Textured soy protein, also known as TVP (Textured Vegetable Protein), is a manufactured soy product. The proper name is Total Soy Protein, or TSP, a more accurate description of the food product, contains a derivative of soybeans instead of actual vegetables.
TVP is produced from soy flour that is cooked under pressure, extruded and dried after the soybean oil has been extracted from the Soybean. The process involves separating the protein from the whole soybean to form a final product is a curd, which is then spray-dried at high temperatures. This results in a protein powder, which is put through a high-temperature and high-pressure process.
It has a long shelf life if stored properly, is affordable, nutritious as an excellent source of protein, calcium, magnesium and fiber, and is frequently used as a meat replacement due to its texture that resembles ground beef.
TVP’s role in keeping prostate cancer at bay
Prostate disease is an increasingly common medical condition among older men in many developed countries. It brings about a benign enlargement of the prostate, presenting urinary obstruction, discomfort and urinary problems. Both genetic and environmental factors have been implicated in prostate carcinogenesis. The male sex hormones namely testosterone, dihydrotestosterone (DHT) and androstanediol are considered as direct contributors to changes in the prostate gland. So at a basic level, prostate cancer is caused by changes in the DNA of a normal prostate cell.
Years of research has deduced that Prostate cancer is much more common in people with westernized diet. Therefore, certain dietary constituents may mediate prostate cancer growth. Soy beans and processed soyabean products contain isoflavones such as genistin and daidzin, phyto-oestrogens that possess weak oestrogenic properties. An in-vitro study has demonstrated that genistein inhibits the growth of prostate tumour cells.
The rates of prostate cancer increase among men who migrate from a country of low incidence rates to one with high incidence rates and this increase could be due to their adoption of a Western-style diet. Decreased intake of fat, increased dietary fibre and changes to a vegetarian diet have resulted in lower plasma androgen levels.
The consumption of animal products, especially some dairy products had been associated with an increased risk for prostate cancer. In contrast, prostate cancer rates are low in most Asian countries, where soybean products are frequently consumed, and it has been proposed that lower disease rates might be due, at least in part, to protective effects of TVP consumption and of other dietary and lifestyle factors.
TVP reducing the occurrence of breast cancer
Breast cancer begins when healthy cells in the breast change and grow out of control, forming a mass or sheet of cells called a tumor. A tumor can be cancerous or benign. A cancerous tumor is malignant, meaning it can grow and spread to other parts of the body. A benign tumor means the tumor can grow but will not spread. Breast cancer is the most frequently diagnosed female cancer, accounting for 29% of cancers in women. A diet rich in saturated fat is associated with a higher risk of estrogen- and progesterone-positive cancer. Estrogen is a class of hormones that the body can synthesize. They can enter cells and activate estrogen receptors to express certain genes, mainly related to sex.
Nutrition is one of the most modifiable aspects of people’s lifestyles and dietary choices can affect health and the risk of cancer. Overall, adhering to a healthy eating style may be associated with a significant reduction in the risk of breast cancer.
Busting the long standing myth of soy causing estrogen levels to rise.
TVP contains isoflavones, which act as phytoestrogens (essentially an imitation estrogen) in mammals. While they’re not the exact same as those estrogens found in human. Many studies have shown that soy may have cancer-preventive effects, particularly in the case of breast cancer. Years of research have gone on to show very clearly that soy does not affect estrogen or testosterone levels.
In summary, Textured Soy Protein offers multi-fold benefits to those across all ages and lifestyles. They improve diet, prevent certain types of cancer, improves health following menopause, reduce obesity, and offer a wider number of options for food diversity.
(The writer is Prof Shirani Ranasinghe, Senior Prof. in Biochemistry, Department of Biochemistry at the Faculty of Medicine – University of Peradeniya.)