Written on June 18, 2023 by Theresa Vuskovich, DMD. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.
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Although lifestyle choices are often responsible for weight gain, you may have an underlying condition contributing to your weight gain. Conditions that may have weight gain as a symptom include hypothyroidism, Cushing's syndrome, polycystic ovary syndrome, depression, and insomnia.[1,2] This article discusses how these diseases and weight gain are related.
Hypothyroidism occurs when your thyroid hormone levels are low.[3,4] Your thyroid is a butter-fly-shaped gland responsible for controlling your metabolism, body temperature, heart rate, and digestion. The thyroid controls how your body functions by secreting hormones, which send messages to the rest of your body. Your thyroid secretes four hormones: thyroxine (T4), triiodothyronine (T3), reverse triiodothyronine (RT3), and calcitonin. T3 is primarily responsible for regulating metabolism.
The pituitary gland regulates the secretion of thyroid hormones by producing thyroid-stimulating hormones (TSH).[3,4] Your TSH levels are used to diagnose hypothyroidism. When your body is not producing enough thyroid hormones to function properly, your pituitary gland will produce more TSH, leading to elevated levels of TSH. Elevated levels of TSH and low levels of T3 are indicators of hypothyroidism.
Weight gain is a common symptom of hypothyroidism.[3,4] However, most weight gain from hypothyroidism is due to edema (swelling). Weight gain due to swelling typically ranges from 5 to 10 pounds. Another symptom of hypothyroidism is fatigue, which may lead to frequent snacking and gaining additional weight. Some other symptoms of hypothyroidism are:
Hypothyroidism is most commonly caused by an autoimmune reaction, where your body attacks healthy cells. Genetic and environmental factors both contribute to autoimmune thyroiditis. You can check your thyroid hormone levels with Everlywell's at-home thyroid test, which measures T3, T4, TSH, and thyroid peroxidase antibodies.
Another condition associated with weight gain is Cushing's syndrome (CS). In fact, weight gain is the most common symptom of CS. Individuals with CS may gain weight more on their face, neck, trunk, and abdomen than on their limbs. CS affects more individuals assigned female at birth (AFAB)
CS results from the excessive production of cortisol, also known as the stress hormone. There are many causes of CS, but the most common is the use of glucocorticoid medications, which are used to treat individuals with asthma and rheumatoid arthritis. Some other symptoms of CS include:
Treatment for CS is available, and many individuals with CS can be cured.
Polycystic ovary syndrome (PCOS) is caused by the excessive production of male hormones in the ovaries, resulting in irregular or no periods. PCOS is the leading cause of infertility in the United States, affecting 5% to 10% of women.
Women with PCOS often gain weight as a symptom. The cause of PCOS is unknown, but having obesity can increase your risk of developing PCOS. Other symptoms of PCOS are:
There is no cure for PCOS, but managing the condition through lifestyle interventions and medications is possible. For individuals with obesity and PCOS, losing weight can help alleviate some of the symptoms.
Depression is another condition associated with weight gain. Depression and weight gain have a bidirectional relationship, meaning depression can cause weight gain, and weight gain can cause depression. People who are depressed tend to crave fats and carbohydrates, resulting in weight gain. Additionally, medications commonly used to treat depression can also lead to weight gain.
Depression is caused by a variety of external and internal factors. Genetics, medications, stressful situations, and hormones play a role in depression. In general, women are more likely to experience depression than men. Aside from weight gain, other symptoms of depression include:
Medication, behavioral therapy, and lifestyle changes can help you manage depression.
Insomnia, or the inability to sleep, is another condition associated with weight gain. A bidirectional relationship exists between insomnia and weight gain, with insomnia leading to weight gain and weight gain leading to insomnia. Obesity increases the risk of sleep disorders, resulting in poor sleep quality.
Insomnia can lead to increased cravings for foods high in fat and carbohydrates. Additionally, sleep deprivation can impair one's ability to exercise. Sleep deprivation is generally defined as sleeping less than seven hours a night. The most common causes of insomnia are poor sleep habits, stress, and disruptions in sleep-wake cycles caused by shift work.
If you are experiencing insomnia, the following are some treatments and ways to manage the condition:
If you are experiencing weight gain, online weight loss visits are available via Everlywell. Virtual care visits are synchronous telehealth appointments with licensed nurse practitioners who can help you determine the cause of your weight gain. Your healthcare provider can suggest tests, lifestyle changes, and medications to help you get your health back on track.