Soy and Human Health

The Astonishing Functional Food: Soy Protein and Soy Constituents

Figure 1

Recent interest in the constituents of soybeans, particularly the isoflavones, has been explored to the status of a promising nutraceutical with potentially significant health benefits. The back bones of isoflavones in soy are genistein (4',5,7-trihydroxyisoflavone), daidzein (4',7-dihydroxyisoflavone) (See Figure 1) and their metabolites. In addition, soy products are a source of lignans, coumestans, saponins, plant sterols, phytates (inositol hexaphosphate), and protease inhibitors, all of which are also garnering attention for their health-promoting benefits.¹ Soy constituents have been shown to have estrogenic, anti-estrogenic, antiviral, anticarcinogenic, bacteriocidal, and antifungal effects. Isoflavones are antimutagenic, antioxidant, mild anti-inflammatory, antihypertensive, and antiproliferative effects.

Soy Protein and Coronary Heart Disease

Reduction of elevated blood LDL-cholesterol levels is given the highest priority in the prevention and treatment of atherosclerosis and CHD (Coronary Heart Disease). Therefore, it is not surprising that much of the research on soybean protein and CHD has centered on soy protein's ability to lower blood levels of LDL-cholesterol in animals and humans. Health professionals are taking a broader view in dealing with hypercholesterolemia as a major risk factor for CHD. Limiting concern to those people with diagnosed hypercholesterolemia may be too narrow an approach to such a widespread problem. It is estimated that 96 million adult Americans-52.1% of the adult population-have blood cholesterol levels of 200 mg/dL or higher, and that about 37.8 million adults-more than 20% of the population-have levels of 240 mg/dL or above.

Soy and Digestive Tract Health

Several studies have shown that soy protein may promote a healthy digestive tract from the mouth to the colon. Many EnerFlex customers report better digestive health. Digestive tract cancers are one of the most common causes of death among Americans, particularly colon cancer.

Soy Foods in Chronic Renal Disease

Renal disease is an important cause of morbidity and mortality in industrial and post-industrial societies. Over the last two decades, a steady rise in the longevity of the U.S. population has resulted in a parallel increment of prevalence of chronic renal disease. In 1995, 275,000 U.S. citizens were on renal replacement therapy (dialysis or transplantation) at a cost to the nation of $13 billion per year and the projections are that by the year 2010 there will be 1.1 million U.S. citizens on RRT at a cost exceeding $50 billion per year.

How Can Soy Help Diabetes?

Over 16 million Americans have Diabetes, an illness characterized by "high blood sugar" levels (hyperglycemia). Hyperglycemia can lead to premature heart disease, kidney failure, blindness, nerve damage and poor-healing ulcers on the lower extremities. Many doctors are now recommending soy for diabetics because it addresses 5 major concerns associated with the disease.

Soy Protein Enhances Energy, Stamina and Sport Performance

We all could use more energy and vitality. Whether you need more energy to keep up with your children/grandchildren, or to win an Olympic Gold Medal, soy can help. Key nutritional qualities of soy protein have been identified that improve energy, stamina and sports performance, particularly, lean muscle mass, strength, endurance and recovery times. These qualities are highlighted here.

Soy and Cancers - Some recent clinical reviews

Thyroid Cancer, Prostate Cancer, Breast Cancer...

Soy and Breast Cancer

According to the United States National Cancer Institute, women who live to be 90 years old have a 1 in 8 risk of being diagnosed with breast cancer. Breast cancer is expected to be the most frequently diagnosed non-skin malignancy in U.S. women, second to lung cancer.

Soy and Menopausal Symptoms

Menopause is part of the natural aging process for women. Decreasing levels of estrogen production by the ovaries as women age cause many unpleasant symptoms, most commonly hot flashes, night sweats, mood swings, weight gain and vaginal dryness.

Soy and Pre-Menstrual Syndromes

Menstrual cramps. Irritability. Mood swings. Fatigue. Headaches. Food cravings. Bloating. Many women are all too familiar with these recurring monthly symptoms that can temporarily cripple their lives at worst, or simply make them miserable at best.

Soy and Bone Health

Human studies showed a bone-sparing effect of soy protein with isoflavones at 80-90 mg/d. In a recent study conducted was to evaluate the effect of 2 y of consumption of isoflavone-rich soymilk (100 mg/d), natural transdermal progesterone (25 mg/d), or both on bone mineral density in the lumbar spine and hip.

Losing Weight Healthily with Soy

More and more people face a struggle with their weight. In fact, despite a decade of infomercials pushing weight loss equipment and pills, Americans and people around the world are fatter than ever. Many Americans have resorted to dangerous ways of losing weight including risky prescription medications and dangerous herbal supplements.

Soy and Urological Cancer

In a meta-analysis of peer reviewed studies and reports from 1966-1998 by researchers at the West Virginia University School of Medicine revealed that a number of epidemiological studies support the use of dietary agents to protect against various urological forms of cancer, including the bladder, prostate and kidney. (1) A study also shows that isoflavones, such as genistein and daidzein, work synergistically to inhibit cancer growth and induce apotosis.