Option D unit D7 Antioxidants (HL)

• A free radical is a particle that possesses at least one unpaired electron • Free radicals are produced in the body as a by product of normal cellular function Free radicals in the body examples: * Superoxide * Hydroxyl * Nitric oxide

• Can cause damage by removing electrons from parts of the cell in order to create paired electrons in their own structures Free radicals can: * Remove electrons from cell and mitochondria membranes * Remove electrons from molecules such as enzymes and DNA, thereby impairing their function

Role of antioxidants in the body: Can prevent or limit the damaging effects of free radicals by turning them into substances that are far less reactive Where they come from: * Vitamin A,C, E are antioxidants * Some minerals as well * Foods that contain antioxidants: berries red grapes, kale, broccoli and tea

• Free radicals are produced as a by product of normal cell function, and cells produce natural antioxidants to counteract them Exhaustive exercise: ex. running marathon, * Generates high levels of free radicals that cannot be controlled - damage to cells may occur = oxidative stress Training at sub max levels: * Reduces the build up of free radicals

• No consistent evidence that these supplements reduce oxidative stress or have a positive impact on training or performance unless a pre-existing dietary deficiency exists • Excess intake (RDI) may have detrimental effects on the body • A lack of adequate regulation of the supplement industry means that some products are poorly formulated and may even contain banned substances

• Useful if dietary deficiency • Natural antioxidants do remove free radicals so there is a potential link for supplementation