What Can Cause Rapid Weight Loss in a Man?

Electronic scale

As an Amazon Associate, Modded gets commissions for purchases made through links in this post.

When the scale shows fewer pounds, some people see this as a good sign. Weight loss can be a significant achievement in your fitness journey. However, it’s not always welcome. Your lifestyle might not change, but your weight could do so unexpectedly. What can cause rapid weight loss in a man? We’ll discuss the most common factors and what you can do for treatment. 

What Can Cause Rapid Weight Loss in a Man?

Person stands on a scale to measure their weight.

Rapid weight loss in a man can cause concern for you, your partner and everybody else in your family. So, what typically leads to this issue? Here are six reasons explaining why you’ve rapidly lost weight. 

1. Overactive Thyroid

Overactive thyroid (or hyperthyroidism) occurs when this gland overproduces your thyroid hormone. What causes hyperthyroidism? Graves’ disease is a common reason why you may have an overactive thyroid. Experts say about 1% of the U.S. population (nearly 3.3 million people) have Graves’ Disease. 

Hyperthyroidism can cause rapid weight loss in a man by increasing your metabolism. Your thyroid gland controls these chemical reactions, so an overactive thyroid makes you burn calories faster than average. Thus, your typical daily diet won’t keep up with your body’s activity. 

2. Type 1 Diabetes

A blood glucose monitor sits on an outside table.

Type 1 diabetes is another explanation for why you’ve rapidly lost weight. This disease is most common in children, thus its former name, juvenile diabetes. However, you can develop type 1 diabetes at any point in your life. Type 1 diabetes affects about 5.7% of American adults with diabetes, so it’s less common but still prevalent in society. 

Type 1 diabetes can cause rapid weight loss by compromising your pancreas. People with this disease consume sugar but can’t use it to energize their bodies. Thus, the sugar exits your body when you urinate. Your body then turns to your fat and muscles for its energy, which causes you to lose weight rapidly. Keep your grocery list full of snacks for those with diabetes to ensure your health stays on point. 

3. Cancer

Man looks into a microscope to study thin material.

The last word you want to hear from a doctor is cancer. Cancer occurs in your body when various diseases come together and spur abnormal cell growth. These cells invade other parts of your body and create lumps, bleeding, weight loss and other symptoms. The American Cancer Society estimated about 1.9 million people received a cancer diagnosis in 2021. 

Weight loss can be a symptom of several forms of cancer, so pinpointing the correct one is vital. Some common cancers causing rapid weight loss may include: 

  • Stomach
  • Pancreatic
  • Liver
  • Small bowel
  • Esophagus 

Generally, cancer causes weight loss by making you lose your appetite and wasting your muscles. Other problems arise if you have tumors growing in your body. This excessive tissue growth causes your body to expend more energy, thus burning more calories. 

4. Depression

Some diseases and disorders causing rapid weight loss are more tangible than others. For example, depression is a mental state you can’t see with a CT scan. Unfortunately, depression affects friends, loved ones and everyone else around us. Research shows major depressive disorder affects about 21 million Americans, or 8% of the population, making it one of the most common mental illnesses. 

Depression causes rapid weight loss by altering your appetite and eating habits. This mental state can deprive your energy and make you not want to eat or prepare very little food. For example, instead of eating the steak dinner you planned, you eat a few pieces of fruit. Depression may cause you to miss meals entirely, depriving your body of the necessary calories to maintain your weight. 

5. Irritable Bowel Syndrome (IBS)

IBS is a daily hindrance if you’re unlucky enough to have it. Whether at the bar or home watching football, you could suddenly feel abdominal cramps. Having a restroom nearby is essential to manage your bowels. Research estimates about 10% of the American population has IBS, with many affected under 50. 

IBS isn’t as direct with weight loss — but its symptoms can make you shed pounds even if you don’t want to. For example, you may find some of your favorite foods to be IBS triggers. Therefore, you reduce your frequency of eating them. Some IBS-worsening foods include caffeine, chocolate, dairy and fried foods. Suddenly, going to the state fair is much more complicated!

6. Rheumatoid Arthritis

When you think about arthritis patients, you may imagine older adults as their bone health weakens. However, you don’t have to be in your golden years to have rheumatoid arthritis (RA). RA could develop as young as 30 or begin in your later years. You might not associate arthritis with weight loss, but there is an association.

RA negatively affects your body by damaging your joints and wasting your muscles. Therefore, you’ll likely have inflamed joints, causing an increased metabolism. Now, it takes more food to keep your body weight up. Some severe versions of RA, such as rheumatoid cachexia, are primarily known for causing weight loss.

How Men Can Treat Rapid Weight Loss

If you notice fewer pounds on the scale, seeing your primary care physician is an essential first step. Record all your symptoms and how they affect your daily life to give your doctor an idea of what you’re going through. Plus, you may be able to narrow down the options for yourself and answer why you’re rapidly losing weight. 

For example, you may have Graves’ disease but have not yet received a diagnosis. People with Graves’ Disease could have a rapid heartbeat, an oversized thyroid, shaky hands or bulging eyes. If you see symptoms, alert a health care professional immediately. Early diagnosis of any disease is vital for your long-term health. You’ll have a better idea of what has caused rapid weight loss in your body.

What Can Cause Rapid Weight Loss in a Man? Myriad Health Issues

Losing weight is a desired outcome for some and unwanted for others. You may have noticed changes in your body and the numbers on the scale despite not changing your exercise and dietary habits. When this occurs, seeing your primary care physician is vital. They’ll educate you on what can cause rapid weight loss in a man and what is affecting you. It could be one of these six diseases or another explanation.

Stay up to date with the latest by subscribing to Modded Minute.