Registered Dietitian
Registered Dietitian
Jillian Kubala, MS, RD is a Registered Dietitian based in Westhampton, NY. She holds a master’s degree in nutrition from Stony Brook University School of Medicine as well as an undergraduate degree in nutrition science.
Image by Ina Peters / Stocksy
September 03, 2024
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.
Here’s what you need to know about the high-protein, low-carb diet, including health benefits, potential side effects, and how to follow this eating plan in a healthy, sustainable way.
What is the high-protein, low-carb diet?
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.
In order to be considered a “low-carb” diet, a diet must contain less than 130 grams of carbs1 or less than 26% of total calories from carbs per day. To put this into perspective, 130 grams equates to a little more than 8.5 slices of bread.
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.
However, the high-protein, low-carb eating pattern is flexible, meaning some people may eat more carbs and less protein, while others eat fewer carbs and more protein.
Summary
High-protein, low-carb diets are eating patterns that provide less than 130 grams of carbs and significantly more protein than the current RDA.
The importance of protein
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.
“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.
Limiting or at least cutting back on carb intake allows more room for protein-rich foods and usually leads to a reduced intake of ultra-processed foods rich in refined carbs like snack foods and desserts.
Summary
The RDA for protein is the minimum you need to avoid nitrogen imbalance and other health issues. Most people—even those who aren’t following the HPLC diet—will want to consume more than that; at least 100 grams per day.
Benefits of eating high-protein, low-carb
Here are the top evidence-backed benefits of high-protein, low-carb diets:
1.
It may support weight loss.
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.
2.
It’s helpful for blood sugar levels.
Diets low in carbs and higher in protein have been shown to reduce both short- and long-term markers of blood sugar control in people with11 and without12 Type 2 diabetes.
3.
It could help reduce visceral fat.
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.
A 2021 study14 published in Nutrients found that adults who were overweight or had obesity and who followed a low-carb, higher-protein diet for 15 weeks lost 6.4% more visceral fat than those assigned to a low-fat, high-carb diet.
4.
It’s effective for lowering triglyceride levels.
Reducing overall carb consumption and increasing protein consumption could help reduce triglyceride levels16, as long as you’re consuming an appropriate amount of calories.
5.
It can help you maintain muscle mass.
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.
How it compares to other diets
Because there’s no set definition of a high-protein, low-carb diet, it’s flexible and can fit into a variety of eating styles. But here’s a bit more on how high-protein, low-carb diets compare to other popular eating patterns:
- Intermittent fasting: Intermittent fasting (IF), or time-restricted feeding, can be used with any diet, including high-protein, low-carb diets. For example, some people combine a low-carb way of eating with IF methods like 16:8, which entails eating within an eight-hour window and then completely fasting for 16 hours.
- Keto: The ketogenic diet has a very specific macronutrient ratio in order to reach and maintain a metabolic state called ketosis, where the body burns fat for fuel. Eating too much h protein or carbs could interfere with this process. For this reason, carb intake is kept very low and protein intake is kept to a moderate level.
- Atkins: The Atkins diet is a type of low-carb diet. Although it provides more protein than the RDA, it’s not considered a high-protein diet. In order to follow the Atkins diet, you must stick to specific macronutrient ranges, which change as the diet progresses.
- Mediterranean diet: The Mediterranean diet is not a low-carb or high-protein diet. It’s rich in whole, nutrient-dense foods like beans, vegetables, and nuts, many of which are high in carbs. This way of eating is high in fiber, healthy fats, and an array of beneficial plant compounds, which is why it’s been linked to a number of health benefits, like a reduced risk of heart disease20.
Summary
A high-protein, low-carb diet is flexible, so it differs from diets with set macronutrient ratios like the keto diet and the Atkins diet. It’s also lower in carbs than the Mediterranean diet. Intermittent fasting is a method that can be used with almost any eating pattern, including a high-protein, low-carb diet.
Foods to eat
Even though high-protein, low-carb diets can include a variety of foods—depending on the strictness of the diet and the macro ratio you choose to follow—most people following this way of eating prioritize the following protein-rich and low-carb meals and snacks such as the following:
- Eggs
- Poultry like chicken and turkey
- Fish and shellfish
- High-protein dairy products like Greek yogurt and cheese
- Red meat like beef and bison
- Tofu
- Plant-based or animal-based protein powders
- Low-carb vegetables like greens, broccoli, asparagus, and cauliflower
- Nuts, seeds, and nut butters
Foods to avoid or eat in moderation
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.
