What is Considered Rapid Weight Gain? Rapid Weight Gain Causes

Understand your rapid weight gain symptoms, 9 causes & treatment options for your rapid weight gain.

  1. Rapid Weight Gain Symptoms
  2. Rapid Weight Gain Causes
  3. 9 Possible Rapid Weight Gain Conditions
  4. Rapid Weight Gain Treatments & Prevention
  5. Real-Life Stories
  6. Rapid Weight Gain FAQ
  7. Questions Your Doctor May Ask
  8. Statistics
  9. Related Articles
  10. References

Rapid Weight Gain Symptoms

Rapid or unintentional weight gain happens when your weight increases without increased consumption of food or decreased activity.

Symptoms associated with rapid weight gain can be different between each person. But most people will immediately notice that clothing items such as shoes and pants no longer fit.

Common accompanying symptoms of rapid weight gain

If you're experiencing rapid weight gain, it's also likely to experience:

Rapid unintentional weight gain is not a normal process and should always be followed up with your physician. These symptoms usually signal an underlying medical issue.

Rapid Weight Gain Causes

Causes of rapid, unintentional weight gain can be separated into three broad categories. Endocrine disorders, systemic conditions that cause fluid retention and medications [1].

Endocrine-related causes

The endocrine system is a series of glands that produce hormones important in the regulation of metabolism, growth and development. Both normal functioning and dysfunction in this system can cause rapid weight gain for multiple different reasons.

  • Reproductive: The endocrine system is responsible for the regulation of the reproductive functions in the body such as pregnancy and the menstrual cycle. Rapid weight gain within certain ranges during pregnancy is normal as the body puts on extra weight in form of the baby, placenta, enlarging uterus and increased blood supply. Rapid weight gain is also normal during menopause. The decrease in estrogen levels associated with menopause often results in extra fat or weight gain in the abdominal region and hips [2].
  • Regulatory: The endocrine system is also responsible for regulation of the thyroid gland. This gland is important for making hormones that allow the body to burn calories. As a result, dysfunction in the thyroid gland, especially lack of hormones (hypothyroidism) can result in rapid, unintentional weight gain [1]. The pituitary gland is part of the endocrine system that releases multiple hormones, including one for growth. When too much growth hormone is produced, a condition called acromegaly occurs. Not only do people with acromegaly gain weight rapidly, the bones of the face, hands and feet also increase in size [3].
  • Metabolic: The endocrine system also regulates insulin. In diabetes, there is dysfunction in insulin control that results in high levels of glucose in the blood. Rapid weight gain is often a first sign of diabetes in addition to symptoms such as increased urinary frequency and thirst.

Fluid retention

Swelling is the result of fluid buildup (edema) that gets trapped in your body's tissues. Buildup can occur when fluid cannot properly flow and/or drain. Fluid retention throughout the body (anasarca) can result in rapid weight gain that is very noticeable in the extremities, especially the legs.

  • Cardiac: Problems with the heart and its ability to pump effectively (also known as congestive heart failure) will cause blood to back up in the lower body [4]. This causes excessive pressure in the blood vessels that causes damage and leakage of fluid into the body's tissue. Furthermore, if the veins of the circulatory system are weakened or damaged, swelling will occur in a similar manner.

  • Kidney: The kidney is a potent regulator of bodily fluid because it is responsible for filtering and clearing the blood. Without the kidney, filtrate such as proteins, electrolytes and toxins can remain in the blood and act as forces that draw fluid out. Fluid retention is a very common and prominent side effect of kidney disease.

  • Liver: Severe liver disease can also result in fluid retention because of a reduction in protein production by the liver. Low levels of blood protein permit more leakage into the tissues.


The endocrine system also regulates a hormone in the body called cortisol. Cortisol is released by the adrenal glands and is very important for a number of the body's functions, including conversion of nutrients into energy. Sometimes patients have to take medications called corticosteroids for conditions that cause inflammation. Corticosteroids can result in a condition called Cushing's Syndrome [5]. Too much cortisol results in symptoms such as rapid weight gain, a rounded face, and pink or purple stretch marks on your skin.

9 Possible Rapid Weight Gain Conditions

The list below shows results from the use of our quiz by Buoy users who experienced rapid weight gain. This list does not constitute medical advice and may not accurately represent what you have.

Rheumatoid arthritis

Arthritis is a general term for multiple conditions that cause painful inflammation and stiffness throughout the body. Rheumatoid arthritis (RA) is a chronic condition that is autoimmune in nature, meaning that the body's immune system which normally protects the body by att...

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Sleep deprived

Sleep deprivation is also called sleep debt. It is the state of not getting adequate sleep, either in the short term or the long term.

Sleep apnea is a common cause, as is the routine of modern life with too many hours of work and activities.

