And most of the time, thats probably whats behind it.

Lets explore 13 surprising health conditions that can lead to weight changes.

Your thyroid is a small but mighty butterfly-shaped gland in your neck, according to theMayo Clinic.

a illustration of a foot scale

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Hypothyroidismhappens when your thyroid gland doesnt make enough of these key hormones.

This can result in a reduced metabolism that leads to weight gain.

PCOSis one of those gynecologic conditions that mayseemsimple but is actually quite complex.

Like we said, its complex.

Insomnia can smash into every aspect of your sleep like a wrecking ball.

For starters,your circadian rhythm impacts your metabolism, and insomnia can throw them both off.

Peptic ulcer disease is so awful you might cringe just reading about it.

National Library of Medicinesays.

This happens when your heart cant pump enough blood to meet your bodys needs, theU.S.

National Library of Medicineexplains.

Your abdomen may swell as well, (theMayo Clinicsays) says.

Blood and fluid can also back up into your lungs, leading to fatigue and shortness of breath.

Sure, sometimes theres a simple, non-concerning explanation for your weight loss.

If youre grappling with this and other symptoms of persistent depressive disorder ordepression, thats definitely worth noticing.

This intestinal damage can also causediarrhea, fatigue, bloating, anemia, and more, theMayo Clinicsays.

This actually isnt a condition, its a collection of symptoms.

They may simply forget to eat, Dr. LePort says.

One of those disorders isCrohns disease.

The inflammation frequently spreads deep into the layers of the bowel tissue.

Unsurprisingly, if youre dealing with these symptoms, youre probably going to lose weight, Dr. LePort explains.

The weight loss occurs due to a portion of your adrenal glands called your cortex, theMayo Clinicexplains.

The cortex is the outer layer of these glands, and it produces a group of hormones called corticosteroids.

Corticosteroids include glucocorticoids, which influence your bodys ability to convert fuel from the food you eat into energy.

(As can the nausea, vomiting, and loss of appetite.)

Its normal for yourweight to fluctuatea bit from day to day, or even from morning to night.

But afluctuationthat keeps you in a general weight range is different from persistent weight gain or loss over time.

If thats what youre noticing, its time to head to a doctor.