Nutrients in meat: protein, iron and zinc vary by tissue

Protein is only one part of the comparison

Per 100 g cooked edible food, USDA SR Legacy lists roasted chicken breast at 31.02 g protein, 1.04 mg iron and 1 mg zinc. Roasted lean pork tenderloin supplies 26.17 g protein, 1.15 mg iron and 2.42 mg zinc. More protein does not automatically mean more of every mineral. [1]

Organs change the nutrient profile

Braised beef liver provides 29.08 g protein, 6.54 mg iron and 5.3 mg zinc per 100 g in this database. This is a tissue-specific record, not a stand-in for beef steak. These figures concern the amount present, not how much an individual absorbs, and do not establish a treatment for low iron or zinc. [1]

A hypothetical meal log

If the edible cooked chicken-breast portion is 85 g, its reference protein contribution is 26.367 g. Record the cooked edible amount rather than a raw, bone-in package weight. A sauce or breading adds a separate component, so a mixed dish needs more than the meat-only entry. [1]

Hypothetical example — compare specified portions using historical reference data
Cooked 85 g portion	Protein	Iron	Zinc
Chicken breast	26.367 g	0.884 mg	0.85 mg
Pork tenderloin	22.245 g	0.977 mg	2.057 mg
Beef liver	24.718 g	5.559 mg	4.505 mg

Nutrients in meat: protein, iron and zinc vary by tissue — original article outline diagram — Original editorial diagram of this article’s sections; no product photograph or clinical finding is depicted.

Sources for this article

USDA FoodData Central — SR Legacy April 2018 composition and portion tables
Source consulted: 2026-09-20. This is a reference resource, not a claim that we conducted the studies or tested a product.