Estrogens are group of hormones that refer to any substance either natural or synthetic that mimics the effects of the natural hormones. Hexestrol (HES) is included in synthetic estrogen-like substances, which are widely used in agriculture industries as hormonal growth promoters. Implantation or administration of hormonal growth promoters into cattle reportedly increased their feed efficiency and formation of lean muscle mass as well as milk production. However, the use of HES as growth promoters in animals’ production is confronted with many setbacks in the light of food safety. Many researches have reported a great potential for carcinogenic, mutagenic, teratogenic effects associated with their use. Consequently, HES, DES and other stilbenes are banned from the list of safe veterinary drugs that must be used for animal production.