Beef vs lamb: which has more protein?

Here lean broiled sirloin meets broiled ground lamb, and the gap is mostly fat. Per 4 oz (113 g) the sirloin has about 35 g of protein and 2.5 g of saturated fat, the ground lamb 28 g and 9.2 g. Iron is close, 2.2 mg against 2.0 mg.

WHO counts both as red meat, which its cancer agency rates as probably carcinogenic. In pooled observational studies beef was tied to 30% more colorectal cancer, and lamb weakly to 11% more, from only 6 studies. Across 36 randomized trials, plant protein lowered LDL cholesterol more than red meat did.

Both are mammal meat, so a mammalian meat allergy can bring anaphylaxis one to several hours after either. Cook steaks, chops and roasts of both to 145 °F (63 °C) with a 3-minute rest, and beef burgers to 160 °F (71 °C). FSIS puts sausages made with ground lamb at 160 °F too. Our cards hold no figure for plain ground lamb.

CDC names undercooked lamb as one way Toxoplasma spreads, and a new infection around pregnancy can harm the unborn child. Case-control studies tie undercooked sheep meat and beef to higher odds of infection, and their authors advise pregnant women to avoid both.

If saturated fat matters, the sirloin here has under a third of the ground lamb's.

Evidence behind this note

1. Level E WHO places red meat, which by its own definition includes lamb, in IARC Group 2A, probably carcinogenic to humans. WHO, Cancer: Carcinogenicity of the consumption of red meat and processed meat
2. Level C Pooled cohorts put beef eaters at about a third higher colorectal cancer risk, and the estimate shrank when studies accounted for exercise. J Gastrointest Cancer, 2025
3. Level C Lamb was tied to an 11% higher colorectal cancer risk (RR 1.11, 95% CI 1.02 to 1.21) in a 2025 meta-analysis, and only 6 of its 27 studies measured lamb at all. J Gastrointest Cancer, 2025
4. Level A Across 36 randomized trials, replacing red meat with plant protein sources lowered LDL cholesterol by 7.3 mg/dL (0.19 mmol/L) (95 percent credible interval 0.03 to 0.36) and total cholesterol by 5.4 mg/dL (0.14 mmol/L), while the certainty of evidence was rated very low to low. Clin Nutr, 2025
5. Level E A US gastroenterology practice update warns that the same allergy can cause anaphylaxis one to several hours after mammalian meat, which is why it is missed. Clin Gastroenterol Hepatol, 2023
6. Level E USDA FSIS advises cooking raw beef and lamb steaks, chops and roasts to at least 145 °F (63 °C) and letting the meat rest for at least three minutes before carving or eating. USDA FSIS, Doneness Versus Safety
7. Level E USDA FSIS sets 145 °F (63 °C) plus a three-minute rest for raw beef and pork steaks, chops and roasts, and 160 °F (71 °C) for hamburger, measured with a food thermometer, since ground beef can brown before it is safe. USDA FSIS, Doneness Versus Safety
8. Level E CDC names eating contaminated undercooked meat, with lamb as one of its examples, as a way Toxoplasma spreads. A woman newly infected during or just before pregnancy can pass the parasite to her unborn child, who can have severe health issues even if she has no symptoms. US CDC, Toxoplasmosis: Causes and How It Spreads
9. Level C Across case-control studies, eating raw or undercooked sheep meat carried odds of acute toxoplasma infection of 3.85, and the authors advise at-risk groups, including pregnant women, to avoid it. Crit Rev Food Sci Nutr, 2018
10. Level E USDA FSIS says uncooked sausages made with ground beef, pork, lamb or veal should be cooked to 160 °F (71 °C), and those made with ground turkey or chicken to 165 °F (74 °C). USDA FSIS, Sausages and Food Safety

Written from the studies and agency guidance we hold for both foods, reviewed by the Bioma editorial system. How we verify.

Read more about these foods

• Beef and lamb: the answer depends on what replaces them
• Beef: who paid for the study predicts what it found
• Lamb: how the animal was fed shows up in your blood

Rankings and guides

• Which foods are highest in protein?
• Which foods give the most protein for the fewest calories?
• How much protein do you need per day?
• Protein: what it does and how much you need
• Protein: top food sources and Daily Value

More comparisons

• Beef vs pork
• Beef vs chicken
• Beef vs veal
• Beef vs mutton
• Beef vs shrimp
• Beef vs ground turkey
• Lamb vs chicken
• Lamb vs goat

• Beef: USDA FoodData Central, Beef, top sirloin, steak, separable lean only, trimmed to 0" fat, all grades, cooked, broiled, FDC ID 168634 · all forms of beef
• Lamb: USDA FoodData Central, Lamb, ground, cooked, broiled, FDC ID 172544 · all forms of lamb

Each food is one USDA entry, chosen as it is usually eaten. Other cuts, brands and preparations differ, and the links show them. % DV uses FDA Daily Values for adults. How we verify.