What Are Protein Shakes?
Protein shakes are drinks made with protein powder. They come in a variety of flavors. You can make them with protein powder that you mix with water, milk, or another liquid, or you can buy them in ready-to-drink form. One serving of most protein shakes has between 10 and 30 grams of protein, which usually comes from dairy, eggs, or plants. But they also can have other added ingredients, like sugar, artificial flavorings, vitamins, and minerals.
Healthy adults should get about 45 to 56 grams of protein a day, and most people get enough from food. But if you exercise regularly, or otherwise live an active lifestyle, you may need more, which is why some people drink protein shakes.
Athletes also drink them to help build muscle, and these shakes might help you if you just need a little extra protein, especially if you're a vegetarian or vegan.
Which Protein Shake Is Best?
Which protein shake is best for you depends on your protein needs.
The protein in powders and shakes is either animal-based or plant-based. Whey protein, which comes from cow’s milk, is one of the most common types. Its fat and protein levels vary, depending on the type of whey. If you want to lose body fat, choose a whey-based shake that's higher in protein, has fewer carbohydrates, and only a little bit of fat.
Plant-based proteins, like pea, soy, hemp, and rice, tend to have more fiber and less fat than animal-based protein powders. These are good if you’re trying to build muscle or increase your protein intake.
Since protein shakes and supplements aren’t regulated by the FDA, look for shakes that are certified by a third party like NSF International or Informed Choice, which test ingredients. And check the label for protein content and additives.
Recommended Protein Intake
How can you tell if you're getting enough protein? The following daily recommendations come from the American College of Sports Medicine and the Academy of Nutrition and Dietetics:
The average adult needs 0.8 grams of protein per kilogram of body weight, or 0.36 grams per pound. That means if you weigh 150 pounds, you should have about 54 grams per day.
- Recreational athletics: 1.1 to 1.4 grams of protein for every kilogram of body weight
- Competitive athletes: 1.2 to 1.4 grams for every kilogram of body weight
- Ultra-endurance athletes: up to 2.0 grams per kilogram of weight
- Athletes building muscle mass: 1.5 to 2.0 grams per kilogram of weight daily
If you’re an adult athlete who weighs 75 kilograms (165 pounds) and you want to build muscle mass, the most protein you would need per day is 150 grams. That sounds like a lot, but a 3-ounce hamburger patty has 22 grams of protein, a can of light tuna in water has 42 grams, and a single ounce of cheddar cheese has 7 grams.
Protein is important for young athletes too. Recommendations from the Academy of Nutrition and Dietetics for teenagers are based on pounds of body weight rather than kilograms.
- The average teen needs 0.4 to 0.5 grams of protein per pound of body weight each day.
- Teenage athletes need more – 0.5 to 0.8 grams per pound per day.
The Academy cautions, though, against teens using protein supplements. Too much protein can be hard on your kidneys and can cause dehydration. It's best for teens to get most of their protein from foods.
Types of Protein
Protein shakes use different types of protein in varying amounts. They may include:
The source of the protein and how it's purified when it's made may affect how well your body can use it.
Although it's best to get protein from foods, boosting it with whey and casein is a good choice, as long as you handle dairy well.
Soy protein is another good option. It's a plant-based protein that works as well as most animal sources of protein. Soy is also rich in nutrients.
If you prefer plant protein but can't tolerate soy, pea, and hemp protein are some newer options.
Benefits of Protein Shakes
Many people drink protein shakes right after a workout to help repair their muscles and help them grow. Here are some other possible benefits of protein shakes:
- May help with weight loss. Because protein takes a while to digest, it can help you feel full longer.
- Can help maintain muscle mass in older people. People need extra protein as they age – 0.6 gram per pound of body weight per day, or about 90 grams for a person weighing 150 pounds. It may be hard to get that much from food alone.
- Help with wound healing. If you've had an injury or are planning to have surgery, a protein shake with whey protein can help to repair your body's tissues.
- They're a fast and convenient source of protein.
Protein Shakes for Weight Loss
To lose weight, you need to burn more calories than you consume, either by eating less, exercising, or a mix of both.
Since protein helps you feel full for longer, having more of it may mean you’re likely to eat less throughout the day. It also takes more calories to burn protein than carbs, so more protein can speed up your metabolism.
For the best weight loss results, you should combine protein shakes with exercise. Protein contains amino acids that support muscle growth, and having more muscle helps you burn more calories. But don't start drinking protein shakes and keep following your usual diet without exercising. Those extra calories will have the opposite effect and cause you to gain weight.
Side Effects of Protein Shakes
When you drink them as part of a balanced diet, protein shakes can support good health. But some people may have the following side effects:
- Gas, bloating, diarrhea or cramps: If you’re lactose intolerant, some whey protein shakes may irritate your stomach. Large servings can also cause constipation and nausea. Look for nondairy shakes instead.
- Allergic reactions: An allergy to dairy-based protein can also trigger a rash, swelling, or a runny nose.
- Possible toxins: A report released by the Clean Label Project found some protein powders have heavy metals, pesticides, and other toxins, including mercury, lead, and arsenic. It’s unlikely that they have enough heavy metals to cause any serious health effects, but it’s still a good idea to drink them in moderation.
When to Drink Protein Shakes
So when should you drink protein shakes? In very specific circumstances, they can be useful. Here are some times they make the most sense:
- When you’re growing. Teens need more protein, especially to fuel their workouts, since their bodies are still growing.
- When you’re starting a workout program. If working out is new to you and you’re trying to build muscle, you’ll need more protein than normal. The same is true when you're starting a workout program that's more intense than your usual one.
- When you’re recovering from an injury. When you're injured, you need extra protein to help your body heal.
- If you’re vegetarian or vegan. A well-balanced plant-based diet can provide all the protein you need. But if you have trouble meeting your protein goals, adding protein shakes to you diet can help.