High protein, low carb diets have become increasingly popular as a means of encouraging weight loss while maintaining or increasing muscle mass ( 1 ).
They may have other benefits as well.
Yet, multiple varieties of this eating pattern exist, and many people wonder whether it’s right for their lifestyle.
This comprehensive guide to the high protein, low carb diet describes how it works and details its health benefits, as well as any potential drawbacks.
The high protein, low carb diet swaps much of your daily carb intake for protein.
Although there’s no set macronutrient ratio, this eating pattern is based largely on the allotments of the two diets that inspired it.
For example, low carb diets typically restrict carb intake to under 26% of total daily calories, or fewer than 130 grams of carbs for someone following a 2,000-calorie diet — while very low carb diets slash that number to under 10% ( 2 ).
On the other hand, high protein diets often pack significantly more than the Recommended Daily Allowance (RDA) for protein, providing at least 0.6 grams of protein per pound (1.3 grams per kg) of body weight ( 3 , 4 ).
Some boast over 1.4 grams of protein per pound (3 grams per kg) of body weight — the equivalent of 204 grams of protein daily for a 150-pound (68-kg) person ( 5 ).
High protein, low carb diets may be higher in fat to compensate for the carb deficit.
For instance, a 2,000-calorie version may contain 26% carbs, 40% fat, and 34% protein — equating to a daily protein intake of 170 grams for a 150-pound (68-kg) person.
However, while some people, such as bodybuilders and athletes, pay close attention to macronutrient ranges when following this diet, many individuals simply cut carbs and replace them with high protein foods.
What’s more, some people follow less strict versions that contain 30–35% carbs — although these are technically considered moderate in carbs ( 2 ).
Some of the most popular commercial diets commonly considered high in protein and low in carbs don’t truly fit into both categories.
Notably, many people regard the Zone Diet and Sugar Busters Diet as high protein, low carb. However, these diets are moderate in carbs, as they typically provide about 40% of calories from carbs.
Additionally, many popular low carb diets, such as Atkins and ketogenic diets, are not considered high protein, low carb. Instead, they’re high fat, low carb or high fat, very low carb, and they only contain moderate amounts of protein.
In fact, no branded diets are known to conform to this pattern.
If you’re interested in a strict high protein, low carb diet, you may need to count calories, protein, carbs, and fat to stay within your macronutrient ranges.
This can be difficult, so most people prefer to loosely follow a high protein, low carb diet by replacing high carb foods with protein sources.
SummaryThere’s no set macronutrient range for a high protein, low carb diet, so most people tend to swap much of their typical carb-heavy foods with protein sources.
Although people who lead sedentary lifestyles require less protein, physically active individuals, athletes, and pregnant women need significantly more than the current RDA of 0.36 grams per pound (0.8 grams per kg) of body weight ( 3 ).
As such, high protein diets may provide numerous benefits — as may low carb eating patterns, which are often associated with weight loss.
Thus, combining the two diets may give numerous advantages.
Protein is the most filling macronutrient and helps decrease hunger and food intake, two effects that promote weight loss.
In particular, foods high in protein boost levels of fullness hormones while lowering levels of hunger hormones like ghrelin ( 6 ).
Research has shown that meals comprising 25–81% of calories from protein increase feelings of fullness, meaning that even moderate protein diets may reduce hunger levels ( 6 ).
High protein diets also help enhance the thermic effect of food, or the calories burned during digestion. This may be due to the greater oxygen demand required to break down protein-rich foods ( 6 ).
Additionally, high protein, very low carb eating patterns have been shown to enhance the secretion of glucagon, a hormone produced by the pancreas that’s known to enhance fullness ( 7 ).
These diets also lead to higher ketone body production, particularly of beta hydroxybutyrate (BHB). Your liver produces ketone bodies when glucose availability is reduced. Studies show that increased BHB levels help suppress appetite ( 8 ).
Interestingly, a small 4-week study in men with obesity demonstrated that a reduced calorie, high protein, very low carb diet providing 30% protein and 4% carbs led to more weight loss than a high protein, moderate carb diet providing 30% protein and 35% carbs.
On average, the men in the high protein, low carb group lost 15 pounds (6.75 kg) while those in the moderate carb group lost 10 pounds (4.32 kg) ( 9 ).
Many other studies reveal that high protein, low carb diets are more effective for weight loss than those higher in carbs and protein ( 9 , 10 , 11 , 12 ).
Still, total calorie intake and calorie burning are the most important factors for weight loss.
When you lose weight, it’s normal to experience significant decreases in muscle mass. Yet, this loss can gradually lower your metabolism, as greater muscle mass increases the number of calories you burn while at rest ( 13 ).
