Soy and its supplements in combating malnutrition and lifestyle disorders
Sheenam Garg*, Ravinder Kumar Malik, Vaibhao Lule, Nancy Awasti
Dairy Microbiology Division, National Dairy Research Institute, Karnal (HR)-132001, India
J Innov Biol (2014) Volume 1, Issue 3: Pages: 126-131
Abstract: Malnutrition is one of the most devastating problems worldwide and is inextricably linked with poverty. Each individual requires a minimum amount of nutritious food to keep them healthy. When this minimum requirement is not met the human body becomes weak and susceptible to infection. Therefore, to recover from this problem it is very important to supplement the diet with protein and energy rich content. Soybean contains all the three essential macro-nutrients required for good nutrition which serves as an excellent complement to lysine-limited cereal protein. It is the cheapest legume having neutraceutical properties. The amino acid pattern of the soybean is similar to cow milk. Tempeh, a soy based product is another excellent example which can provide beneficial effects by combating malnutrition. Moreover, soy fortified foods can fill the gap between poverty and adequate nutrition. Hence soy products can be used to prevent malnutrition among vulnerable group of community.
Received: 14 May 2014
Accepted: 11 June 2014
Published: 03 July 2014
Dairy Microbiology Division, National Dairy Research Institute, Karnal (HR)-132001, India
Keywords: Soybean, Malnutrition, Supplements, Fortified Foods
Two major categories of PEM are Kwashiorkor and Marasmus. Both are different events during homologous dietary deficiencies. The symptomology of marasmus is thought to be the result of the extreme degree of adaptation of the body to a deficient diet. In this situation, essential organs and function are protected at the expense of fat and muscle tissue. Kwashiorkor results after the host can no longer adapt to the nutritional stress.
Malnutrition is a multidimensional problem that requires multi-sectorial interventions. It has been estimated that 178 million children are malnourished around the world. Whereas 40 per cent children are found under-nourished among them 6.4 percent are estimated severely malnourished in India. Hence supplementary feeding must be the additional nutrients which are providing for the optional growth and desirable change in health status. Supplementary foods must be based on the formulation of the required nutrients for the treating of malnutrition, return the child to physiological, immunological and biochemical normality.
The noticeable example to the supplement food is a well-known legume called Soybean. Soybean is referred as vegetarian meat due to its high quality amino acids profile. It is less expensive legume as well as oil seed due to excellence source of macronutrients and other biological properties. Hence, it is used for the formulation of high nutritious weaning and supplementary foods. Most of the studies (Deshpande et al. 2004) recommended that soybean can be used for the snacks food as well as weaning and supplementary food to combat the malnutrition and to maintain good health and nutritional status of pre-school children.
Key Importance of Soybean in Overcoming Chronic Malnutrition
Good health depends on the availability, affordability, and acceptability of the foods essential to a balanced diet, including legumes. A balanced diet is essential for good health and human development. Malnutrition is primarily a problem of poverty, but it is also influenced by social and cultural factors. Excess energy consumption resulting in obesity is an extreme result of malnourishment, as is under-nutrition and starvation.
Climatic changes are expected to increase the variability of agricultural production due to increasing incidence of extreme climatic events such as drought or floods. It is also expected to change the distribution of pests and diseases, further increasing the risk of crop failure. The strongest negative impact of climate change is expected to be in sub-Saharan Africa and to a lesser extent in South Asia resulting in reduction of projected crop yield and fall in crop net revenues. These regions are likely to be exposed to the highest degree of instability in food production due to climate change which gives rise to the problem of chronic undernourishment. Vegetable soybean (Glycine max (L.) Merrill) can be consumed as highly nutritious vegetables or grains and are well suited to smallholder production under adverse climatic conditions.
A recent Food and Agriculture Organization (FAO) review of future world food production (FAO, 2009) predicted that the world’s population will increase by a third, or 2.3 billion people, by 2050. Most of this growth will be in developing countries. To meet expected demand, global food production will need to increase by 70%, and in developing countries it will need to almost double. While cereal production will need to increase by a third to meet demands, the production of commodities that are more responsive to increases in income will have to increase even further. This is likely to include food legume crops (Kinsella, 1976) because a continued dietary deficit in protein, minerals,and vitamins may be a more important source of malnutrition in sub-Saharan Africa and South Asia than a lack of energy.
