The Free Radical Theory suggests that aging and various diseases are caused by damage from free radicals, which are unstable molecules that can harm cells. These free radicals are produced naturally in the body during processes like metabolism, but they can also come from external sources such as pollution, radiation, and smoking. Over time, the accumulation of this damage can lead to cellular dysfunction and contribute to aging. Antioxidants are substances that can neutralize free radicals, potentially reducing their harmful effects. Foods rich in antioxidants, such as fruits and vegetables, may help protect the body from oxidative stress. This theory has influenced research in areas like nutrition, aging, and disease prevention.