Protein is proven to help you shed pounds. That doesn’t mean simply eating more of it and calling it a day.
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When it comes to weight loss, protein isn't exactly the most ground breaking nutrient. Recall, for example, the Atkins diet, the well-known low-carb, high-protein diet on which you could eat bacon and burgers (hold the bun) and still lose weight. And while it was a hot topic as recently as the early 2000s, "the concept actually dates back to the '60s," says Ken Fujioka, M.D., endocrinologist and director of the Nutrition and Metabolic Research Center at the Scripps Clinic in San Diego. "It keeps being recycled because it does work."

Protein's runaway popularity may have started with Atkins, but it certainly didn't end there. It bears a health halo to this day, beloved by dietitians and gym-goers alike for its ability to promote healthy weight loss. But reaping its many benefits is not as simple—or as straightforward—as filling your plate with steak and eggs.

Let's start with a quick refresher in physiology: proteins are incredibly important just to keep the body running. Amino acids, which are the building blocks of proteins, serve as the precursors for hormones. On top of that, "protein is needed to repair the body," says Fujioka. "Liver cells, kidney cells, bones: they're always breaking down and remodeling. If you don't have protein, you can't do that—so protein is a limiting factor." The current recommended daily allowance of protein is 0.8 gram per kilogram of body weight, so consider that your minimum.

Can Protein Help You Lose Weight?

Increasing your protein intake beyond that might be helpful for those looking to shed some pounds as long as it does not mean excess calories. "It can help with weight in that it can balance satiety, or our fullness factor," says Melissa Majumdar, M.S., a registered dietitian at Emory University Hospital and a spokesperson for the Academy of Nutrition and Dietetics. While calorie restriction is typically required for weight loss, loading up on protein-rich foods can help you feel satisfied (and therefore less hungry) even within those caloric constraints.

This relates to hormones, which can trigger the body's cues for both hunger and fullness. "When we eat a meal and it gets into our small intestines, we release hormones to tell us to stop eating—and protein is the best at [making us feel full]," explains Fujioka. To be specific, protein is better as a satiety signal than its fellow macronutrients, fat and carbohydrates.

Moreover, that fullness factor isn't fleeting. "Studies show that it's both with a single meal—so if your meal contained protein, then it would create more fullness—but also a 24-hour period," says Majumdar. "So, over the course of the day, if there was more protein incorporated, that can control hunger better."

Then there's the fact that protein is a key player for creating muscle mass. "Whenever we lose weight, we naturally lose some of our lean muscle mass, and protein can help preserve that," says Majumdar.

Its role in this respect becomes more important with each passing year. "Your body is constantly turning over these tissues," says Kristen M. Beavers, Ph.D., an assistant professor of health and exercise science at Wake Forest University. The rate of turnover fluctuates over your lifetime. Early on, you build more muscle mass than you lose. Once you hit your 30s and 40s, you're breaking even. After that, there's a loss of roughly 1 to 2% a year.

"One of the concerns we have with recommending weight loss for older adults is that when people lose weight, they want to lose fat—but some of what you lose is muscle and bone," says Beavers. That could potentially lead to functional decline, increase the risk of disability and fracture, and promote all-around fragility. The goal, then, is to lose weight without sacrificing muscle and bone health, and a high-protein diet is a simple way to make that happen.

Finally, another reason protein is so helpful is that your body actually burns calories as it breaks down protein in your gastrointestinal tract, via a process called diet-induced thermogenesis. The process of digesting protein gives your metabolism a slight bump, which is why the "meat sweats" can happen in people who consume a ton of protein (namely, athletes). That said, "it's just an incidental benefit," says Fujioka. The little metabolic boost likely isn't enough to offset the calories you're taking in by eating protein—but it's still there.

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Can You Eat Too Much Protein?

A protein-heavy diet comes with certain considerations, however. First, not everyone needs more protein; the standard American diet contains enough as it is, says Majumdar. And it's helpful to check with your doctor or a registered dietitian before drastically increasing your protein intake, since it's not ideal for people with certain medical conditions. "Some individuals should not drive up their protein intake a lot, such as somebody with liver disease or kidney disease, or a fairly advanced type 2 diabetes," says Fujioka. "Those individuals have to be very careful."

Beyond that, one of the biggest (and best known) concerns is that animal sources of protein, such as beef and pork, can come with saturated fat. And a high intake of saturated fat can increase your risk for heart disease, as well as weight gain. "If you see a lot of fat, particularly saturated fats, you can run into problems,"says Fujioka. "Protein, unfortunately, oftentimes comes with a lot of fat, and so patients really do want to pick either better fat sources or leaner forms of protein." He's a fan of chicken and fish, tofu, eggs, and rice and beans—a pairing, he says, that will "get you all of the essential amino acids."

Beans, seeds, nuts and soy are also all good sources of protein. Unlike most other plant-based proteins, soy contains high amounts of the essential amino acids. Soy-based foods are also highly praised by our experts. "There area lot of people who are down on [soy] because they're worried about the phytoestrogens [being linked to certain cancers], but the data for that is extremely weak," says Fujioka. "When you look at countries that have high soybean diets, they actually do well and actually have lower rates of breast cancer."

Tips to Help You Lose Weight

Eating more protein for the purpose of weight loss works best under certain conditions. A 2020 study published in Advances in Nutrition found that people primarily benefit from a higher protein intake when they're also cutting calories and exercising. Simply adding more protein to your diet and calling it a day won't deliver the weight loss you're looking for. With that in mind, here's how to do it right.

Get Lifting

Weight training is an easy way to retain muscle mass as you're losing weight. A study in Nutrition Journal found that combining resistance training and a high-protein diet led to weight loss as well as to an increase in fat-free mass, or musculoskeletal mass. Not only does this combination help reduce body fat, but it simultaneously replaces that fat with healthy muscle.

Keep It in Balance

"We're not eating just protein,"says Majumdar. "So is it the protein that made you full, or is it that you had a balance of whole grains, protein, fruits and vegetables?" Other nutrients on your plate offer their own benefits for weight loss, partly by impacting your fullness factor. "We know that fat empties slowly and that fiber does also,"she says. For this reason, it's a good idea to balance protein with other nutrients.

Stick with It

Eating seven hard-boiled eggs a day probably won't bring you much joy—or long-term success, says Majumdar. Any successful diet is one that you can stick to on a long-term basis. And it doesn't have to be a calorie-restricted, high-protein diet. To lose weight, says Majumdar, "there's also good evidence to support the DASH diet with calorie restriction, which is one that's used for hypertension. There's evidence to support a Mediterranean diet, which is high in your healthy fats, like olive oil." Although both of these diets highlight fresh fruits and vegetables, these eating plans also contain plenty of protein from sources such as beans, lentils, seafood and lean meats such as chicken. You'll have no problem hitting a standard protein goal, but these diets offer a little more flexibility.

This article first appeared in EatingWell, Protein.