Here’s a list of carb-rich foods that should be limited when following a high-protein, low-carb diet:
- Breads and baked goods
- Sugar and sweeteners like maple syrup
- Grains and pasta
- Fruits and fruit juice
- Beans and lentils
- Starchy vegetables like corn and peas
- High-carb snack foods like chips and crackers
Your carb restriction will depend on your chosen macronutrient range. You can enjoy carb-rich foods like starchy vegetables, fruits, and beans in moderation as long as you’re not exceeding your carb limit for the day.
A 3-day HPLC meal plan
If you’re interested in trying out some high-protein, low-carb meals or want to get started on a high-protein, low-carb diet, check out this three-day meal plan that’s packed with nutrients like fiber, protein, and healthy fats throughout breakfast, lunch, and dinner.
Day 1
Make it your own: When you’re following a high-protein, low-carb diet, one of the easiest—and most nutritious—ways to start your day is with eggs. “To boost protein content I’ll add a whisked egg into savory soups, or top just about anything with a sunny-side-up egg: salad, grain bowls, avocado toast, even pizza,” Moon says.
Day 2
Make it your own: “According to a meta-analysis21, the healthiest protein foods for heart health are high-quality plant protein foods and seafood,” Moon tells mindbodygreen. To bump up your protein intake, try adding some of Moon’s favorite sources like tofu, arctic char, seabream, and Alaskan cod to dishes like protein bowls.
Day 3
Make it your own: To add another source of plant-based protein to your salad, Moon recommends adding nuts. “I top my salads with nuts instead of croutons to increase the protein content of the meal,” she says. Not only will nuts add a satisfying source of protein, but they’ll also add some crunch.
How to stay healthy on a high-protein, low-carb diet
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.
Here are a few helpful tips for staying healthy on a high-protein, low-carb diet.
- Don’t forget about fiber: Make sure you’re taking in plenty of fiber to support digestive health. Fortunately, many low-carb foods like nonstarchy vegetables, nuts, and seeds are high in fiber.
- Don’t go overboard on protein: As long as you’re incorporating protein-rich foods in all of your meals and snacks, chances are you’ll hit your protein needs. It’s not necessary to guzzle protein shakes multiple times per day. Here’s a primer on how to add protein to your diet without going overboard.
- Pile on the veggies: Nonstarchy veggies like greens, broccoli, asparagus, and cauliflower are excellent sources of fiber and micronutrients like vitamins and minerals. Try to add a variety of nonstarchy veggies to most meals and snacks.
- Low-carb doesn’t mean no-carb: If you’re new to lower-carb diets, consider transitioning to a more moderate low-carb, high-protein diet. Even though very low-carb diets can benefit some people, they’re highly restrictive and are more likely to cause side effects, like headaches and fatigue, compared to more moderate low-carb diets.
- Stay hydrated: Staying hydrated can help you feel your best and promote digestion, which is important when you’re transitioning to a lower-carb diet. Make sure to sip on low-carb beverages like herbal tea, sparkling water, or water flavored with lemon or lime throughout the day.
What about if you don’t eat meat?
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.
Cannon says it’s easier for vegetarians to follow a high-protein, low-carb diet if it includes high-quality dairy, which provides a good amount of protein per serving. Eggs are another high-protein option for people who don’t eat meat.
Side effects and considerations
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.
“It all comes down to how animal-based proteins are raised and prepared. If you’re consuming protein from farms that use regenerative agriculture, those are the protein sources that are most sustainable,” Cannon tells mindbodygreen. Here’s a comprehensive primer on how to eat meat more sustainably.
Summary
Most of the side effects from a HPLC diet occur because of carb restriction. It’s important to pay attention to your body and eat more carbs if you experience symptoms like headaches, fatigue, constipation, and irritability. And when increasing your protein intake, you’ll want to pay attention to how your diet impacts the environment. Choose ethically and sustainably sourced proteins whenever possible.
Frequently Asked Questions
Can I lose weight on a high-protein, low-carb diet?
As long as you’re in a calorie deficit, then yes. While some diets have been shown to be more effective compared to others for promoting fat loss, the most important factor in any weight loss diet is to take in fewer calories than you burn.
What are the side effects of a high-protein, low-carb diet?
If you’re following a more moderate high-protein, low-carb diet, you shouldn’t experience significant side effects. Those who follow a very low-carb diet may experience symptoms like headache, fatigue, and constipation.
Can I do a high-protein, low-carb diet with intermittent fasting?
Yes, IF can be used with any diet you choose to follow. If you’re new to IF, consider starting with a shorter fasting window before moving on to longer fasts to see how your body reacts.
The takeaway
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.
It may be effective for weight loss, blood sugar regulation, and lowering triglycerides. Plus, it could help you maintain muscle mass during weight loss. However, like most diets, it does come with a few downsides, especially if you choose to significantly limit carbs or eat proteins that are taxing on the environment.
