A recently published study from the University of Pittsburgh shows how strongly animal protein in the diet contributes to the development of arteriosclerosis. In this study, a research group of biologists and biomedical scientists led by Xiangyu Zhang summarizes the results of various tests on humans, mice and macrophages.
The nutritional tests were conducted on 23 overweight but otherwise healthy human subjects and were intended to show how the body reacts to increased protein portions.
In the first test, 14 subjects drank a high-protein shake containing 500 calories and 50 percent protein after fasting for 12 hours. On another day, they were given a shake with a different composition, also containing 500 calories, but only 10 percent protein.
For the second test, nine subjects each ate two small meals of 450 kcal. One meal contained 16 grams, or 15 percent of calories, from protein, and the other 25 grams of protein, or 22 percent of calories.
After each meal, the researchers took blood from the test subjects, isolated immune cells from it and analyzed the composition of the amino acids that were in the blood after the meal.
Starting from a protein portion of 25 grams, the concentration of some amino acids in the subjects’ blood samples increased significantly, including isoleucine, valine, methionine, threonine, serine, arginine and leucine.
