Losing weight without intentionally changing your diet or exercise routine can have many causes, including thyroid disorders, digestive diseases, infections, depression, medication effects, and other medical conditions.
Cancer is only one possibility.
Nevertheless, significant unexplained weight loss should not simply be attributed to aging.
If weight continues to fall without an obvious explanation, a doctor can investigate the underlying cause.
6. Persistent Fatigue
Everyone becomes tired.
The warning sign is persistent or unusual fatigue that doesn't improve with adequate sleep and normal rest.
Cancer can sometimes cause fatigue through anemia, inflammation, metabolic changes, nutritional problems, bleeding, or the body's response to the disease.
But fatigue is also extremely common in people without cancer.
Poor sleep, stress, anemia, infections, thyroid problems, depression, medication side effects, and many other conditions can produce similar symptoms.
Persistent fatigue accompanied by other unexplained changes deserves medical attention.
7. Persistent Pain Without an Obvious Explanation
Pain is another symptom that can have countless causes.
Muscle injuries, arthritis, nerve problems, infections, and digestive conditions are far more common explanations than cancer.
However, pain that persists, progressively worsens, repeatedly wakes someone from sleep, or occurs together with other unexplained symptoms should be evaluated.
The location of the pain can sometimes provide useful clues, but pain alone cannot establish a cancer diagnosis.