Grain legumes provide a third of the protein needs of humans and under subsistence conditions can provide twice this amount (Graham and Vance, 2003). On a dry weight basis, vegetable soybean seed has a protein and oil profile similar to grain soybean, but contains more provitamin A and vitamin C than grain soybean and other legumes (Table 1). Also, vegetable soybean or ‘‘edamame’’ is a high value special type of soybean with larger seed (30 g dry weight/100 seeds) than grain soybean (10–25 g dry weight/100 seeds). Vegetable soybean is easy to digest and has a sweet taste due to its sucrose content (8–12%, dry weight basis) (Yousif and Faid, 2014; Tsou and Hong, 1991). Vegetable soybean is well adapted to a range of African growing conditions and suitable for planting at a range of latitudes, suitable for small-holder garden production as well as commercial production, possess good tolerance to a range of pests and diseases, drought hardy and fast maturing, gives high yields of quality seed for human consumption and stover for animal feed, familiar to growers and consumers, and with traits preferred by consumers and traders such as appearance, taste, and nutritional value. Moreover, it is also an excellent source of isoflavones, which have health-promoting benefits in the prevention of diseases including osteoporosis, cardiovascular diseases, cancer, and postmenopausal syndrome (Sabanis et al. 2009; Young and Scrimshaw, 1979; Ishimi 2009; Keatinge et al. 2011; Thompson et al. 2005; Butler 2010; Hwang et al. 2009; Xiao, 2008). Therefore, legumes, in particular soybean, due to their high protein content can prevent the initiation of vicious circle of malnutrition.
Potential Health Benefits of Soybean
Soybeans have been proposed to be the active component responsible for the beneficial effects and appear to work in conjunction with the proteins to protect against cancer, cardiovascular disease, and osteoporosis. The beneficial effects of dietary soy are observed in both healthy, experimental animals and in healthy humans outlined in figure1.
Estrogenic and Anti-estrogenic Effect
Menopause -a mid-life problem associated with women arises due to the reduction in estrogen production. Soy consumption exerts small effects on hormones in both men and premenopausal women in a beneficial direction. The hormonal effects of soy in premenopausal women have centered mainly on the potential benefits of anti-estrogenic effects on estrogen-dependent cancers such as breast cancer. A pattern consistent with lowered risk of breast cancer would include a longer menstrual cycle, reduced estrogens, increased sex hormone-binding globulin (SHBG) and increased urinary excretion ratio of 2- to 16-hydroxy estrogens (Kurzer, 2002). The hormonal effects of soy consumption in men have addressed potential adverse as well as beneficial effects. Exposure to high levels of dietary estrogens could alter the hypothalamic-pituitary-gonadal axis in men in a similar manner to that of diethylstilbestrol (endocrine disruptor). However, the issue was resolved by subcutaneous exposure to very high levels of genistein, an isoflavone, which resulted in decreased serum and testicular testosterone and pituitary luteinizing hormone concentrations, and decreased prostate weight (Strauss et al. 1998).
One-third of all cancers are thought to be related to diet. A major protector against cancer appears to be a diet high in fibre, low in fat, with generous intake of vegetables and fruits rich in phytochemicals and antioxidants. Although soybeans have a number of phytochemicals but most of the data point toward the isoflavones (genestein and diadzein) as being responsible for the hypothesized anticancerous effects of soy (Holzbeierlein et al. 2005). Diadzein has been shown to inhibit the growth of HL-60 cells implanted in the subrenal capsules of mice (Weisburger, 1991). On the same hand; genistein has been shown to inhibit the metastatic activity of both breast (He & Chan, 2013) and prostate cancer (Holzbeierlein et al. 2005) cells independent of the effects on cell growth. The inhibitory action could be due to antioxidants in genistein or due to the inhibitory action of genistein on several enzymes involved in signal transduction (Banerjee et al. 2008) including tyrosine protein kinases, MAP kinase, and ribosomal S6 kinase. There has been some speculation that soy or isoflavones could be used in the treatment of existing tumors, either alone or in conjunction with conventional chemotherapeutic agents.
