Nutrition

Protein Per Calorie: The Most Efficient Protein Sources Ranked

Most protein lists rank foods by grams per 100g — but that ignores calories. Here are the best protein sources ranked by how much protein you actually get per calorie.

📅 July 17, 20269 min read

Almost every “high protein foods” list ranks foods by grams of protein per 100g. That sounds sensible — until you realise it completely ignores calories. A food that delivers 25g of protein per 100g but packs 400 calories is very different from one that delivers 22g per 100g at only 120 calories.

If you are tracking macros and trying to hit a protein target within a calorie budget, the metric that actually matters is protein per calorie — how many grams of protein you get for every calorie you consume.

The formula:Protein Efficiency = grams of protein ÷ total calories. Multiply by 100 to express it as “grams of protein per 100 calories.” The higher the number, the more protein you get for your calorie budget.

Why Protein Per Calorie Matters More Than You Think

If you are eating at maintenance or in a caloric deficit — which most people tracking macros are — every calorie counts. Choosing a protein source with a better protein-to-calorie ratio means you can hit your protein target while leaving more room in your budget for carbohydrates, fats, vegetables, and the foods you actually enjoy.

Conversely, when you are bulking and caloric density is less of a concern, you have more flexibility. But even then, knowing the efficiency of your protein sources helps you build meals more deliberately.

The Ranking: Best Protein Sources by Protein Per Calorie

The table below ranks common protein foods by grams of protein per 100 calories. Values are based on cooked weight where applicable (since that is how you actually eat them).

FoodProtein per 100 calApprox. calories per 100gNotes
Egg whites (cooked)~26g~52 kcalHighest efficiency of any whole food
Canned tuna in water~24g~86 kcalOne of the best value proteins
Chicken breast (grilled)~23g~110 kcalThe classic lean protein
Shrimp (cooked)~22g~99 kcalLow fat, very lean
Turkey breast (skinless)~22g~104 kcalUnderrated protein source
Cod / white fish (baked)~21g~105 kcalExtremely lean
Low-fat cottage cheese~14g~72 kcalSlow-digesting casein protein
Greek yogurt (0% fat)~13g~59 kcalGood protein, some carbs
Pork tenderloin (roasted)~18g~143 kcalLeaner than most people think
Lean ground beef 95% (cooked)~15g~152 kcalGreat flavour, good efficiency
Salmon (baked)~12g~206 kcalHigh in omega-3s, less efficient but worth it
Whole eggs (boiled)~8g~155 kcalFat adds calories vs. whites
Tempeh~10g~195 kcalBest plant-based option
Edamame (shelled)~9g~122 kcalHigh fibre, good amino profile
Regular ground beef 80% (cooked)~9g~215 kcalFat significantly drops efficiency
Cheddar cheese~6g~402 kcalVery calorie dense, low efficiency
Peanut butter~4g~588 kcalMostly fat — not a primary protein source

💡 Reading the table

Egg whites at 26g per 100 calories are the most efficient protein in existence. Peanut butter at 4g per 100 calories is not really a protein food — it is a fat food with some protein. Both can have a place in your diet, but knowing the difference stops you from accidentally blowing your calorie budget chasing protein grams.

The Big Surprises in This List

Pork Tenderloin Beats Salmon

Salmon is widely seen as a “healthy protein,” which it is — but its fat content means it delivers less protein per calorie than lean cuts of pork, chicken, or white fish. That does not make salmon worse; omega-3 fatty acids are genuinely valuable. It just means that if pure protein efficiency is your goal, pork tenderloin (which most people dismiss as fatty) actually outperforms it.

Pork tenderloin is one of the leanest cuts of meat available, with a protein-to-calorie ratio similar to chicken breast. See our pork recipes if you want to start using it more.

