocolate syrup — this recipe definitely needed more sweetener for my tastes.

Egg whites were probably the most intimidating protein-boost option.

I whipped ¼ cup of egg whites (3.6 grams of protein) and used them as a base for ¼ cup of espresso and a splash of maple-flavored oat-milk creamer.

I don't think I whipped my egg whites correctly — they weren't quite as fluffy as they should've been — which made the whole experience a little less pleasant.

But I loved the flavor of this drink, so I'd definitely try it again using a stand mixer or high-speed blender to get really fluffy whites.

I probably wouldn't have thought of it myself, but cottage cheese can be a great protein addition to coffee. I blended a ¼-cup serving of low-fat cottage cheese with a cup of caramel-flavored coffee and a dash of oat milk.

The drink tasted good, but the cottage cheese separated pretty quickly, which was a little unpleasant.

I probably won't use it in regular coffee again, but I'm open to adding a serving of cottage cheese to protein shakes or frozen, blended coffee beverages.

Collagen is naturally found in animals, including humans. But according to Ortiz, our collagen levels tend to diminish after 30.

Powdered collagen peptides typically have about 18 grams of protein per serving and are often flavorless. But it's important to note that collagen isn't a complete protein source because it doesn't contain all the essential amino acids our body needs. It's best to pair it with other foods and complete protein sources throughout the day.

I added two scoops of Vital Proteins unflavored collagen peptides to 6 ounces of caramel-flavored coffee and topped it off with some maple-flavored oat-milk creamer.

I used a frother to whip everything together, which gave the drink a beautiful ombré effect. Plus, I didn't notice the collagen at all as I enjoyed the cup.

I don't think it's essential to add protein to your coffee — although it's smart to pair your regular cup with a balanced snack or meal to avoid a crash. But I had fun trying the different add-ins.

Collagen powder is my new favorite way to add protein to my morning coffee because it doesn't impact the flavor or drinking experience at all.

But I'll keep using scoops of chocolate or vanilla whey protein powder when I want a sweeter cup of Joe, and I'm excited to try most of these recipes again with a few tweaks.