6. Weight Loss
For some people this might seem like an unexpected blessing, but it could be the opposite. Dropping five or 10 pounds without trying could be triggered by a thyroid problem – which is also something you should not ignore. But it could also be an early sign of cancer. Losing 10 pounds or more unexpectedly is definitely cause for concern and could be linked to cancer of the stomach, pancreas, esophagus, or lungs.
