Westend61/Westend61/GettyImages

As far as supplements go, whey protein has been enjoying its 15 minutes of fame for, well, way longer than 15 minutes. Since whey is a natural by-product of milk, so you can get it in a range of foods if you don't like your protein in powdered form.

Protein is a vital micronutrient for everybody (not just hard-training types) because it's a key player in pretty much every bodily function: digestion, tissue repair, hormone development, immunity...the list is endless. When broken down into essential amino acids, protein gives us the energy you need to live (and to train hard, if that's your thing). How much protein you need depends on your age, body composition, and activity level, but as a general guide, aim for 0.4 grams of protein per pound of body weight. In other words, if you weigh 140 pounds you need about 56 grams of protein each day.

Health benefits of whey

Whey protein is believed to come with a whole host of health benefits, such as lowering cholesterol, improving the immune response in kids with asthma, reducing blood pressure, and preserving lean muscle. (Of course, if you have a milk allergy, whey is not your friend. You gotta know what to steer clear of — get reading those labels!)

Foods with whey protein

As a popular food additive, whey lurks in some unexpected places: breakfast cereals, cake mixes, waffles, pancakes, chocolate candies, nougat, baked goods, and even meat and deli products, such as hot dogs, sausage, pate, and shellfish. But to to take advantage of whey's health-boosting benefits without any of the not-so-good effects of packaged foods, look for it in the dairy aisle.

Milk

Whey is basically the watery leftovers after milk has been curdled and strained, which happens when cheese is made. (Sounds appetizing, we know.) Cow's milk is 82 percent casein and 18 percent whey protein. They're both "complete" proteins, meaning they contain all nine essential amino acids, which are necessary for your body's growth and repair. One 240-milliliter cup of whole fat cow's milk contains 7.99 grams of protein.

Butter

Butter, which is made of the fat in milk (separated from other parts, like protein and carbs), contains approximately 0.85 grams of protein per 100 grams. But you'll get far more protein from other dairy products, so don't rely on butter to meet all your whey needs — remember, while generally healthy, butter is high in calories and saturated fats, so it's best eaten in moderation.

Yogurt

Like all milk products, yogurt naturally contains some whey protein. Plain yogurt made from whole milk contains around 3.41 grams of protein per 100 grams, but you'll get over double the protein power (and therefore more whey) from Greek yogurt: around 8 grams per 100 grams.

Cheese

All cheeses naturally contain some amount of whey protein due to the manufacturing process, but ricotta cheese is the clear winner, with 100 grams providing 7.54 grams of protein. FYI, ricotta is Italian for "recooked," because it is made by "cooking" whey that is produced when the curds are separated for cheese.

What about protein powder?

If you’re not big on dairy, the easiest way to boost your whey intake is with a supplement. Don’t worry — you can do this without having to stomach any nasty additives or artificial sweeteners. When concentrated and isolated from the other compounds in milk, whey protein can be used to make powder supplements, which you can add to your fruit or veggie smoothies. Whey is the most common protein used to make protein powders, because it's water-soluble.

When looking for a whey protein powder, go for the grass-fed variety, with as few ingredients as possible. Steer clear of anything with dextrin or glucose, which can bump up glycemic load and might make you store more fat. And avoid artificial sweeteners like aspartamine, sucralose, splenda, and saccharin. Something like Natural Force Organic Whey Protein, which is certified organic, gluten- and soy-free, and sweetened naturally with stevia leaf, is a good option. (Tip: improve the flavor by adding frozen berries, your choice of nut milk, and plenty of ice.)

About the Author

Claire Gillespie

Claire Gillespie, who has been writing and editing for 18 years, has written about health and wellness for private clients and various websites, including Women's Health, mindbodygreen, HealthCentral, Reader's Digest and SELF.