Ground Beef: Lean vs. Regular

The difference between 95% lean ground beef and 80% lean ground beef in protein efficiency is dramatic. Switching from 80% to 95% lean almost doubles your protein per calorie. If you are eating ground beef several times a week as a protein source, this single swap can make a meaningful difference to your numbers.

Whole Eggs vs. Egg Whites

Whole eggs are nutritionally excellent — they contain vitamins, healthy fats, and choline that egg whites lack. But if you are purely optimising for protein efficiency, egg whites are in a category of their own. A practical middle ground: use 2 whole eggs plus 3–4 egg whites. You get the nutrients from the yolks and the protein efficiency boost from the whites.

How to Use This in Practice

Protein efficiency is a tool, not a religion. Here is how to apply it without overcomplicating your diet:

  • Build your main protein sources around high-efficiency foods (chicken breast, turkey, tuna, shrimp, white fish, egg whites). These do the heavy lifting.
  • Allow moderate-efficiency foods (salmon, whole eggs, lean ground beef, pork) as your main meals — they deliver great nutrition alongside good protein.
  • Treat low-efficiency foods (cheese, peanut butter, nuts) as add-ons for flavour and healthy fats, not primary protein sources.
  • Use Greek yogurt and cottage cheese as convenient high-efficiency protein boosts — great in smoothies, as snacks, or mixed into recipes.
Practical target: If you can keep your average protein efficiency above 15g per 100 calories across your main protein sources, hitting 150–180g of protein on a 2,000–2,200 calorie diet becomes straightforward.

Plant-Based Protein Efficiency

Plant proteins generally score lower on this metric because they tend to come packaged with more carbohydrates and fats. However, a few plant sources are genuinely competitive:

Plant FoodProtein per 100 calNotes
Tempeh~10gBest complete plant protein
Edamame~9gComplete amino acid profile
Tofu (firm)~11gVaries by firmness
Lentils (cooked)~8gHigh fibre, incomplete protein
Black beans (cooked)~6gGreat fibre and iron
Chickpeas (cooked)~5gVersatile but calorie-denser
Seitan~20gExtremely high efficiency — if you tolerate gluten

For vegetarians and vegans, seitan (wheat gluten) is remarkable — it rivals chicken breast in protein efficiency. Tempeh and edamame are the other standouts. Combining plant proteins across a day covers any amino acid gaps without needing to be precise about pairing at every meal.

Building a High-Efficiency Protein Day

Here is an example of what a high-efficiency protein day looks like, targeting 160g of protein at around 2,000 calories:

  • Breakfast: 3 whole eggs + 3 egg whites scrambled with cottage cheese (~40g protein, ~350 kcal)
  • Lunch: 180g grilled chicken breast with roasted vegetables (~44g protein, ~320 kcal)
  • Snack: 200g Greek yogurt (0% fat) with berries (~24g protein, ~180 kcal)
  • Dinner: 200g baked cod with rice and broccoli (~42g protein, ~550 kcal)
  • Post-workout: 200g low-fat cottage cheese (~22g protein, ~160 kcal)

Total: ~172g protein at ~1,560 calories from protein sources alone, leaving ~440 calories for cooking oils, sauces, and extras. This is sustainable, varied, and built entirely around high-efficiency choices.

💡 Quick kitchen tip

Keep canned tuna in water, low-fat cottage cheese, Greek yogurt, and frozen shrimp permanently stocked. These four foods are the fastest route to hitting your protein numbers when you are short on time — all high efficiency, no cooking required for two of them.

The Bottom Line

Grams of protein per 100g is a useful starting point, but protein per calorie is the number that actually matters when you have a calorie target to hit. The practical takeaway is simple: centre your meals around chicken breast, turkey, white fish, tuna, shrimp, and egg whites — then layer in higher-calorie proteins like salmon and whole eggs for nutrition and enjoyment.

If you want recipe ideas built around the most efficient protein sources on this list, browse our chicken, fish, and turkey categories — every recipe shows the exact protein and calorie counts upfront so you can make fast, informed decisions.