You're Probably Not Eating Enough Protein

In the ongoing convo around the best eating routine for health goals, one of the OG macronutrients—and where we get it—is undergoing a rethink. Listen up: Experts are (loudly) singing protein's praises. If you have ever wondered, "how much protein do I need?" or questioned what the *best* protein sources are, read on!

[table-of-contents] stripped

When Carrie Forrest’s Steak with Gorgonzola sauce was set down on the white tablecloth late in the spring of 2014, she began looking around the restaurant nervously. She wasn’t famous, or at least not exactly: She had a vegan blog with an app successful enough that she’d just flown from her home in Pismo Beach, California, to present at a food blogging conference in Miami, before flying up to New York.

Forrest—who has a master’s degree in nutrition—ate plenty of beans and soy for protein, yet she was exhausted. In fact, she’d been low-energy for months, maybe ever since she’d switched to being vegan in 2010, inspired by Alicia Silverstone, a love of animals, and a hope that maybe she would feel better and lose the stubborn five pounds that kept coming back. Giving up meat was easy; it was yogurt that had been hard, but lately she’d started looking longingly at eggs in farmers’ markets. In New York, though, something clicked.

“I was just like: This isn’t working,” Forrest, now 47, says of being vegan. “I felt ashamed. But I also felt like: This is my health and I have to make a change.” She doesn’t remember much about the steak except that it was delicious and also that she couldn’t finish it. The next morning, she woke up and went right back to it, eating the leftovers cold, directly out of the fridge.

Almost immediately, she began searching for the words for her audience, and after revising more than half a dozen times, on June 14, 2014, she hit publish on “Why I Am No Longer Vegan,” which included an apology if the headline caused “disappointment, confusion, or anger.” She held her breath.

Within hours, she had hundreds of negative comments (“No true vegan would ever ‘listen to their body’ and eat animal products,” wrote one) and bad reviews of her app on the app store. So many people unsubscribed from her email list that she received an auto email from Mailchimp saying her account had been suspended because the company was afraid she’d been hacked. Forrest’s close friends, also vegan, deserted her.

“I was pretty alone, except for my husband and my therapist,” she says. But she held on, eating farm-raised beef, adding chicken to her stir-fry, and feeling her energy levels stabilize. It wasn’t until about two years later that the first email came from a negative commenter saying she, too, had had to give up being vegan and apologizing for being so hard on Forrest. The emails began as a trickle, then turned into a small but steady stream, inspiring Forrest to publish a post that remains one of her most popular. Its title: “How to Reintroduce Meat After Being Vegan or Vegetarian.”

Meet the experts: Carrie Forrest MBA, MPH, is a blogger, cookbook author and creator of Clean Eating Kitchen. Sareen Gropper, PhD, RDN, is a professor of nutrition at Florida Atlantic University. Gabrielle Lyon, DO, is the founder of Muscle-Centric Medicine. Luc van Loon, PhD, is a professor of physiology of exercise and nutrition at Maastricht University Medical Centre. Carol Johnston, PhD, RD, is a professor of nutrition at Arizona State University. Neil Iyengar, MD, is a medical oncologist specializing in breast cancer at Memorial Sloan Kettering.

It's time to reframe the conversation around protein.

After at least two decades of being nudged toward everything plant-based—even McDonald’s rolled out a McPlant menu—a small but growing chorus of researchers and public health experts are pushing back a bit. It’s not that you necessarily must eat meat, but that you have to be quite vigilant to get all the protein and nutrients you need without any animal products.

“Not everyone can sustain a healthy weight, meet protein and other nutrient needs [like iron], and stay on a vegan diet,” says Sareen Gropper, PhD, RDN, a professor of nutrition at Florida Atlantic University who generally recommends the Mediterranean diet. While Gropper notes that “many people on vegan diets are healthy and meeting all their nutrient needs,” she says that vegans can be at increased risk to suffer from hair loss and general fatigue due to protein or iron deficiencies.

But first! It’s important to clarify that, yes, plants are many wonderful things, but one thing most are not is a wonderful source of high-quality protein. Because after years of being virtually shunned due to worry over too much saturated fat or too many simple carbs, protein may well be the macronutrient of the moment, and many of us aren’t getting enough of it. Or at least, of the right kinds of it at the right times.

Why is protein important?

Humans need amino acids, the building blocks of protein, to mount a response to infection, as well as for just about every structure in the body—bone, liver, gut, tissues, hair, nails, skin, and the one that likely comes to mind first when you think of protein: muscle. “But people tend to only think of muscle and protein in relation to fitness, and that’s a mistake,” says Gabrielle Lyon, DO, founder of Muscle-Centric Medicine.

