Dietary Supplements of Vitamins E, C, and β-Carotene to Reduce Oxidative Stress in Horses: An Overview

•Horses are animals that face various stress situations throughout their daily activities.•Oxidative stress is the excess generation of free radicals, causing damage to the horse's health.•Supplements of vitamin E, C, and β-carotene in the diet show beneficial effects on horses.•Vitamin E, C and β-carotene prevent diseases associated with the oxidative stress. Oxidative stress is the excess generation of free radicals and/or a decrease in the response of the antioxidant system. It is known to cause damage to the equine health by unbalancing the stable molecules. The dietary supplementation of vitamins E, C, and β-carotene cause beneficial effect on horses’ health. These supplements could transform free radicals into the stable radicals, thereby showing importance in the prevention of diseases associated with oxidative stress. Adding vitamins E, C, and β-carotene to the horses’ diets in stressful conditions could decrease the production of free radicals that cause inflammation and tissue damage, the typical characteristics that have been associated with oxidative stress. This review spotlights the available evidence of the benefits of dietary supplements of vitamins E, C, and β-carotene towards the reduction of oxidative stress in horses.