Surprise weight loss
At first, sliding more easily into your skinny jeans may come as a pleasant surprise. But losing 10 pounds or more for no clear reason – you haven’t, for instance, taken your fitness regimen up a notch, started a newly diligent diet, tamed your cravings by sleeping more or even lost your appetite due to stress – can be the first sign of cancer, according to the American Cancer Society. Cancers of the pancreas, esophagus, stomach and lung are most often linked to unexplained weight loss.