Atherosclerosis and Cardiovascular Disease
Soy foods constitute moderate amounts of unsaturated oil, which proves them to be a good choice for a heart-healthy diet. Soy-fibre supplementation has a modest hypocholesterolemic effect in animals and humans due to their protein or isoflavone content (Anderson et al. 1995). Soy foods have been shown to have beneficial impacts on the risk factors for cardiovascular diseases, including lowering liver or blood triglyceride, total and low density lipid (LDL) cholesterol levels, increasing high density lipid (HDL) cholesterol and the ratio of HDL/LDL cholesterol. Anti-atherogenic effects of dietary soy protein have been recognized for several decades, but only recently have been brought to the attention of the medical community. Recent studies in rhesus monkeys showed that soy-protein preparations containing isoflavones significantly improved cardiovascular risk factors, specifically plasma lipid and lipoprotein concentrations, but soy-protein preparations without isoflavones did not (Xiao, 2008).
Obesity has become a worldwide epidemic and its prevalence continues to increase at a rapid rate in various populations and across all ages. High-fibre foods, such as soybeans, deliver more bulk with less energy (Anderson& Moore, 2004). They take longer to eat and produce a feeling of fullness in the intestine. They may also influence satiety by altering concentrations of hormones such as cholecystokinin and insulin. Studies suggested that protein is more satiating than carbohydrate or fat (Barkeling et al. 1990). The observations of enhanced post-meal satiety associated with protein compared with other nutrients suggested that increasing legume-protein intake may have weight-loss benefits.
Type 2 diabetes is a looming problem worldwide. Soy foods offer benefits in the prevention of diabetes and in the clinical management of established diabetes. High-fibre and potentially, high-protein foods assist in weight loss and management, thereby exerting diabetes-preventive effects. Studies suggested that there is a significant inverse relation between total dietary fibre intake and risk of type-2 diabetes. Soybeans, in particular, have a low glycemic index therefore seem to have a protective role against diabetes by enhancing sensitivity to insulin and favorably affecting serum lipid concentrations (Wang et al. 2013).
Soy Protein Isolates in Combating Malnutrition
Protein isolates are refined form of protein containing the greater amount of protein with greater digestibility shows a lot of potential to combat the problem of malnutrition. It is widely produced from de-oiled cake of legumes such as peanuts, cowpeas, soybeans, etc. and animal sources like fish and milk by a combination of isoelectric and alkaline precipitation using H2SO4 and NaOH, followed by centrifugation to obtain the pure isolates which can further be dried to powdered form of about 90% protein (Garba and Kaur, 2014).
Soy protein isolate is a common isolate. It has high protein content of about 90%. It is made out of defatted soy meal by removing most of the fat and carbohydrates (Sipos, 2013). Soybean is crushed into oil and defatted meal. The meal is usually used as animal feed, while smaller amount is further processed into food ingredients including soy flour, protein concentrate, protein isolates and textured protein (Laurin, 2002). Soy protein isolate is usually combined with other food ingredients such as vitamins, minerals and flavour in preparation of soy protein shake powder (Sipos, 2013). Advance in food technology resulted in the development of a variety of soy product such as concentrates, isolate and extruded-expanded products, this consequently leads to increased utilization by technically developed regions of the world (Young and Scrimshaw, 1979).
Soy Fortified Foods – In Prevention of Malnourishment
Western food has changed the scenario of Indian lifestyle and mainly attracted the interest of youngsters which make them more prone to lifestyle diseases and malnourished state at quite an early age. However, the solution to this problem can be achieved by using fortified foods having great nutritional value. Isolates, especially soy proteins are being used to fortify all type of pasta products such as macaroni, spaghetti, to improve the nutritional value etc (Taylor et al. 2009; Seyam et al. 1983). Isolates from different legumes varied slightly in physiochemical and thermal properties. They are used as proteinaceous ingredients in many food products such as salad dressing, meat products and dessert. Moreover, protein isolates are the acceptable ingredients for dairy application due to their fine particle size and dispersibility.
The problem of poor flavour, mouth feel, texture, dryness and flavour associated with the use of soy flour and soy concentrate above 10% has been resolved by using soy isolate in meat loaves, sausage-type products for their emulsion-stabilizing effect, gelation, and moisture retention and improved effects on texture (Laurin et al. 2002). Soy protein is regarded as textured protein products use both in meat and vegetarian meat analogue industry and thus, has good water holding capability (Rubio-Tapia et al. 2009). It is often used as meat extenders in comminuted meat products such as patties, fillings, meat sauces, meat balls, etc.(Berk, 1992; Riaz, 2006). Such soy fortified foods can fulfill dual needs that, it can fulfill the craze of youngsters for western food and can prevent them from macronutrient and micronutrient deficiency, so called malnourishment.
