The Best Protein Sources for Muscle Growth, Ranked
The Best Protein Sources for Muscle Growth, Ranked
If you’re between 20 and 40 and training consistently, you already know that protein is the foundation of muscle protein synthesis. But here’s what matters more than just “eating protein”: not all protein sources are created equal.
In this analysis inspired by Dr. Mike Israetel of Renaissance Periodization, we break down the best (and worst) protein sources for lifters who want to build muscle efficiently without wasting time on low-quality options. From dairy’s dominance to the “peanut butter trap,” here is how you should be fueling your body.
1. The Gold Standard: Dairy (Whey, Casein, & Greek Yogurt)
Dairy isn’t just for kids—it’s biologically designed for growth. Evolutionarily, milk exists to turn a small calf into a massive cow, and that growth potential works for you too.
Top Picks:
- Whey isolate for post-workout (fast-digesting, high leucine content)
- Casein for slow-digesting overnight fuel
- Non-fat Greek Yogurt (or Icelandic Skyr) for a massive protein-to-calorie ratio
Pro Tip: Try “filtered milks” like Fairlife. They filter out the sugars and fats, leaving you with a high-protein drink that fits perfectly into a lean bulk. If you’re following a natural bulking guide, these filtered options make hitting your protein targets much easier without excess calories.
2. The Lean Machine: Egg Whites
Eggs contain nearly the highest quality protein ever studied. While whole eggs are excellent, the calories from the fat in the yolks can add up quickly if you’re eating 6-8 at a time.
Strategy: Use a mix. Start with 1-2 whole eggs for the vitamins and minerals in the yolk, then bulk up the volume with liquid egg whites to hit your 40-50g protein target without the calorie surplus.
3. The Staples: Lean Meats & Seafood
Chicken breast is the classic for a reason, but variety keeps you from quitting your diet.
The Heavy Hitters:
- Chicken/Turkey breast
- 93-96% lean ground beef
- White fish (shrimp, tilapia, cod)
The Warning: Be careful with high-mercury fish like Albacore tuna if you’re eating it multiple times a day. Also, “processed” meats like sausages are often more fat and sodium than actual muscle-building fuel.
4. High-Quality Vegan: TVP & Soy Isolate
Think vegan protein is just salad? Textured Vegetable Protein (TVP) is an excellent source for muscle growth because it’s a complete protein that mimics the texture of ground meat.
The Strategy: Look for pea and rice blends. Neither is perfect alone, but together they create a complete amino acid profile similar to whey. Soy isolate also provides all essential amino acids and has been shown in research to support muscle protein synthesis at rates comparable to animal proteins.
5. The “Peanut Butter Trap”: Low-Quality Sources
This is where most lifters fail. They see “8g of protein” on a jar of peanut butter and think they’re winning.
The Reality Check: Peanut butter is a fat source, not a protein source. To get 30g of protein from peanut butter, you’d have to eat over 1,000 calories of fat.
Collagen & Bone Broth: These are great for your skin and joints, but they are incomplete proteins. They do almost nothing for actual muscle protein synthesis because they lack the essential amino acids (particularly leucine) that trigger muscle growth. Don’t count them toward your daily protein goal.
How to Structure Your Day
For maximum hypertrophy, research supports aiming for approximately 1 gram of protein per pound of body weight (or 2.2g per kg). For details on exactly how much protein you need based on whether you’re bulking, cutting, or maintaining, check out our detailed guide.
Split this into 4-5 evenly spaced meals to keep your body in a positive protein balance throughout the day. This isn’t about a mythical “anabolic window”—it’s about consistent availability of amino acids for repair and growth.
Track Your Progress
Knowing what to eat is only half the battle—tracking whether you’re actually consuming enough quality protein and pairing it with effective training is what separates those who make progress from those who spin their wheels.
With SetsApart, you can track your hard sets per muscle group and see if your training volume matches your nutrition efforts. If you’re eating right but not progressing, the data will tell you whether you need to adjust your training stimulus.
The Bottom Line: If you want to build muscle like you mean it, eat like it. Prioritize Tier 1 sources (Dairy, Eggs, Lean Meat) and stop counting the “trace proteins” in your bread and nut butters as your main muscle-building blocks.
Source
This article was inspired by and summarizes key insights from the following video. Check out the video for more detail and subscribe to the channel—it’s a great resource for evidence-based training.
Watch the full video: The Best Protein Sources Tier List - Dr. Mike Israetel