Over the past 20 years, researchers have come to understand that skeletal muscles are endocrine organs, just like the thyroid. During muscle contraction, they produce and secrete small proteins, called myokines, that can keep inflammation from getting out of hand. This is also why being under-muscled is fast becoming a health problem to watch.

Clearing the Air: The belief that high-protein diets can cause kidney problems in healthy adults is being reexamined as well by certain experts. Processing large amounts of protein does not lead to a decline in kidney function, according to a Journal of Nutrition review of more than two dozen studies involving hundreds of participants. “This thought came from the fact that people with kidney failure or reduced kidney function are generally put on a low-protein diet in order to not overburden the kidneys,” says Luc van Loon, PhD. “But it’s not the other way around. There’s no evidence whatsoever.” Duly noted.

But this whole convo isn’t about how much (or little) you can deadlift; patients with less muscle mass have more complications, longer hospital stays, and lower survival rates, according to an Annals of Medicine review of nearly 150 studies. Plus, aging bodies process protein less efficiently and need more of it to maintain muscle strength, bone health, and other functions.

Start thinking of muscle as a healthy aging strategy, beyond the aesthetic aspect, suggests Dr. Lyon. One way to do that: Focus on high-quality protein, she says, which will protect you from many chronic diseases.

How much protein do you really need?

Although the RDA for protein hasn’t changed for 30 years—it’s a modest 0.36 grams per pound of total body weight, or 0.8 grams per kilogram (no wonder some people think they over-consume it!)—researchers are now saying we, particularly regular exercisers, need more like 1.2 to 1.5 grams per kilogram to support tissue growth.

For most of us, this amounts to about 30 to 35 grams per meal. And FYI: the “per meal” language is intentional; you really do need to eat it allll day. “The body doesn’t store amino acids,” says Carol Johnston, PhD, RD, a professor of nutrition at Arizona State University. That means it’s best to have them available at any time, so spread your proteins throughout the day (and make sure you have protein with breakfast).

That may seem easy enough with protein added to everything from cereal to cookies to beer (!), but here’s where things get tricky. All protein is not created equal.

What is the best type of protein for building muscles?

Proteins consist of molecules made from a sequence of amino acids, 11 of which our bodies make, and 9, called essential amino acids, that we can only get from food. In addition to being the foundation of proteins, the nine essential aminos are also signaling molecules.

Basically, when you eat them, particularly one called leucine, they start stimulating protein synthesis. All animal products contain the essential aminos; many plant proteins (except quinoa, soy, chickpeas, pistachios, buckwheat, amaranth, hemp seeds, and spirulina) are missing at least one. If you don’t eat all nine aminos, nothing happens. (That’s why it’s important to have a diverse diet if you’re plant-based, so you can get the nine essential aminos from different sources.)

“You can have, for example, leucine to stimulate the process,” says Luc van Loon, PhD, professor of physiology of exercise and nutrition at Maastricht University Medical Centre. “But you also need the bricks to build the house. You can have all the construction workers present, but if they don’t have the bricks, the house is not going to go up.” By the way, these muscle-building and muscle-repairing properties of amino acids make it critical to keep protein levels up even if you’re injured or not able to exercise, which is, of course, the other way (besides eating) that your body assembles muscle.

45 percent The number of consumers who said they knew how much protein they’d had in the past 24 hours. What about you?
Source: FMCG. Gurus survey.

And although carbs give you fire for a workout, it’s protein that has the staying power. Exercise makes your body more sensitive to those muscle-growing properties of amino acids, meaning it will use more of the protein for synthesis. (This effect lasts for 48 hours after a workout.) “You are what you eat, or what you just ate, but if you’re physically active, you’re actually more of what you just ate,” Van Loon says.

Plus, protein slows down carb absorption, preventing blood sugar spikes and crashes, and it’s used to repair tissue, which is how your muscle recovers, allowing you to crush your sweat sessions week after week. “Without protein, you’re doing your body a disservice,” says Dr. Lyon. “You’re fighting against yourself.”

How does your body process protein?

The next hurdle when it comes to protein equality is that the body doesn’t treat all proteins the same, which means the number of grams you see on a label or nutrition chart is not the whole story. To paint the picture, around 85 percent of the protein in egg whites, whole eggs, and chicken is absorbed, compared with about 63, 72, and 75 percent respectively of the protein in mung beans, yellow peas, and chickpeas, according to American Journal of Clinical Nutrition studies.

The lower bioavailability of plant protein may be due to the presence of fiber (fuel for the gut, affecting everything from mood to metabolism) or tannins, which are antioxidants that—in the unintentionally comic world of science definitions—are called “anti-nutritional.”

