Soy products refers to the soy isoflavones estrogen-like substances found in various plants and soy protein. To produce a reduction in cholesterol levels, both the isoflavones and soy protein apparently must be ingested.
A diet containing 25 grams of soy protein and 50 to 60 milligrams of soy isoflavones per day can reduce LDL cholesterol levels by about 10%.

