Selenium is a vital element for humans and animals, but many people lack enough of it. Adding selenium to plants and animals can boost human intake. Different methods like spraying plants and giving injections to animals have been used. This selenium boost can help plants handle stress and increase yield, while animals can grow healthier and fight off diseases better. However, preparing biofortified products can reduce selenium levels. Overall, adding selenium to plants and animals can help combat deficiencies and bring health benefits, but there are challenges to overcome.