The Whey Forward: Why does it seem like whey is in every protein powder and energy bar? Because when it’s isolated—it makes up 20 percent of cow’s milk protein—whey wins the Most Likely to Stimulate Muscle Protein Synthesis award. (Because it’s rapidly digested and absorbed, plus it has a relatively high amount of leucine.) Do you need it? No. “The difference we see with consuming protein via whey or via milk is minimal,” says Van Loon. If you’re an elite athlete who needs every edge, adding whey may matter. For most of us, not so much. But, it’s great to know that whey does a body good.

So, while you can mix your plant proteins to make sure you’re getting all nine aminos with a varied diet, the volume of food you’ll need to eat can be…a lot. “For example, four ounces of skinless chicken breast provides about 31 grams protein and 155 calories,” says Gropper. “To get the same amount of protein, one would need to consume 1.5 cups legumes, 1.5 cups rice, and 1 cup veggies, and the calorie count is closer to 700.”

You’ll get other nutrients and fiber with the larger offering, for sure, but we’re mainly talking protein and overall volume here, for comparison’s sake.

But plant protein is hands-down better for a longer life span, right? Well, not so fast.

That thinking is shifting. Take the case of cholesterol—once the reason we were told to limit eggs and shellfish. Guidelines that suggested Americans limit dietary cholesterol were nixed in 2015 because experts concluded that these foods, turns out, did not increase risk for heart disease. Quite a shift from the egg-fearing decades! (Also, if you need another reason to embrace eggs: They are considered the gold standard of protein quality and digestibility because they contain all nine essential amino acids and almost every vitamin and mineral our bodies require.)

Saturated fat has also been somewhat rehabilitated—at least, the sat fat found in whole foods, like lean beef or full-fat Greek yogurt. The recommendation to limit it to no more than 10 percent of total calories “is not supported by rigorous scientific studies,” concluded a study in Nutrients. Other research suggests it’s more important to consider the overall nutritional profile of a food than any individual macro (or micro) nutrient.

When it comes to cancer, while there’s currently no data showing that strict veganism, i.e., no animal protein whatsoever, is better for outcomes, there is a strong association between whole-food, plant-based diets and lower incidence of several cancers such as breast, ovarian, and colon cancer, says Neil Iyengar, MD, a medical oncologist specializing in breast cancer at Memorial Sloan Kettering.

Iyengar, who studies the effect of diets on cancer, recommends shooting for 20 to 30 grams of fiber per day, plus a diet in which fat is less than 35 percent of total caloric consumption. (If you are vegan for ethical reasons, all of this may be completely moot.)

Is it possible to get enough protein on a plant-based diet?

To be clear, hitting protein needs with a whole-foods plant-based diet can be done, but you’ll have to really plan if you don’t want “an astronomical amount more carbohydrates,” says Dr. Lyon. “Most people are not training hard enough nor can their physiology handle a high-carb diet in order to get the protein.”

While that is one expert’s take, it’s beneficial to know that processed soy products like burgers and sausages, along with high-quality vegan protein sources like mycoprotein (such as Quorn) and seitan, can also be high in salt and fat. One solution might be plant protein isolates and concentrates, where the fiber is removed, so you better absorb them.

But if you’re vegan for sustainability reasons, it’s worth considering that processed plant foods cost energy and produce carbon dioxide. What’s more, we don’t know exactly what is in some of them nor their long-term implications.

The bottom line on protein

What we do know is that we’ve been eating animal proteins (and whole plants) for 300,000 years, and studying the effects for decades, even if protein is only just now getting its time in the limelight. Protein is essential for optimizing the quality of somebody’s life—and to prolonging it, says Dr. Lyon. “The more muscle mass you have, the better your survivability.”

For Forrest, the return to meat, in limited amounts, was a reset. “I feel like this is how our bodies are meant to eat,” she says, noting that it’s much easier to balance her meals and her blood sugar. It’s also a reminder of her power and her ability to decide what’s right for her. “It felt rebellious,” she says. “But also: This is my health, and I had to make a change.”

She’s not the only one. Experts, too, are shaking things up to take full advantage of protein. Johnston, who’s been studying nutrition for more than 40 years, recently changed her diet. “Even though I’m a nutritionist, I didn’t eat much breakfast, but now I make a point of getting the protein in the early morning,” she says. (Her top picks are cheese and eggs—she’s a lacto-ovo vegetarian—and she recommends yogurt to people with limited time or ability to face breakfast.)

“Of course you want to be strong,” she says. “But there are so many proteins that your body makes [via the essential amino acids coming in from food], so having the ability to create them all day is critical.” Time to pump up that protein.

This article originally appeared in the December 2022 print issue of Women's Health.

You Might Also Like

• Jennifer Garner Swears By This Retinol Eye Cream

• These New Kicks Will Help You Smash Your Cross-Training Goals