Tempeh is a compact, sliceable cake of mold fermented soybean cotyledons is an indigenous fermented food that originated from the Japanese people in Indonesia, where it is most popular (Aderibigbe and Kolade, 2003). Tempeh is a health promoting food. It is rich in nutrients and active substances. It is the best source of vitamin B12 in vegetarian diets (Omosebi and Otunola, 2013). Tempeh is cholesterol free and it helps to lower total cholesterol level in the blood, thus decreasing the risk of cardiovascular diseases (Rudkowska, 2008). Tempeh is readily digestible compared to other leguminous foods and is tolerated by patients suffering from dysentery and nutritional oedema. Tempeh contains high quality protein, thus can be used to supplement protein-energy deficient diets (Aderibigbe et al. 2010). Moreover, tempeh flour can also be incorporated into the basic foods which can help to combat malnutrition. On whole it can be concluded that the consumption of soy based food products like soy ladoo, soy chakali and soy flakes chiwada can significantly increase the consumption of major nutrient like energy, protein and fat. These products can be used to combat protein calorie malnutrition among the pre-school children (Ghatge, 2013).
Soy foods, such as fortified soy milk and calcium-set tofu, are excellent sources of calcium and high quality protein and are free of saturated fat and cholesterol. Calcium carbonate fortified soy milk has the same calcium bioavailability as cow’s milk, although availability from tri-calcium phosphate-fortified soy milk is somewhat lower (Zhao et al. 2005). Finally, the addition of soy foods to women, infant and children (WIC) packages is important because it expands options for milk for women and children, allows for cultural food preferences, and provides more choices for vegetarians/vegans and lactose intolerant individuals (Ashley and Karen, 2014).
Soy Supplementation Combating Celiac Disease-Cause of Malnutrition
Celiac disease (CD) is likely an ancient disease. Celiac disease is a chronic disorder of the small intestine caused by exposure to gluten in the genetically predisposed individuals (Livingstone et al. 1993; Hamer, 2005). CD is not a rare disease; prevalence ranges from 0.3% to 3% (Hill et al. 2005). It is characterized by a strong immune response to certain amino acid sequences found in the prolamin fractions of wheat, barley, and rye, resulting in damage to the mucosa of the small intestine and leading to the malabsorption of nutrients, thus adversely affecting all systems of the body (Yousif and Faid, 2014). CD is not a benign disease; it can be associated with malnutrition, malabsorption, osteoporosis, liver disease, skin disease, mental health issues, and other health problems (Fig. 2). In addition, children with untreated celiac disease often suffer from short stature caused by malnutrition. Moreover, and of particular concern, undiagnosed CD is associated with a fourfold increased risk of death (Rubio-Tapia et al. 2009).
The gluten-free diet remains until now the only treatment for celiac disease (Sabanis et al. 2009). Gluten-free diet includes benefits such as the recovery of the villi of the small intestine and reduced risk of malignant complications (Seraphin and Mobarhan, 2002). However there are growing concerns over the nutritional adequacy of the gluten free dietary pattern because it is often characterized by an excessive consumption of energy, and a reduced intake of proteins and dietary fibre (Thompson, 2001; Thompson et al. 2005). In such situation, legumes (soybean, chickpea etc.) known as "a poor man’s meat" can fill the gap as its addition to cereal-based products could be a good alternative for increasing the intake of legumes. In addition, legume proteins are rich in lysine and deficient in sulphur containing amino acids, whereas cereal proteins are deficient in lysine, but have adequate amounts of sulphur amino acids (Minarro et al. 2012). Therefore, the combination of grain with legume proteins would provide better overall essential amino acid balance, helping to combat the world protein calorie malnutrition problem (Livingstone et al. 1993).
Nutrition plays an important role in individual’s life promoting growth and development. Improper nutrition results into the initiation of vicious circle of malnutrition which further leads to adverse effects. In this context, soy bean serves as an important source of nutritional components as well as polyphenolic compounds with potential health benefits. Fermented soy products have high nutritional quality. The association of soybeans consumption with reduced risk of malnutrition and chronic diseases could be an exceptionally cost effectual approach for improving health. Because of their nutritional and health promoting properties, the development of bean based functional foods products as well as nutraceuticals needs to be promoted.
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