Suya is a spicy meat skewer which is very popular. It may be served or sold along streets, in clubhouses, at picnics, parties, restaurants and within institutions. Suya is spiced with Yaji, a sauce that contains a mixture of spices like ginger, cloves, garlic, finely ground roasted groundnuts and ground pepper. It also contains monosodium glutamate and sometimes fine cornmeal.
Unfortunately, the production and consumption of Yaji are yet to be regulated although its complex combination of ingredients with active principles are potentially harmful when consumed in excess. This has been the basis for several scientific investigations aimed at determining the effect of Yaji on body organs.
Now, in a new study, scientists say that Yaji or its components can boost male fertility when consumed in moderate quantities without known condiments such as monosodium glutamate. The spice combination found in Yaji makes it a good flavouring ingredient for different foods and dishes, which explains its massive consumption in northern Nigeria.
The study, “A Comparative study on the effects of Yaji (Suya Meat sauce) and its spice constituents on the male reproductive profile of adult male Sprague Dawley rats” is in the latest edition of the journal, JBRA Assisted Reproduction.
The researchers had analyzed the potential effects of Yaji (suya meat sauce) and its composite spices on male fertility based on the state of the testes, the testosterone level in the blood and semen analysis parameters in 70 adult male Sprague Dawley rats with an average weight of 120 g. They were divided into two experimental study groups, respectively analysed for 28 and 56 days.
Semen analysis is a significant concept in infertility investigation of herbal compounds, drugs, or supplements taken as a measure to improve male fertility. The assessment of the changes in organ weight is an indicator to ascertain whether a tested substance or drug is toxic or therapeutic.
In this study, significant increases were seen in body and testis weight, blood’s testosterone level, sperm count and motility in the Yaji treated groups, in addition to significant increases in serum testosterone level, sperm counts, and sperm motility, and enhanced sperm production and proliferation of Leydig cells compared to the groups given isolated component spices. This also showed significant changes in testosterone and semen analysis when compared with the controlled groups.
Infertility may be caused due to low sperm count, impaired sperm motility, decreased testosterone levels, and abnormal sperm morphology.
They suggested that Yaji improved sperm production, supports seminiferous tubule cells and Leydig cell proliferation by means of synergistic reactions between spice constituents. Also, the increased level of testosterone may have been caused by the zinc and antioxidant properties present in Yaji and its constituent spices.
Yaji component spices have been documented in the treatment of male sexual dysfunction in Ayurvedic medicine. In fact, the Hausa male folks believe that some traditional or herbal aphrodisiacs such as Yaji, hakinmaye, and stimi help to enhance sexual performance, a belief that has made these spices highly consumed by men, most especially in the northern part of Nigeria and in Niger Republic, for their supposed effects on sexual appetite stimulation and stamina.
Scientific reports documented that the active compounds present in Yaji spices are potentially harmful when consumed in excess. The active compounds in Yaji include gingerol found in ginger, eugenol in cloves, capsaicin in red peppers, piperine in black pepper and allicin in garlic, each with documented adverse effects on the testis and male fertility when consumed in isolation.
Previously, researchers have reported that Yaji sauce has similar anti-fertility effects to those of cadmium, as it adversely interferes with male reproduction by impairing oxidative stress markers and the function and structures of the testis. Cadmium exposure can affect testes and induce processes leading to reduced sperm counts and impaired sperm motility.
In 2019, the researchers stated in the journal, Clinical Experimental Reproductive Medicine that Yaji caused a significant dose- and duration-dependent effect on semen quality, reproductive hormonal levels and structures in the testis.
In Nigeria, there is a growing concern about the excessive consumption of this mixture, which has been apportioned without a standard dosage or serving method and consumed mostly by men. A wide range of studies has reported deleterious effects of Yaji in major organs such as the pancreas, liver, kidneys, and brain.
Researchers, who assessed its effects on the kidney of adult Wistar rats, in the International Journal of Medicine and Health Profession Research showed that its excessive consumption is harmful to the kidney causing a very slight dysfunction of its cells and functioning.
Also, in the Asian Journal of Medical Sciences, experts said excessive consumption of Yaji is capable of inducing brain tissue damage and this is likely dependent upon the concentration of those ingredients with toxic potentials in a given measure of Yaji. They also suggested the need to regulate the production and consumption of Yaji.
@ Nigerian Tribune