Foods containing soy are derived from the soybean plant. Besides offering protein to your diet, soy products may also contain isoflavones, which are estrogen-like components found in many plants. Soy products, such as tofu, soy beverages, soybean burgers, and soy nuts, already have an established reputation of being worthy of being included in your diet, since they offer a healthy alternative to animal protein. Soy also has gained a reputation over the years for lowering cholesterol levels.
Does Soy Have What It Takes To Lower Cholesterol?
When the connection between soy and cholesterol was first established, scientists found that there were two major components could potentially lower cholesterol: the soy protein itself and isoflavones. Human studies have looked at the ability of soy protein, isoflavones, and a combination of both components to assess the cholesterol-lowering ability of soy.
Soy protein and isoflavones used in these studies ranged between 25 to 135 grams a day of soy protein and 40 to 300 mg a day of isoflavones. With an average ingested amount of 50 grams, low-density lipoproteins (LDL) were only lowered by an average of 3 percent. High-density lipoproteins (HDL) and triglycerides do not appear to be affected by soy protein and/or isoflavones. Current research suggests that the soy protein, or some component within the soy protein, may be the cause of the lowered LDL cholesterol levels. Studies using a combination of soy protein and isoflavones show the most, although small degree of, cholesterol-lowering effect. Studies using isoflavones alone have resulted in minimal, if any, cholesterol-lowering ability.
The majority of the studies performed so far suggest that soy does work in lowering LDL cholesterol, but only by a small percentage. A potential problem with this is that if you chose to use soy protein to lower cholesterol, you would need to ingest a large amount of it. The average amount used in most of these studies was 50 grams, which is more than half of the recommended protein intake for one day. Additionally, one study found that individuals with high cholesterol levels benefited more from the cholesterol-lowering effects of soy than those with normal cholesterol levels. More studies need to be performed in order to establish this theory.
The Food and Drug Administration has recognized the healthy benefits that soy can provide. In 1999, the FDA released a statement that allowed the makers of soy products to carry a “heart-healthy” claim on their food labels. This was based upon the fact that soy products were low in saturated fat and current research that stated that 25 grams of soy could lower LDL cholesterol by 10 percent. Based upon research that has emerged since then, the FDA may need to examine its claim with regard to soy’s ability to lower cholesterol.
Should You Use Soy To Lower Your Cholesterol?
Despite the small decrease in cholesterol that they may provide, soy products are recommended as good replacements for animal fats, which are known for raising cholesterol levels. In addition to their ability to modestly lower LDL cholesterol, soy products are high in protein and fiber, and low in saturated fat, which are additional plusses to a heart-healthy food. If you are looking for ideas on how to include soy in your diet, try some of these healthy recipes and tips:
Sacks FM, A Lichtenstein, L Van Horn, W Harris, et al. Soy protein, isoflavones, and cardiovascular health: an American Heart Association science advisory for professionals from the nutrition committee. Circulation. 2006; 113:1034-1044.