High-protein diet: What is the right amount for gaining muscle mass?

What is a high-protein diet, and who is it for?

A high-protein diet is a dietary plan in which protein accounts for 25 to 40 percent of total calorie intake, compared to 10 to 15 percent in a standard diet. It aims to promote muscle gain, support weight loss while preserving lean body mass, or accelerate recovery after exercise. It is primarily intended for athletes seeking to build muscle mass, people in a caloric deficit who wish to maintain their muscle mass, and patients undergoing nutritional rehabilitation. The thermic effect of protein (20–30% of calories consumed are expended to metabolize it) also contributes to total energy expenditure.

Which protein sources should be prioritized in this diet?

The quality of protein matters just as much as the quantity. The best sources, which provide all the essential amino acids, include:

• Lean meats (chicken, turkey, lean beef) and fatty or white fish.
• Whole eggs and egg whites.
• Fermented dairy products: cottage cheese, skyr, Greek yogurt, and quark.
• Whey and casein: supplements derived from whey; whey is absorbed quickly, while casein is absorbed gradually.
• For vegetarians and vegans: legumes, tofu, tempeh, and quinoa, combined to cover the full amino acid profile.

Plant-based protein powders (pea, rice, hemp) offer a complete alternative for those who avoid dairy products.

How much protein should you consume each day?

Recommendations vary depending on your profile:

• Sedentary individuals trying to lose weight: 1.2 to 1.6 g/kg/day to preserve lean body mass.
• Recreational athlete: 1.6 to 1.8 g/kg/day.
• Athletes or strength trainers: 1.8 to 2.2 g/kg/day.
• Above 2.5 g/kg/day, additional benefits have not been demonstrated, and the risk of kidney problems increases.

Spreading intake over 4 to 5 meals per day (20 to 40 g per meal) maximizes muscle protein synthesis, as muscle cannot store unlimited amounts of protein per meal. The post-workout anabolic window (0 to 2 hours after training) is particularly favorable for protein intake combined with fast-acting carbohydrates, which stimulate insulin release and promote the transport of amino acids to the muscles.

Which protein supplements can be used with this diet?

Several supplements have documented benefits:

• Whey protein: rapid absorption, ideal for post-workout use.
• BCAAs (leucine, isoleucine, valine): limit muscle breakdown during prolonged exercise or when in a calorie deficit.
• Creatine: improves performance during explosive efforts and accelerates athletic recovery.

These supplements are not a substitute for a balanced, nutritious diet and should be chosen based on your fitness level and goals.

How should you plan your meals on a high-protein diet?

A typical meal plan includes protein at every meal, combined with vegetables, complex carbohydrates, and healthy fats:

• Breakfast: vegetable omelet, skyr or cottage cheese, with rolled oats.
• Lunch: grilled chicken or fish, legumes, green salad, and olive oil.
• Snack: Greek yogurt, almonds, or a post-workout serving of whey.
• Dinner: salmon, quinoa, and steamed vegetables.

Hydration is a key factor that’s often overlooked: protein produces nitrogenous waste (urea) that the kidneys must eliminate. Aim for 35 to 40 mL of water per kilogram of body weight per day during periods of intense training.

What risks should you be aware of before following this diet?

Very high protein intake over the long term can put a strain on the kidneys, particularly in people with pre-existing kidney disease. It can also reduce intake of fiber, vitamins, and minerals if the diet is not balanced. Research also suggests a link between excessive consumption of animal protein and an increased risk of cardiovascular disease, due to the saturated fats that often accompany it. To minimize these risks:

• Maintain adequate fluid intake (at least 1.5 to 2 L of water per day).
• Maintain a high intake of fiber, vegetables, and whole grains.
• Include omega-3s to counteract inflammation caused by intense exercise.
• Diversify protein sources by incorporating plant-based options.
• Get an annual kidney function test if your diet remains at high levels over the long term.

Consulting a dietitian or sports medicine physician remains the best way to ensure a personalized and safe plan.