In the acute phase of nephritis, patients are generally required to have a light diet and minimize their protein intake, with their protein intake level being about 80% of that of a normal person. They should primarily consume animal-based proteins, which should account for more than 50% of their intake. This principle is called a high-quality, low-protein diet. Therefore, overall, patients with acute nephritis can eat beef, as it is considered a high-quality protein. However, the amount ingested needs to be limited. The intake of beef should be calculated based on the patient's body weight, with every 100 grams of beef containing 20 grams of protein. The total daily protein intake for patients should be 0.6 to 0.8 grams per kilogram of body weight, including both animal and plant proteins. Patients can use the aforementioned data to calculate how much beef they can eat.