What It Means When You Experience Unexpected Weight Loss

Given our culture's obsession with diets, chances are you're constantly reading and hearing about the latest weight-loss methods and exercise routines that will help you keep your weight down.

But what if you are someone who is not actively trying to lose weight — is this cause for concern?

While it's natural for your weight to go up and down over your lifetime, if you lose 5% or more of your body weight over the course of a year, and you can't determine a clear reason for it, it could be time to consult with a medical professional (via NHS UK). There are a variety of reasons as to why you could be naturally losing weight without trying. Sometimes it could be the result of stress from a job or a difficult breakup. In time, your system will generally level out. But alternatively, a sudden loss in weight could also be due to a serious illness.

"It's not common to lose a significant amount of weight without an obvious reason," Anne Cappola, an endocrinologist and professor of medicine at the University of Pennsylvania, tells Prevention. "If you're losing weight and nothing's changed with your diet or activity, you need to worry about that a little bit," she states.

If you find you're continuously losing weight, one of the causes could be an over-active thyroid. Your thyroid manages your metabolism, and if your thyroid is overworking itself producing hormones, this could cause your weight to get out of whack. 

There are also certain types of cancer that can affect your digestive system. "If someone comes to me with unexplained weight loss, I'll check their stomach and colon and bowels for tumors or inflammation," Jamile Wakim-Fleming, a gastroenterologist at the Cleveland Clinic, tells Prevention. "I'll also look for tumors in the esophagus."  

Other possible reasons for unexplained weight loss could be related to one's mental health. For those experiencing depression, losing your desire to eat is a common occurrence. "In a lot of cases, the person doesn't even notice they're losing weight because they're mired in depression," Dr. Cappola explains.

While unexpected weight loss may be temporary and situational, there may also be potentially critical reasons behind why you're suddenly losing weight. If this is happening to you, and the issue does not correct itself, check in with your doctor for a thorough examination, proper diagnosis, and specific treatment instruction.