Substances added to food in order to improve or maintain its freshness, flavour, consistency, appearance, or safety is known as food additives. For thousands of years, food additives such as sulphur dioxide (found in wine), sugar (found in marmalade), and salt (found in dried fish or meats like bacon) have been utilised for preservation. This work aims to investigate the histopathological alterations in the testes and liver in rats eating food additive combinations (FAM) with fast green, glycine, and sodium nitrate, as well as Aphanizomenon flos-aquae's possible protective effects. Material and methods Group I served as control; Group II included rats exposed to food additives; Group III included rats exposed to food additives and treated with Aphanizomenon flos-aquae. Each group contained ten rats and the exposure period was thirty days. Results, the histological studies of the testes and liver revealed many alterations. The testes revealed focal degeneration, apoptosis, and necrosis of spermatogonia, spermatocytes and spermatids with the formation of syncytial cells in some affected tubules and complete arrest of spermatogenesis in testes cells. Meanwhile, apoptosis and focal hepatocyte vacuolation were displayed by liver cells. The hepatic sinusoids seemed to be considerably dilated, and vascular endothelia exhibited degenerative and necrotic changes. According to the current findings, Aphanizomenon flos-aquae can shield the liver and testes' histological structures from the damaging effects of food additive mixtures. Conclusion The administration of Aphanizomenon flos-aquae with the food additive mixture (FAM) attenuated the significant changes in the testicular and hepatic histological structures that resulted from the FAM treatment.