“Beef” is not one nutrition profile. A trimmed lean roast and a well-marbled ribeye can come from the same animal and land in very different calorie ranges. Protein changes modestly across cooked cuts; fat is what drives most of the calorie spread.
The numbers also depend on how much visible fat is trimmed and whether the reference is raw or cooked. For a useful comparison, those conditions need to be kept as similar as possible.
Representative cooked beef values
| Per 3.5 oz (100 g) cooked | Calories | Protein | Fat | Iron |
|---|---|---|---|---|
| Very lean round/loin, visible fat trimmed | ~180–210 kcal | ~28–30 g | ~5–8 g | ~2–3 mg |
| Lean tenderloin | ~190–220 kcal | ~26–29 g | ~7–10 g | ~2–3 mg |
| 90% lean ground beef, cooked | ~220–250 kcal | ~26–28 g | ~11–13 g | ~2–3 mg |
| More marbled ribeye | ~280–330 kcal | ~24–27 g | ~20–25 g | ~2 mg |
These are representative ranges, not one label for every steak. Grade, trimming, cooking method, and doneness all move the numbers. The same cut name can appear with different values when one database entry includes more exterior fat than another.
Protein is fairly steady; fat is not
A lean cut with 29 g of protein and a fattier cut with 25 g differ by about 4 g of protein per 100 g. Fat can jump from 6 g to 22 g—a 16 g gap that represents about 144 calories from fat alone.
That is why two steaks of the same cooked weight can look like “the same amount of meat” and still have very different energy density. Protein remains high in both, but protein per calorie changes substantially.
A 5 oz portion makes the difference easier to see
A 5 oz cooked serving is about 142 g. At 200 calories per 100 g, that is roughly 284 calories and 40–43 g of protein. At 300 calories per 100 g, the same cooked weight is about 426 calories while protein may still sit around 34–38 g.
Both are protein-rich; the practical gap is mainly the roughly 140 extra calories in the fattier serving. If the sides, sauce, and cooking fat are the same, the cut itself becomes one of the biggest drivers of the meal’s energy difference.
Iron can stay near 2–3 mg even as fat rises from ~5–8 g to ~20–25 g
Many cooked cuts provide roughly 2–3 mg of iron per 100 g. Some of that is heme iron, which is generally absorbed more readily than nonheme iron from plant foods.
A lean cut with about 5–8 g fat per 3.5 oz (100 g) can still provide roughly 2–3 mg iron, similar to some marbled cuts carrying 20–25 g fat. That is a 12–20 g fat gap without a matching iron advantage. If the goal is iron with less energy, a lean cut can still do the job.
Beef also supplies vitamin B12 and zinc
Beef contributes vitamin B12, zinc, selenium, and several B vitamins. Exact amounts vary by cut, but they add to its nutrient density beyond protein alone.
Zinc is particularly notable in beef. That does not make beef mandatory, but it helps explain why two foods with similar protein can have different micronutrient profiles.
Raw and cooked values are not interchangeable
Cooking drives off water. That means 100 g of cooked beef is usually more concentrated in protein, fat, and minerals than 100 g of the same meat raw. The pan did not create protein; the denominator changed as water was lost.
Yield changes with cooking time, temperature, and doneness. For tracking a recipe or comparing nutrition, use a database entry that matches the state in which the meat is weighed: raw with raw or cooked with cooked.
Visible fat and cooking oil count too
Trimming 10 g of edible fat removes about 90 calories. Adding 10 g of oil during cooking adds about 90 calories, even if the steak itself is very lean.
A butter, cream, or cheese sauce can quickly overwhelm the natural calorie difference between cuts when the final dish is compared. The meat’s composition is only one part of the plate.
Choose the cut for the cooking job too
Lean steaks can work well for quick cooking when they are not overdone. Braises may benefit from cuts with more connective tissue and long cooking, which does not automatically mean choosing the fattiest option. For burgers, the labeled lean-to-fat percentage is often more useful than the generic word “beef.”
Matching the cut to the cooking method prevents the assumption that the lowest-fat cut is always best for every recipe. You can then adjust added fat and portion size around the result you want.
Bottom line
Ask which cut, not just whether it is beef. Lean cooked cuts commonly provide about 26–30 g of protein per 100 g with far less fat than a heavily marbled steak, while still supplying roughly 2–3 mg of iron per 100 g.
The cleanest comparison uses cooked portions of equal weight with similar trimming. That makes the pattern obvious: protein stays relatively steady while fat can multiply several-fold.
Sources
- USDA FoodData Central — Food composition and meat-cut data; values per 100 g.
- NIH Office of Dietary Supplements — Iron — Heme/nonheme iron and factors affecting absorption.