• Lower cholesterol: Soy has been associated with a significant reduction of total cholesterol levels in the blood, including low-density lipoprotein cholesterol (LDL, also known as the “bad cholesterol”) and triglycerides. Studies show that when soy proteins replace foods high in saturated fat, trans-saturated fats, and cholesterol, there is a correlation with lower total cholesterol levels.
• Reduce the risk of heart disease: Soy’s fiber, polyunsaturated fats, and plant proteins have been shown to lower heart disease risk. The isoflavones found in soy can improve your heart health by keeping your arteries and blood vessels clean and clear — they may increase nitric oxide secretion by endothelial cells, (the cells that line blood vessels) causing smooth muscle cells in the vessel wall to relax. This allows for blood to flow more easily, thereby decreasing heart attack risk or clotting. Recent research has also shown that soy may have an impact on a biomarker called e-selectin, which is capable of increasing the risk of heart disease. E-selectin is a protein that can be found in endothelial cells of individuals with heart disease. This protein makes the cells sticky and attractive to inflammatory cells that can damage the vessel. Isoflavones seem to play a role in reducing the amount of e-selectin, thereby decreasing inflammation and maintaining the smooth lining of the vessel walls.
• Regulate leptin (the “satiety hormone”): In adults with metabolic diseases such as obesity, insulin resistance, or type II diabetes mellitus, soy protein may play a role in reducing elevated leptin levels (another biomarker that can influence heart disease risk). Usually, leptin rises after a meal and signals to the brain that you are full or satiated. However, in insulin-resistant or obese adults, leptin levels are chronically elevated and lose effectiveness on the brain. High leptin levels don’t prevent hunger, and instead begin to affect other aspects of health, such as immune function, and cardiovascular health, including high blood pressure. In adults with metabolic disorders, eating soy may help lower leptin levels to a healthier range.