Thursday, March 28, 2013

Allergies and Cancer


Allergies

Sometimes the immune system overreacts to a particular substance called an allergen, producing an allergy. This may result from eating certain foods, inhaling particles or exposure of the skin to chemicals. Common allergies include asthma, hay fever, urticaria, farmer’s lung, food allergies and contact dermatitis. Treatments include avoiding allergens and antihistamine drugs. In some cases anaphylactic shock the body reacts so violently to an allergen, such as a wasp sting, that without treatment the patient may die.

Cancer

The body’s tissue cells constantly divide and replace themselves. Some times “rouge” cells divide out of control to produce an abnormal tissue growth or malignant tumor. Diseases involving these tumors are called cancers. If untreated, cancer cells spread from the tumour via the blood stream to other parts of the body where they produce secondary tumours. Eventually, cancer cells overwhelm the body and the patient dies. The risk of developing a cancer may be inherited, or it may be increased by smoking, drinking alcohol or exposure to chemicals. Cancer affects around 25 percent of people in the western world at some point in their lives and is the second most common cause of death after heart disease. Different types of cancers do not occur with the same frequency worldwide. This uneven distribution points to the involvement of environmental factors- such as food intake, smoking or exposure to ultra violet light- as causes of cancer. For example, stomach cancer in Japan and Chile is believed to be related to diets high in salted and pickled food.