Soy protein is often substituted for animal protein since it is low in fat and cholesterol. In addition, it contains dietary fiber, minerals and vitamins. Most of soy's benefits are due to estrogen-like compounds called isoflavones. Research indicates that incorporating soy into your diet may lower your risk of heart disease.
Hypertension
Researchers from the School of Medicine of Zaragoa, Spain, investigated the impact of soy milk on blood pressure levels in women and men with mild to moderate hypertension, a risk factor for heart disease. Patients consumed 500mL of soy milk or cow's milk twice daily for three months. At the end of the study, which was published in the July 2002 issue of the "Journal of Nutrition," scientists discovered that the soy milk group experienced decreases in blood pressure compared with the cow milk group.
Cholesterol
High cholesterol levels can damage arteries and increase the risk for heart disease. Scientists from the Tulane University School of Public Health and Tropical Medicine reviewed the clinical studies regarding soy protein supplementation and lipid levels in subjects with or without high cholesterol levels. They reported in the March 2006 issue of the "American Journal of Cardiology," that subjects with or without high cholesterol levels consuming soy protein supplementation experienced a significant decrease in total cholesterol and LDL cholesterol levels. In addition, soy protein increased HDL cholesterol levels.
Homocysteine and C-Reactive Protein
Iowa State University researchers examined the effects of the soy component phytate and soy isoflavones on cardiovascular risk factors, including homocysteine and C-reactive protein, in postmenopausal women. They reported in the October 2006 issue of the "American Journal of Clinical Nutrition," that postmenopausal women consuming 40 g of soy protein rich in isoflavones and phytate for six weeks experienced reductions in homocysteine and C-reactive protein levels.
Caution
Although soy might reduce the risk for heart disease, individuals who are allergic and suffering from kidney disease should avoid its use. In addition, soy might decrease iodine levels in the body, thereby affecting thyroid function, according to the University of Maryland Medical Center.
References
- "Journal of Nutrition": Soy Milk Lowers Blood Pressure in Men and Women with Mild to Moderate Essential Hypertension; M. Rivas et al.; July 2002
- "American Journal of Cardiology": A Meta-Analysis of the Effect of Soy Protein Supplementation on Serum Lipids; K. Reynolds et al.; March 2006
- "American Journal of Clinical Nutrition": Effects of Soy Isoflavones and Phytate on Homocysteine, C-Reactive Protein, and Iron Status in Postmenopausal Women; L. N. Hanson et al.; October 2006
- University of Maryland Medical Center: Soy
