Application of lemon juice on the site of old burns can help fade the scars, and since lemon is a cooling agent; it reduces the burning sensation on the skin when you currently have an irritating burn. Lemon has antiseptic and coagulant properties, so it can stop internal bleeding. Lemon is also a diuretic and can treat rheumatism and arthritis. It helps to flush out bacteria and toxins from the body. Lemon juice assists in relieving respiratory problems and breathing problems, such as its ability to soothe a person suffering from an asthma attack.