According to the national health service, more than one person in three will develop some form of cancer during their lifetime. In the United Kingdom, the most common types of illness are breast cancer, lung cancer, prostate cancer and bowel cancer. There are over 200 different types of cancer in general, each of which will have different symptoms. Some symptoms overlap between the different types, however, one of which could be a sign of many different forms of the disease.
This symptom is involuntary weight loss. A sudden and obvious weight loss can occur after a stressful event, but it can also be a symptom of a serious illness.
According to the NHS, a persistent and unintentional weight loss of more than five percent of the weight of six to 1
Losing this weight can be a sign of malnutrition, in which a person's diet does not contain the right amount of nutrients and can also be a sign of cancer.
The NHS warns to pay particular attention to weight loss if it shows other symptoms such as fatigue, loss of appetite, a change in hygiene habits and an increase in disease or infection.
Unexplained weight loss may be a sign of cancer including the bowel cancer, prostate cancer and lung cancer, among others.
Other symptoms of bowel cancer include a persistent change in bowel habits, blood in the stool and pain in the stomach and swelling caused by eating.
the need t or go to the bathroom more often, with softer stools and with abdominal pain.
When unexplained weight loss is related to prostate cancer, it is usually a sign that cancer has spread to other parts of the body.
Prostate cancer includes the need to pee more frequently, often during the night, the need to run in the bathroom, the weak flow and the tension during the pee.
Difficulty starting to pee, blood in the urine or semen and feeling that the bladder has not emptied are also symptoms.
In addition to involuntary weight loss, other signs of prostate cancer are advanced include pain in the bones, back and testicles and loss of appetite.
Other symptoms of lung cancer include a persistent cough which worsens, persistent chest infections, cough with blood and persistent dyspnea.  Pain or pain during breathing or coughing, persistent fatigue or lack of energy and loss of appetite are also symptoms of lung cancer.  "It is normal to lose a significant amount of weight after the stress of changing work, divorce, redundancy or mourning," the NHS said.
"Weight often returns to normal when you start to feel happier after you have had time to cry or get used to change."
"You should see your family doctor if you have lost a lot of weight in the last two months that can not be explained by changes to your diet, exercise or stress, "said the NHS.