Egg whites top the list. A single egg white delivers 3.6 grams of protein for just 17 calories, which works out to about 4.7 calories per gram of protein. That ratio is nearly impossible to beat with whole food. But egg whites aren’t the only standout, and the best choice for you depends on whether you eat animal products, how you cook, and what you actually enjoy eating.
How to Compare Protein Density
The simplest way to rank foods by protein efficiency is to divide calories by grams of protein. The lower that number, the more protein you’re getting per calorie. Bariatric nutritionists use a quick version of this called the 10:1 rule: multiply the grams of protein by 10, and if the calorie count is higher than that number, the food is relatively inefficient. A food with 20 grams of protein should have no more than 200 calories to pass the test.
By that standard, egg whites score around 4.7:1, boneless skinless chicken breast lands near 5.3:1, and most fish fillets fall somewhere in between. Anything under 10:1 qualifies as a strong protein source. Anything under 6:1 is exceptional.
The Top Animal-Based Options
Egg whites are the clear winner on pure numbers. Because the yolk contains nearly all of the fat and most of the calories in an egg, removing it leaves you with an almost pure protein source. A whole egg has 71 calories and 6.3 grams of protein, giving it a ratio of about 11.3:1. Separating out the white cuts that ratio by more than half. Liquid egg whites sold in cartons make this easy since there’s no cracking or separating involved.
Boneless, skinless chicken breast comes in second among whole foods, with 112 calories and roughly 21 grams of protein per 100 grams raw. That’s a ratio of about 5.3:1. Cooking method matters here. Grilling or baking keeps the calorie count stable, while breading and frying can double or triple the calories without adding meaningful protein. Turkey breast performs almost identically.
White fish like cod, tilapia, and pollock rival chicken breast. A 100-gram serving of cod typically provides around 80 to 90 calories and 17 to 20 grams of protein. Shrimp is another strong performer, landing in a similar range. Canned tuna packed in water is one of the most convenient options, delivering comparable numbers with no cooking required.
Nonfat Greek yogurt deserves a mention too. A typical serving has around 100 calories and 17 grams of protein, putting it right at the edge of the 6:1 range. It also scores extremely well on protein quality. Dairy proteins rank among the highest on the DIAAS scale, a measure of how completely your body can absorb and use the amino acids in a food. Whey and milk proteins consistently score above 100 on that scale for adults, meaning your body uses virtually all of the protein they contain.
The Top Plant-Based Options
Seitan is the plant-based protein champion by a wide margin. Made from vital wheat gluten, it packs about 21 grams of protein into just 104 calories per 28-gram serving. That puts it in the same territory as chicken breast. A 100-gram serving of prepared seitan typically delivers 25 grams of protein. The catch: seitan is pure wheat gluten, so it’s off the table if you have celiac disease or a gluten sensitivity. It’s also lower in the amino acid lysine, so pairing it with beans or lentils over the course of the day rounds out the profile.
Lupini beans are a lesser-known option worth knowing about. Protein makes up as much as 40% of their dry weight, which is significantly higher than most other legumes. They’re also unusually high in fiber and low in digestible carbohydrates, with less than 10% carbohydrate content. You can find them jarred in brine at many grocery stores, ready to eat as a snack.
Tempeh offers about 20 grams of protein per 100-gram serving but carries more fat and calories than seitan. Tofu, particularly the extra-firm variety, is lighter on protein but still passes the 10:1 test when you choose the right brand. Edamame is another solid pick, with roughly 11 grams of protein and 120 calories per cup.
Why Protein Quality Matters Too
Not all protein grams are created equal. Your body needs a specific set of amino acids to build and repair tissue, and different foods supply those amino acids in different proportions. Animal proteins, dairy, and eggs deliver a complete set in ratios your body uses efficiently. Most plant proteins are lower in one or two key amino acids, which means your body can’t use 100% of what you eat for muscle-building purposes.
This doesn’t mean plant proteins are bad. It means that if you’re relying entirely on plants, variety matters. Combining grains with legumes, or eating seitan alongside beans at some point during the day, fills in the gaps. If you eat any animal protein at all, your amino acid needs are almost certainly covered without thinking about it.
Protein Burns More Calories During Digestion
There’s a bonus built into high-protein foods that doesn’t show up on the nutrition label. Your body spends energy digesting food, a process called diet-induced thermogenesis. Protein costs significantly more energy to digest than fat or carbohydrates. Digesting fat burns 0 to 3% of the calories consumed. Carbohydrates burn 5 to 10%. Protein burns 20 to 30%.
In practical terms, if you eat 200 calories of chicken breast, your body uses 40 to 60 of those calories just processing it. That same 200 calories from oil would cost your body almost nothing to digest. This means the “net” calorie impact of high-protein foods is even lower than the label suggests, which is one reason high-protein diets consistently outperform other approaches for fat loss in research studies.
Quick Reference: Calories Per Gram of Protein
- Egg whites: ~4.7 calories per gram of protein
- Cod/white fish: ~4.5 to 5.0 calories per gram of protein
- Boneless skinless chicken breast: ~5.3 calories per gram of protein
- Shrimp: ~5.5 calories per gram of protein
- Seitan: ~5.0 calories per gram of protein
- Nonfat Greek yogurt: ~5.9 calories per gram of protein
- Canned tuna in water: ~5.0 calories per gram of protein
- Tempeh: ~9.5 calories per gram of protein
The foods at the top of this list aren’t necessarily the ones you should eat exclusively. The best high-protein, low-calorie food is the one you’ll actually prepare and enjoy eating consistently. Chicken breast is less efficient than egg whites on paper, but it’s far more versatile as the center of a meal. Seitan is remarkable for a plant food, but it won’t help you if you never cook with it. Pick two or three options from this list that fit your preferences and rotation, and you’ll cover your protein needs without overthinking it.