Maya had always been at a healthy weight, maintaining her routine of regular exercise and a balanced diet. But in the past few months, something strange began to happen. Despite keeping up with her usual eating habits, she noticed the number on the scale steadily dropping. At first, she thought it was stress or perhaps just a coincidence. But when her clothes started fitting looser and she began feeling more fatigued than usual, she decided to see a doctor. What she learned surprised her: unexplained weight loss is not always a sign of good health.Losing weight unintentionally may seem like a dream come true for many, but dietitian Christine Goukasian, senior dietitian at the UCLA Division of Clinical Nutrition warns in a news release that it could signal something more serious. "It’s not typical to have a noticeable drop in weight without changing how much you're eating, being more physically active, or trying to lose weight," she explains. "Unexplained weight loss is a red flag."While small fluctuations in weight—such as a pound or two—are normal and can be caused by hormonal changes or water retention, significant and persistent weight loss could indicate an underlying health issue. According to Goukasian, a loss of 10 pounds or at least 5% of your body weight within a 6- to 12-month period should raise concern.The risk is higher for older adults, particularly those living in community housing, where the likelihood of health problems contributing to unintended weight loss increases. As many as 2 in 10 older adults experience unexplained weight loss, with the figure rising to 6 in 10 among those in community settings.Could Sudden Weight Loss Lead to Cancer?Cancer is the number one cause of unexplained weight loss, accounting for over a third of cases. Goukasian highlights that weight loss can occur even in early-stage cancers of the colon, pancreas, and lungs, so it’s important to seek medical advice as soon as you notice significant weight changes.Can Gastrointestinal Issues cause Weight Loss?Gastrointestinal issues are another common cause, accounting for between 10% and 20% of unexpected weight loss. Conditions like chronic diarrhea, inflammatory bowel diseases, celiac disease, or even overuse of laxatives—often linked to eating disorders—can lead to substantial weight changes.How your Mental Health impacts your Weight?Mental health plays a crucial role too. Anxiety, depression, and stress can all reduce appetite or disrupt normal eating habits. "If you're not eating enough because of emotional distress, or missing meals due to sleep problems, you may experience weight loss," says Goukasian. Certain medications used to treat mental health conditions can also alter taste, smell, and appetite, further contributing to weight loss.Unexpected Causes of Unexplained Weight LossOther factors like dementia, thyroid disorders, diabetes, gum disease, and swallowing difficulties can make eating uncomfortable, leading to unintentional weight loss. Financial constraints or lack of access to nutritious food are also contributing factors.Importance of Seeking Medical HelpHowever, not all cases of unexplained weight loss are linked to life-threatening conditions. Many are manageable or treatable once diagnosed. That's why it’s crucial for anyone experiencing concerning weight loss to consult their healthcare provider. A thorough physical and mental health examination, along with blood tests and imaging, can help uncover the root cause."Identifying the cause of unexplained weight loss can take time and require multiple tests," Goukasian concludes. "But being proactive and paying attention to your body is the first step toward better health."Warning Signs to Watch ForUnexplained weight loss is often a red flag for underlying health issues. Identifying the signs early can make a crucial difference in treatment and recovery.Unintentional loss of 10+ pounds or 5% of body weight in 6-12 months.Fatigue or lack of energy despite adequate rest.Changes in appetite or a sudden disinterest in food.Digestive issues like chronic diarrhea or bloating.