Managing and controlling environmental temperature conditions using practical strategies is crucial to avoid the negative impacts of high environmental temperature, improving poultry production and welfare. High environmental temperature is one of the significant factors challenging poultry production during hot seasons or in tropical areas causing heat stress (HS). The detrimental effects of HS on broilers range from reduced growth performance to impaired poultry meat quality. HS impairs physiological responses caused by alteration in blood parameters, which could lead to impaired product quality by reducing moisture content and altering the production of antioxidant enzymes resulting in increased oxidative stress. There has been a focus on the use of nutritional supplements as a cost effective HS amelioration strategy, such as betaine and polyphenols. Supplementing broiler chicken’s diets with polyphenols aims to enhance growth performance via reduced levels of oxidative stress in tissues under HS conditions. Furthermore, using betaine as an osmolyte aims to protect tissues during osmotic stress conditions. The current review reveals that betaine and polyphenols are essential under crucial conditions such as HS to protect tissues from oxidative damage.