High-Protein, Low-Carb Diet: What It Is + How To Follow It Healthily

The dieting world seems to thrive on extremes. From keto to Atkins, popular diets rarely provide moderate amounts of macros. Take, for example, the high-protein, low-carb diet—a way of eating that restricts carbs while emphasizing protein-rich foods.

Although this eating pattern may provide a few health benefits, more restrictive versions can be hard to follow and may lead to unpleasant side effects. 

A high-protein, low-carb (HPLC) diet is an eating pattern that emphasizes protein and restricts carbs. Unlike other diets, like the ketogenic diet, there's no set definition of a high-protein, low-carb diet, so people following this way of eating may take in different macronutrient ratios.

High-protein diets provide more protein than the Recommended Dietary Allowance (RDA), which currently sits at 0.8 gram of protein2 per kg of body weight or 0.36 gram per pound. This equates to 54 grams of protein per day for a 150-pound person or 10% of total daily calories for a standard 2,000-calorie diet. Most high-protein diets provide between 1.8 and 3 grams3 of protein per kg or 0.8 to 1.36 grams per pound of body weight per day.

Let's translate this to what goes on your plate: A person following a 2,000-calorie high-protein, low-carb diet may take in 40% of their calories from protein, 25% from carbs, and 35% from fats. This would equate to 200 grams of protein and 125 grams of carbs per day and around 1.4 grams of protein per pound for a 150-pound person.

Before we dive into the potential benefits of high-protein, low-carb eating patterns, it's important to note that some experts argue that diets that are considered "high" in protein should actually be considered standard protein diets.

That's because the RDA for protein is the absolute minimum amount of protein that most adults need to meet basic health requirements, like preventing muscle loss and meeting nitrogen needs. 

This means that some diets considered to be "high" in protein may actually be closer to optimal for most people4, especially those with increased protein needs like older adults, physically active people, and pregnant women.

"We find from a metabolic standpoint, working predominantly with women, that if they get below 100 grams per day5, they lose most of the benefits of protein: fatty acid metabolism, insulin sensitivity, weight loss, satiety," Don Layman, Ph.D., a leading protein and amino acid requirements researcher, says on the mindbodygreen podcast.

Studies have linked both high-protein6 and low-carb diets7 to weight loss. Following a low-carb, high-protein diet may support fat loss by decreasing appetite and energy intake.

"Protein has that satiety factor. Research suggests8 higher protein diets increase satiety compared to lower protein diets, which may help you eat fewer calories," dietitian Maggie Moon, M.S., R.D., tells mindbodygreen.

For example, a 2020 study9 published in Nutrients found that people with obesity who followed a low-carb, high-protein diet providing 30% carbohydrate, 30% protein, and 40% fat for four weeks lost 58% more weight than study participants who followed a higher-carb Mediterranean diet that provided 55% carbohydrate, 15% protein, and 30% fat. 

Carbs have a more significant impact on blood sugar10 levels than other macronutrients, so reducing your overall carb intake can be a way to regulate blood sugar. Plus, proteins help slow digestion, which slows the absorption of sugar into your bloodstream.

Visceral fat is a type of deep belly fat that surrounds your internal organs. Having too much visceral fat significantly increases the risk of health conditions13 like Type 2 diabetes.

Studies show that bumping up your protein intake when following a lower-calorie diet for weight loss can help prevent weight-loss-associated muscle loss.

Maintaining muscle mass is important for many reasons, including maintaining a healthy resting metabolic rate (RMR)17 or the number of calories you burn while at rest.   

When you're on a high-protein, low-carb diet, you'll want to reduce your intake of high-carb foods. People following moderate versions of this diet can enjoy carb-rich foods more frequently, while people following stricter versions will want to significantly limit carbs.

If you'd like to transition to a high-protein, low-carb diet, it's important to do it in a healthful way. It's not necessary to severely limit your carb intake or go overboard on protein-rich foods.

High-protein, low-carb diets can be tricky to follow for people on plant-based diets. This is because plant-based proteins, like legumes, usually contain a good amount of carbs.

"It's challenging to meet protein needs on a vegan/vegetarian diet while also restricting carbs," dietitian and sustainability advocate Abby Cannon, J.D., R.D., CDN, tells mindbodygreen. 

"Beans, lentils, peas, and whole grains are high in carbohydrates and typically form a large part of a vegan/vegetarian diet. In order to meet protein needs without them, you have to eat more soy products and nuts and seeds," she says.

High-protein, low-carb diets can cause some side effects. However, these side effects are usually related to more significant carb restriction.

For example, very low-carb diets like the keto diet can lead to symptoms22 like headaches, fatigue, constipation, and irritability. Cutting carbs too severely can also lead to low blood sugar. This is another reason why more moderate low-carb diets are better suited to most people.

In terms of protein, studies show that even extremely high-protein diets are generally safe and not associated with adverse side effects, even when followed for a long time period.

A 2016 study23 published in the Journal of Nutrition and Metabolism found that following a high-protein diet that provided between 2.51 and 3.32 grams per kg or 1.14 and 1.5 grams per pound per day for one year had no harmful effects on any measures of health in athletic men. 

Another important thing to consider is protein sources. Diets high in certain types of animal proteins, like red and processed meats, have been associated with an increased risk24 of certain health conditions, like colon cancer.

Plus, there are environmental concerns25 with eating a diet super high in animal protein.

The high-protein, low-carb diet is a way of eating that emphasizes protein-rich foods and limits carbs. This diet is flexible and can be tailored to your macronutrient preferences.