Yes, fatty cuts of meat are complete proteins. Regardless of their fat content, all cuts of meat (such as beef, pork, and lamb) contain all nine essential amino acids required by the body.

Here is a breakdown of how fat affects protein in meat:

Complete Protein Content: Both lean and fatty (marbled) cuts are considered complete proteins, containing sufficient levels of essential amino acids like leucine, which is critical for muscle repair.

Protein-to-Fat Ratio: While fatty cuts are complete proteins, they have a lower concentration of protein per gram compared to lean cuts because the fat takes up space that would otherwise be filled by muscle tissue (protein).

Nutrient Profile: Fatty cuts are often nutrient-dense, providing not just protein but also iron, zinc, and Vitamin B12, although they come with higher calories and saturated fat.

Examples: A 3-ounce serving of a fattier cut like ribeye contains about 17g of complete protein, whereas a leaner cut might offer more, but both are considered high-quality.

For maximum protein intake per calorie, leaner cuts are preferred, but all cuts of red meat provide the full spectrum of essential amino acids.