High-protein diets are one of the latest food trends.
Protein is being added to snacks and drinks. Social media influencers are encouraging people to eat more protein every day. But how much protein do we really need?
We asked Joanne Slavin, professor of food sciences and nutrition at the University of Minnesota Twin Cities, about how much protein an average person needs to eat, what foods contain protein, and why food trends like this one come and go.
6 questions with Joanne Slavin
What is protein?
“Protein is a nutrient we need to get, and it’s also a calorie source. So we have a recommended amount of protein to get every day, and if we don’t have it, we can’t grow. So it’s particularly important during growth and development. Protein is the most important nutrient we need to get.”
Why do you think our current discussion in America and debate over protein and how much is such a thing right now?
“All of a sudden, you see all these people dumping protein into everything, and it’s usually the people that least need it. It’s frustrating that right now, people are just saying, ‘Hey, more protein. More protein.’ We’re putting it in snacks. We’re putting it everywhere. Like you say, people are dumping it everywhere.
“In general, the average person in the U.S. is not protein-deficient, but it’s incredibly important to get it. So I never wanna discount that. Make sure the people that need it are getting it throughout the day, and make sure it’s the highest quality protein we can get to them.
The National Academies of Science says people need 0.8 grams of protein per kilogram, 0.36 grams per pound. It varies by age, weight and lifestyle, but in everyday food terms, about how much are we talking about?
“First of all, I wanna say it’s an allowance, so it’s not a requirement. So when we figure out recommendations, we are going kind of high to make sure everybody gets it. So our reference person, who’s our 70-kilogram person or 154 pounds, we look at their needs as 56 grams of protein for the average person.
“If you were eating a packaged food, you could look at that number, but to give you some idea, a dairy serving has eight grams of protein. One ounce of meat, fish, or an egg has 7 grams of protein. So those are your biggies. If you look at an ounce of meat, people that would eat 12 ounces, like you’re way past it.
“But a lot of the other foods we eat don’t have any, so obviously, fruit has no protein. Oils have no protein. Vegetables have about 2 grams of protein per serving. And the starch group or rice, bread would have 3. So putting that all together, 56 can be a really, you know, a lot to get to if somebody isn’t eating a lot of protein foods and we want to get it throughout the day.”
“Moderation and variety is a key to good nutrition. So if people are eating the appropriate serving sizes, we would have no problem getting to that 56 grams a day. Generally, what’s concerning is that when new trends come, people assume that what they were taught as a kid is wrong. So every culture has figured out how to put high-quality protein into their diet and also to combine proteins.
“So when we look at incomplete versus complete, and people are like, ‘What is that?’ We’re an animal, so that anytime we’re eating an animal product that is going to be high-quality protein, the amino acid profile is going to be pretty much what we need, and it’s going to be very digestible. But if you put together like a peanut butter sandwich, peanut butter and bread; rice and beans; tortillas, beans — all cultures have figured out how to put these things together and get complete proteins if you eat these complementary proteins.”
One voice in this public conversation that’s very loud is people who want to build a lot of muscle strength, weightlifters. They may have more protein needs, but if you eat too much, what is the risk?
“I just want to mention too, the bodybuilders do know the most about it, but even the studies that have been done, do they even need more than 0.8 [grams]? Generally, they don’t, but you know, they tend to eat a lot more than that. The risk is gaining fat. Obviously, it’s extra calories, but then the concern is if you’re just, all of that protein, you have to get rid of the nitrogen; it has to go out in urine as urea. So your kidneys are working.
“It’s really clear as soon as you have kidney disease, you have to limit protein. So my dietitian side says, ‘Hey, there is no reason to overdo it.’ Because first of all, there’s extra calories and it’s another source of pressure on your kidneys to get all of that out. It’s wasteful both on the environmental side, the cost side, and your health side. There’s really no upside to it.”
People often quote Michael Pollan, the author of “The Omnivore’s Dilemma” and several other books. He famously said, “Eat food, not too much, mostly plants.” Do you find it a useful way to think broadly about diet, including protein?
“I think it is just because there’s so much overconsumption in the U.S., right? And you can get these nutrients from plants. Plants tend to be less expensive. But as far as protein, if you’re gonna eat a tiny amount of food, it’s hard to get it from plants without isolating it. So the processing, you know, there’s just been a lot of controversy on processing.
“But to get a lot of protein into a protein powder is gonna take a lot of processing. So. I grew up on a farm. I still own it. I think people need to be connected to their food, so I completely agree with that, that if you know what your food is and you have some care in producing it and some care in eating it, we’re all gonna be better off rather than obsessing about one particular nutrient and say, this is the be all or this is the enemy of the week.
“So having that focus on overall enjoying our food. It’s enjoyable. There’s nothing wrong with enjoying our food. We just don’t need as much of it as most of us eat. So very good advice. And it goes back to the original advice from [U.S. Department of Agriculture], moderation and variety, variety of foods enjoyed with your family. Can’t go wrong.”
How do you think about why these food trends keep coming around?
“I kind of think people believe that food is like a drug, and there’s like a missing thing. So once we get it, then voila, it’s solved, and it will never happen. And it’s kind of hard. As a dietitian and nutritionist, we want to make it more scientific and kind of say exactly what’s the [recommended dietary allowance] and we have to do that. We have our best data of how much nutrients you need, and we have the foods to get you to those nutrients. But I don’t want everybody just thinking they can pop a pill and as long as they have those nutrients, they’re going to be happy, healthy, and wonderful.
“No, it’s just never that easy and it just cycles. It’s amazing. The longer you stay in the business, is like, ‘Well, how long is the life cycle of one of these trends?’ And they just come and go. And just like with every question we get into in nutrition, there’s risk and benefit. We have to balance that and make sure people can get their food supply and have enough food for all of us to live by.”
This interview was edited for clarity.
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Julia Corcoran produced and edited this segment for broadcast with Todd Mundt. Allison Hagan produced it for the web.
This article was originally published on WBUR.org.
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