Protein is ideal for the repair and growth of your muscles. So whether you’re focused on building muscle or losing weight, protein shakes can help supplement your diet and achieve your wellness goals.
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While how much protein you need to consume varies based on your goals, the recommended daily allowance (RDA) is 0.8 grams per kilogram of body weight or about 20 grams per meal. If you’re looking to build muscle you may need to up that amount by almost double.
But there are different beliefs on when to drink a protein shake: pre-workout or post-workout?
Registered dietitian Kate Patton, MEd, RD, CCSD, LD, explains why timing matters and what to consider when using protein shakes.
Why timing matters
Your body is primed after a workout to use any protein you consume. It comes down to understanding your body’s metabolism and knowing whether your body is in a catabolic or anabolic state.
If your body is in a catabolic state, this is when it’s breaking down your muscles. Your body will be in this state while you’re exercising or working out.
And then when your body is in an anabolic state — or post-workout — your body is rebuilding and refueling.
“That window of time after you exercise is when your body is just a little bit more efficient at utilizing that protein to help build that muscle, versus while you’re exercising and you’re breaking down the muscle and stressing the muscle.”
It’s key to get enough protein after exercising to help repair your muscles, which are worn down.
“And if you’re trying to build muscle, then you need that protein to help you,” explains Patton. “The building blocks of our cells are amino acids and we get amino acids from protein.”
Should you drink a protein shake before or after a workout?
While there’s a lot of debates on the best time to drink your protein shake, Patton recommends that you drink it after your workout.
“You’re going to get the most bang for your buck,” she says. “Your body is going to utilize more of that protein. It’s fast and easy to consume so it gets into your body to really help you recover and refuel.”
Ideally, you want to consume your protein shake within an hour after exercise.
When to drink for weight loss
If you’re looking to lose weight, you still want to drink your protein shake after your workout.
“The benefit of the protein shake is that it takes longer to digest so it tends to keep you feeling full,” says Patton. “If you’re trying to lose weight, your body is going to use that protein efficacy to preserve your muscle and break down body fat instead for energy.”
Can you drink a shake on an empty stomach?
In most cases, drinking a protein shake on an empty stomach won’t cause you any harm.
“If it’s a tough workout, try hydrating with water during the workout first and then drink the protein shake after,” says Patton.
If you’re lactose-intolerant, you will want to pay attention to the amount of lactose that may be added to shakes and powders before you consume.
“Protein shakes that are specially formulated more for weight loss are low in carbs,” says Patton. “Those may have what are called sugar alcohols and those can potentially cause bloating and gas. Be sure to read the ingredient list.”
Are protein shakes healthy?
Yes, a protein shake can be a great option to replace a snack between your meals and to drink after a workout.
There are different forms of protein shakes. Here are a few examples:
- whey protein. “If you’re lactose-intolerant, there’s a form of whey protein called whey protein isolate,” says Patton. “The isolate is almost 100% lactose-free so it’s really tolerable for people with a lactose intolerance.”
- Soy protein. Patton says this is a good choice to use if you’re vegan because it’s a complete protein, meaning it has all the essential amino acids.
- Pea protein. You may want to opt for a plant-based version like pea protein if you’re vegan or vegetarian.
- Hemp protein. Another plant-based version, this one is also great for vegans and vegetarians.
Protein shakes, as with any other dietary supplement, aren’t regulated by the Food and Drug Administration. So Patton says it’s important to make sure whatever protein shake you use is clean and safe. There are a few third-party companies like NSF International and Informed Choice that test ingredients.
“Some protein shakes use a proprietary blend and the manufacturer doesn’t list what the ingredients are,” says Patton. “I would avoid any brand that uses the phrase ‘proprietary blend.’”
Whatever your goals, it’s best to focus on the amount of protein you need each day. You want to space out your protein intake throughout the day for maximum results — and adding a protein shake to your routine post-workout can be a good way to reach that target.