Soya beans are obtained from soya (Glycine max), a leguminous plant which differs in several varieties, about 30: black, yellow, 84 cm high or 110, etc.

They are used in the food field as:

• Decorticated
  
  Decortication removes the bark and is carried out industrially by means of machines with carved discs that, turning in various directions, remove the tegument that is removed with air blows.
  
  
• Undecorated
  
  
• Integrals

           All that needs to be done is to establish whether it is natural soya or GM transgenic soya.

It's a rather controversial food.

On the one hand, some studies draw attention to isoflavones present in soy that help defend the cardiovascular system by regulating cellular and enzymatic functions in situations such as inflammation, thrombosis and atherosclerotic progression (1).

On the other hand, it is even assumed that it may cause damage, particularly the Alzheimer's disease, if ingested in the form of an industrial product. This study analyses the problem (2).

Infant formulae, so-called SIFs containing soybean meal, were introduced almost 100 years ago. This study analyses their safety (3).

With regard to the allergenicity of soybeans, an attempt was made to identify which proteins (representing 35-40% of the dry weight of soybeans) are at risk, in order to develop hypoallergenic soybean products for sensitive people (4).

The results of this study showed that feeding male rats with large amounts of soybeans could induce aggressive behaviour (5).

Soya beans studies

References___________________________________

(1) González Cañete N, Durán Agüero Soya Isoflavonas de soya y evidencias sobre la protección cardiovascular [Soya isoflavones and evidences on cardiovascular protection. Nutr Hosp. 2014 Jun 1;29(6):1271-82. Spanish. doi: 10.3305/nh.2014.29.6.7047. 

Abstract. Soya isoflavones represent a group of non-nutritive, bioactive compounds, of non-steroidal phenolic nature that are present in soy bean and derived foods. They share with other compounds the capacity of binding to estrogenic receptors from different cells and tissues so that they may act as phytoestrogens. The current interest in these compounds comes from the knowledge that in Asian populations with high levels of their consumption the prevalence of cancer and cardiovascular disease is lower, as compared to the Western countries populations. This cardiovascular benefit would be the result not only of the modulation of plasma lipids, which is a widely studied mechanism. This paper reviews the published evidence about the beneficial effects of soya isoflavones and the different mechanisms of action that would benefit cardiovascular health and that surpass the mechanisms traditionally approached such as the modulation of plasma lipids, and that implicate the regulation of cellular and enzymatic functions in situations such as inflammation, thrombosis, and atherosclerotic progression.

(2) Roccisano D, Henneberg M, Saniotis A. A possible cause of Alzheimer's dementia - industrial soy foods. Med Hypotheses. 2014 Mar;82(3):250-4. doi: 10.1016/j.mehy.2013.11.033. Epub 2013 Dec 7. PMID: 24440006.

(3) Vandenplas Y, Castrellon PG, Rivas R, Gutiérrez CJ, Garcia LD, Jimenez JE, Anzo A, Hegar B, Alarcon P. Safety of soya-based infant formulas in children. Br J Nutr. 2014 Apr 28;111(8):1340-60. doi: 10.1017/S0007114513003942. Epub 2014 Feb 10. PMID: 24507712.

Abstract. Soya-based infant formulas (SIF) containing soya flour were introduced almost 100 years ago. Modern soya formulas are used in allergy/intolerance to cows' milk-based formulas (CMF), post-infectious diarrhoea, lactose intolerance and galactosaemia, as a vegan human milk (HM) substitute, etc. The safety of SIF is still debated. In the present study, we reviewed the safety of SIF in relation to anthropometric growth, bone health (bone mineral content), immunity, cognition, and reproductive and endocrine functions. The present review includes cross-sectional, case-control, cohort studies or clinical trials that were carried out in children fed SIF compared with those fed other types of infant formulas and that measured safety. The databases that were searched included PubMed (1909 to July 2013), Embase (1988 to May 2013), LILACS (1990 to May 2011), ARTEMISA (13th edition, December 2012), Cochrane controlled trials register, Bandolier and DARE using the Cochrane methodology. Wherever possible, a meta-analysis was carried out. We found that the anthropometric patterns of children fed SIF were similar to those of children fed CMF or HM. Despite the high levels of phytates and aluminium in SIF, Hb, serum protein, Zn and Ca concentrations and bone mineral content were found to be similar to those of children fed CMF or HM. We also found the levels of genistein and daidzein to be higher in children fed SIF; however, we did not find strong evidence of a negative effect on reproductive and endocrine functions. Immune measurements and neurocognitive parameters were similar in all the feeding groups. In conclusion, modern SIF are evidence-based safety options to feed children requiring them. The patterns of growth, bone health and metabolic, reproductive, endocrine, immune and neurological functions are similar to those observed in children fed CMF or HM.

(4) Capriotti AL, Caruso G, Cavaliere C, Samperi R, Stampachiacchiere S, Zenezini Chiozzi R, Laganà A. Protein profile of mature soybean seeds and prepared soybean milk. J Agric Food Chem. 2014 Oct 8;62(40):9893-9. doi: 10.1021/jf5034152. Epub 2014 Sep 29. PMID: 25229310.

Abstrct. The soybean (Glycine max (L.) Merrill) is economically the most important bean in the world, providing a wide range of vegetable proteins. Soybean milk is a colloidal solution obtained as water extract from swelled and ground soybean seeds. Soybean proteins represent about 35-40% on a dry weight basis and they are receiving increasing attention with respect to their health effects. However, the soybean is a well-recognized allergenic food, and therefore, it is urgent to define its protein components responsible for the allergenicity in order to develop hypoallergenic soybean products for sensitive people. The main aim of this work was the characterization of seed and milk soybean proteome and their comparison in terms of protein content and specific proteins. Using a shotgun proteomics approach, 243 nonredundant proteins were identified in mature soybean seeds.

(5) Abdel-Aleem GA, Shafik NM, El-Magd MA, Mohamed DA. Soya bean rich diet is associated with adult male rat aggressive behavior: relation to RF amide-related peptide 3-aromatase-neuroestrogen pathway in the brain. Metab Brain Dis. 2019 Aug;34(4):1103-1115. doi: 10.1007/s11011-019-00431-2. 

Abstract. Relation between soya bean (SB) consumption and aggressive behavior has not been elucidated yet. Thus, this study was conducted to investigate the effect of large amount of SB consumption on adult male rats' aggressive behavior through investigating changes in the expression of gonadotropin-inhibitory hormone/ RF amide-related peptide 3 (GnIH/RFRP3), neuropeptide FF receptor, cytochrome P450, family 19, subfamily A, polypeptide 1 (Cyp19A1), estrogen receptors α and β and the levels of neuroestrogen, dopamine, glutamate and testosterone as well as aromatase activity in the brain. Adult male rats were divided into three equal groups: group I, control group, received standard diet; group II and group III received 25% and 50% SB of their standard diet contents, respectively, for 12 weeks. The obtained results showed that feeding male rats with large amount of SB could induce aggressive behavior in a dose dependant manner possibly through inhibition of brain GnIH/RFRP-aromatase-neuroestrogen pathway. These effects may be through decreasing aromatase activity, neuroestrogen concentration, Cyp19A1 and ER β mRNA levels and increasing ER α mRNA levels and immunostaining as well as testosterone, dopamine and glutamate levels in the brain. These findings also provide further support for the inhibitory role of RFRP3 on aggressive behavior of male rats. These data may open new avenues for the potential harmful effects of consumption large amounts of SB rich food on humans.