Losing a few pounds may seem like a bonus. But if it’s unexpected weight loss that came out of nowhere, it could signal an underlying health issue. Research suggests around 40% of people with cancer experience unexpected weight loss when they’re first diagnosed.1 That’s how critical sudden weight loss can be.
If you’ve noticed your clothes getting looser or the numbers on the scale dropping quickly, it’s important to know why it’s happening. So, let’s understand what causes sudden weight loss and what you can do about it.
What Causes Sudden Weight Loss?
Unintentional weight loss usually means you’re losing fat, muscle mass, or body fluids without changing your diet or activity level. This can occur due to many factors, including:
1. Thyroid Problems
An overactive thyroid (hyperthyroidism) speeds up your metabolism, causing rapid calorie burn. Symptoms often include:
- Anxiety
- Rapid heartbeat
- Sweating
- Trouble sleeping
2. Diabetes
In uncontrolled diabetes, especially type 1, your body can’t use glucose properly and starts burning fat and muscle for energy, leading to weight loss. Here are the signs to watch for:
- Frequent urination
- Excessive thirst
- Blurry vision
- Fatigue
3. Digestive Disorders
Conditions like celiac disease, Crohn’s disease, or ulcerative colitis affect how your body absorbs nutrients, leading to weight loss despite a normal or increased appetite. Other symptoms include:
- Stomach pain
- Diarrhea
- Bloating
4. Cancer
Many types of cancer can cause weight loss, often in the early stages. Other possible red flags are:
- Persistent fatigue
- Lumps or swelling
- Changes in bowel or bladder habits
5. Infections
Chronic infections such as tuberculosis, HIV/AIDS, or parasitic diseases can lead to significant weight loss by disrupting nutrient absorption or increasing metabolic demands. Alongside weight loss, you may also have:
- Fever
- Night sweats
- Fatigue
6. Malnutrition or Poor Diet
Sometimes, weight loss is as simple as not eating enough calories, either due to poor food choices, loss of appetite, or difficulty affording or accessing food.
7. Medications
Some medications for chemotherapy, thyroid conditions, depression, or diabetes can cause weight loss as a side effect.
8. Heart Failure or Chronic Illness
Chronic illnesses like congestive heart failure, pulmonary diseases, or kidney diseases can cause changes in appetite and metabolism that result in weight loss.
9. Depression and Mental Health Issues
Loss of appetite and disinterest in food are common symptoms of depression and anxiety. These can lead to unhealthy, rapid weight loss.
When Should You Be Concerned About Sudden Weight Loss?
- A general rule of thumb: if you’ve lost more than 5% of your body weight in 6–12 months without trying (for example, 10 pounds if you weigh 200), it’s time to speak with a doctor.
- Accompanying symptoms like fatigue, fever, changes in bowel habits, or persistent cough should also raise red flags.
What to Do If You’re Losing Weight Suddenly
Now that you know what causes sudden weight loss, it’s time to do something about it. Here’s what you should do:
1. Track Your Weight and Symptoms
Note when the weight loss began, how much you’ve lost, and any other changes like fatigue, appetite, or mood swings.
2. See a Healthcare Professional
Don’t ignore sudden weight changes. A doctor can order tests (bloodwork, imaging, etc.) to pinpoint the cause.
3. Discuss Your Diet and Lifestyle
Sometimes, a dietitian or doctor can spot nutritional imbalances or eating patterns that may be causing the issue.
4. Treat the Underlying Cause
Most importantly, addressing the root problem, whether it’s a thyroid disorder, infection, or emotional issue, is key to stopping unhealthy weight loss.
Sudden Weight Loss Needs Immediate Attention
If you notice your clothes are getting looser or the numbers on the scale dropping quickly, head to the Silverlake ER. We have little to no wait timing. You need no appointment and you won’t have to stand in line.
With on-site diagnostic imaging, we can quickly find out what causes sudden weight loss and start treatment right away. Early intervention can help catch serious conditions before they progress and get you back to feeling your best.
FAQs
1. How much weight loss is considered alarming?
Losing more than 5% of your body weight in 6–12 months without trying (e.g., 7–10 pounds for a 150-pound person) is considered significant and worth investigating.
2. Can stress cause weight loss?
Yes, chronic stress can suppress appetite, increase metabolism, and disrupt digestion, leading to unintentional weight loss in some people.
3. Is weight loss always a sign of cancer?
Not necessarily. While sudden weight loss can be an early symptom of some cancers, it is often caused by more common conditions like thyroid issues, diabetes, or digestive problems. Always see a doctor for proper evaluation.
4. What blood tests are done for sudden weight loss?
Doctors may test for thyroid function, blood sugar levels, complete blood count (CBC), liver and kidney function, inflammation markers, and infection indicators.
5. Should I be concerned if I’m eating the same but still losing weight?
Yes. If you haven’t changed your eating or activity levels but are losing weight, it could point to an underlying health issue and should be discussed with a healthcare provider.
