Weight gain and fatigue are common issues that many people experience.
These symptoms are often natural consequences of dealing with everyday stressors and a lack of sleep.
However, unexplained weight gain and fatigue can sometimes be symptoms of an underlying condition.
Verywell / Laura Porter
Because many diseases could produce these symptoms, it may be difficult to pinpoint the exact cause.
Verywell / Laura Porter
Hypothyroidism
Thethyroid glandcreates thyroid hormone that keeps the body running.
An underactive thyroid, orhypothyroidism, comes up whenever the thyroid gland fails to produce enough of these hormones.
As a result, your metabolism slows, leading to weight gain and fatigue.
Too much thyroid hormone can also lead to fatigue and greater appetite, translating to weight gain.
So following your healthcare provider’s instructions is extremely important while undergoing treatment.
Does Hyperthyroidism Cause Weight Gain?
It is more common with an overactive thyroid (hyperthyroid) to lose weight than gain it.
However, high levels of thyroid hormone can stimulate the appetite and cause weight gain.
Hashimoto’s Thyroiditis
Hashimoto’s thyroiditisis an autoimmune disease that causes fatigue and weight gain.
With this condition, the body makes antibodies that attack the cells in your thyroid.
The thyroid gland becomes irritated, inflamed, or scarred and can’t make enough thyroid hormone.
Other symptoms of Hashimoto’s thyroiditis include:
Treatment may include medication to treat an underactive thyroid.
Weight gain and difficulty losing weight are typical in people with PCOS.
Weight gain with PCOS is often the result ofinsulin resistance, which commonly co-occurs with PCOS.
Over time, the body begins to overproduce insulin to keep blood sugar levels stable.
This overproduction can lead to weight gain andtype 2 diabetes.
In addition to weight gain, people with PCOS may also experience fatigue.
People with depression often experience chronic fatigue.
People with depression may also experience appetite changes and have weight loss or gain unrelated to their eating behavior.
It also affects appetite and weight control.
Increased levels in serotonin may lead to weight gain.
Those with depression are much more likely to become obese than those who are not depressed.
They offer treatment referrals and information on local mental health resources such as support groups and community-based organizations.
If you are having suicidal thoughts, dial988to contact the988 Suicide & Crisis Lifelineand connect with a trained counselor.
If you or a loved one are in immediate danger, call911.
Insomnia
Insomniais a sleep disorder that makes falling or staying asleep difficult.
It can also lead to waking up too early.
When someone doesn’t get enough sleep because of insomnia, they naturally become tired and experience fatigue.
Multiple studies have shown a link between insomnia and weight gain andobesity.
ECS is a critical player in the brains appetite regulation and energy levels.
These levels occurred around the same time that they reported increased hunger and appetite.
They also consumed more and unhealthier snacks between meals.
It is one of the diagnostic criteria of major depressive disorder.
It is so common that 80% to 90% of people with depression have insomnia.
Menopause
Menopauseoccurs whenmenstrual periodsstop for a consecutive 12-month period.
It typically happens after age 45.
During this time, your body produces significantly lessestrogenand progesterone.
Weight Gain
Duringperimenopause, the period leading up to menopause, estrogen levels begin their decline.
Fatigue
Fatigue is common in those going through menopause.
That’s because estrogen and progesterone both play a role in sleep, among other things.
Estrogen metabolizes serotonin and other neurotransmitters (chemical messengers) that affect your sleep-wake cycle.
Estrogen helps keep your body temperature low at night and, therefore, is more conducive to restful sleep.
Your healthcare provider may recommend over-the-counter or prescriptionmedicationsto improve sleep during menopause.
Non-hormonal medications can help with depression and anxiety and relieve vaginal dryness.
When the body releases adrenocorticotropic hormone (ACTH) from thepituitary gland, it triggers cortisol production.
This excess cortisol sometimes results from a tumor in the pituitary gland.
Weight gain is often the first sign of this condition.
That’s because too much cortisol can change the amount and distribution of body fat.
People with Cushing’s disease also experience severe tiredness.
Your healthcare provider might also prescribe hormone-inhibiting drugs to reduce the body’s cortisol level.
However, not everyone with this condition will have fluid build-up.
This throw in of weight gain may be a sign of congestive heart failure.
CHF can also cause fatigue.
Other symptoms of CHF include:
Treatment for CHF focuses on alleviating symptoms and slowing further heart damage.
Typically, it involves lifestyle changes and medications to reduce fluid retention and improve heart function.
Cancer
Cancer and cancer treatments can cause fatigue and weight gain.
Hormonal therapy for breast, prostate, or ovarian cancers can cause weight gain.
Eating to quell nausea or stress eating can contribute to weight gain in some people with cancer as well.
Lymphedema, a build-up of fluid in the fatty tissues, is a side effect of many cancer medications.
This swelling can cause you to gain water weight.
Some cancers may also cause abdominal bloating, which will make your waistband feel tighter.
They can be brought on by hormones, sleep problems, mental health issues, and other health issues.
If you have unexplained weight gain and fatigue, see your healthcare provider for a proper diagnosis and treatment.
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