High protein diets can help preserve muscle mass during weight loss and may even increase muscle mass.
Increasing protein intake while cutting 500–750 calories per day has been shown to maintain muscle mass while promoting fat loss. However, this effect is lost during more severe calorie restriction, such as during poorly planned, very low calorie diets ( 14 , 15 ).
Additionally, studies show that combining a high protein diet with exercise can boost fat loss while building lean body mass.
In a 4-week study, 20 men who exercised intensely 6 days per week ate either a high protein diet of 1.1 grams per pound (2.4 grams per kg) of body weight or a control diet. Both diets provided 40% fewer calories than their energy needs and around 50% of calories from carbs.
Those following the high protein diet lost more body fat and gained about 3 pounds (1.2 kg) of muscle mass, while the control group’s muscle mass stayed the same ( 16 ).
Other studies note that high protein diets promote increased or stable muscle mass during weight loss for both men and women, compared with lower protein diets ( 10 , 17 ).
Plus, eating a low calorie, high protein diet has been shown to help athletes gain muscle mass during training.
A study in 48 athletes found that those who ate a minimum of 1.4 grams per pound (3 grams per kg) of body weight combined with heavy resistance training gained significantly more muscle mass and less body fat than those who followed their normal diets ( 18 , 19 ).
These results occurred despite the high protein group consuming 490 more calories per day than the control group.
Low carb diets have likewise been shown to help reduce fat mass while maintaining muscle mass ( 20 , 21 ).
High protein, low carb diets may also aid the following:
SummaryHigh protein, low carb diets may promote weight loss, preserve muscle mass, improve blood sugar control, lower your risk of heart disease, and enhance bone health.
High protein, low carb diets may have several drawbacks.
Some studies associate high protein diets with an increased risk of heart disease and heart failure.
In a study in 2,441 men aged 42 to 60, those with the highest total protein intake had a borderline significant 33% greater risk of heart failure than those with the lowest intake ( 28 ).
However, the men with the highest protein intake were also more likely to be overweight and have diabetes, both of which are risk factors for heart failure ( 30 ).
Research has also linked high protein diets — primarily those with lots of animal protein — to an increased risk of certain cancers, including colorectal cancer, as well as negative effects on bone, liver, and kidney health ( 31 , 32 ).
It should be noted that high protein diets are widely considered safe for those with normal kidney function, though those with kidney disease should avoid this eating pattern ( 2 ).
Very low carb diets are also tied to negative effects, including a potentially increased risk of death from all causes. Nonetheless, more high quality, long-term research on the downsides of both low carb and high protein diets is needed ( 2 ).
Many people with moderately active lifestyles simply don’t need all the protein in very high protein, low carb diets, such as those that recommend above 0.9 grams per pound (2 grams per kg) of body weight per day.
For most physically active people, a daily protein intake of 0.54–0.9 grams per pound (1.2–2 grams per kg) of body weight is likely optimal ( 33 ).
Protein needs depend on your sex, body weight, age, health, activity levels, and body composition goals, so you should consult your healthcare provider if you’re unsure how much you should eat.
Moreover, high protein, low carb diets aren’t necessary to promote overall health.
Eating a balanced, nutrient-rich diet, staying within your calorie needs, exercising, and reducing your intake of processed foods and added sugar are much more important to your well-being than your macronutrient ratios.
SummaryHigh protein, low carb diets are linked to a few downsides, including an increased risk of some cancers. Plus, most people have no need for all the protein that this eating pattern encourages.
When following a high protein, low carb diet, it’s important to reduce your intake of carb-rich foods. You should limit the following:
You can include healthy, high carb foods like starchy vegetables and fruits in moderation. Remember that your total carb intake depends on your desired macronutrient ranges.
Depending on your macronutrient goals, you may also need to reduce your intake of high fat foods like fatty meats and oils.
SummaryHighly refined carb foods like pasta, bread, sugar, and sweetened beverages should be restricted during a high protein, low carb diet.
Eating mostly whole, nutrient-rich foods is best on a high protein, low carb diet — as with any healthy diet. You’ll generally want to up your intake of protein.
Foods to eat on this diet include:
Fruits, starchy vegetables, and high protein grains like quinoa can be enjoyed in moderation depending on your level of carb restriction.
Fat intake also depends on your individual dietary regimen. Egg yolks, avocado, nut butters, fatty fish, and olive oil are good choices for healthy fat sources.
SummaryHigh protein, low carb diets emphasize high protein foods like eggs, fish, tofu, and chicken, as well as low carb foods like non-starchy vegetables.