Symptoms include clumsiness, irritability, difficulty concentrating, memory lapses, slow healing, daytime sleepiness, and sometimes depression. Often there is weight gain, partly due to metabolic disturbance and partly due to eating more in an effort to maintain energy and continue working.

Sleep deprivation interferes with quality of life. There is risk of job loss due to inability to concentrate, as well as risk of accidents from becoming sleepy while driving or operating machinery. Weight gain and Type 2 diabetes are both more common in those who are chronically sleep deprived.

Diagnosis is made through patient history and sometimes through a sleep study in a lab.

Treatment involves addressing any underlying medication issues or other causes, as well as establishment of "sleep hygiene" habits and routines that contribute to better sleep.

Rarity: Common

Top Symptoms: fatigue, daytime sleepiness, sleep duration less than 7 hours, difficulty concentrating

Symptoms that always occur with sleep deprived: sleep duration less than 7 hours, daytime sleepiness

Symptoms that never occur with sleep deprived: nausea or vomiting, being severely ill, fever, unintentional weight loss

Urgency: Wait and watch

Chronic obstructive pulmonary disease (copd)

Chronic obstructive pulmonary disease (COPD) is a progressive inflammation of the lungs that makes breathing difficult. It is caused by long-term exposure to irritating gases and/or dust particles, most often cigarette smoke.

Symptoms may take years to develop. They include a chronic cough with mucus (sputum), wheezing, chest tightness, fatigue, constant colds, swollen ankles, and cyanosis (blue tinge to the lips and/or fingernails.) Depression is often a factor due to reduced quality of life.

Treatment is important because there is a greater risk of heart disease and lung cancer in COPD patients. Though the condition cannot be cured, it can be managed to reduce risks and allow good quality of life.

COPD is commonly misdiagnosed and so careful testing is done. Diagnosis is made through patient history; physical examination; lung function tests; blood tests; and chest x-ray or CT scan.

Treatment involves quitting smoking and avoiding exposure to other lung irritants; use of inhalers to ease symptoms; steroids; lung therapies; and getting influenza and pneumonia vaccines as recommended.

Rarity: Common

Top Symptoms: fatigue, cough and dyspnea related to smoking, cough, shortness of breath, trouble sleeping

Symptoms that always occur with chronic obstructive pulmonary disease (copd): cough and dyspnea related to smoking

Symptoms that never occur with chronic obstructive pulmonary disease (copd): rectal bleeding

Urgency: Primary care doctor

Acute kidney injury

Acute kidney injury, also called acute renal failure or acute kidney failure, does not necessarily refer to a physical injury. It means that the kidneys have been severely damaged and are suddenly no longer able to filter wastes from the blood.

Anything that interferes with blood flow to the kidneys, or to the urine draining from them, will injure the kidneys. This includes: blood loss; clots; heart disease; high blood pressure; diabetes; infection; dehydration; lupus; toxins; and any number of medications.

An older person who is hospitalized, and/or critically ill, is most susceptible.

Symptoms include decreased urine output; swollen ankles; shortness of breath; nausea; chest pain; and sometimes seizures or coma.

Acute kidney injury is a medical emergency. Left untreated, it can result in permanent kidney damage or death. Take the patient to the emergency room or call 9-1-1.

Diagnosis is made through urine tests, blood tests, ultrasound or CT scan of the kidneys, and sometimes kidney biopsy.

Treatment involves hospitalization to treat the underlying cause of the kidney injury, and may include dialysis.

Rarity: Rare

Top Symptoms: abdominal pain (stomach ache), nausea or vomiting, urinary changes, shortness of breath, fatigue

Symptoms that always occur with acute kidney injury: urinary changes

Symptoms that never occur with acute kidney injury: vaginal bleeding

Urgency: Hospital emergency room

Rapid Weight Gain Symptom Checker

Take a quiz to find out what might be causing your rapid weight gain

Gestational diabetes

When diabetes develops during pregnancy, it is known as gestational diabetes. Excessive glucose in the blood (hyperglycemia) in a pregnant woman who has gestational diabetes increases the risk of pregnancy complications and health risks to her and her baby. Having gestational ...

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Acute or worsening heart failure

Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Heart failure does not mean that the heart has stopped or is about to stop working, but rather that the heart is not able to pump blood the way it should. Usually this happens when the heart has been damaged by another medical condition.

Rarity: Rare

Top Symptoms: fatigue, shortness of breath, chest pain, nausea, shortness of breath on exertion

Urgency: Emergency medical service

Congestive heart failure

Heart failure is a condition in which the heart is no longer able to effectively pump blood to the rest of the body. Heart failure can affect the right side, left side, or both sides of the heart. It can be subcategorized as "heart failure with preserved ejection f...

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Nephrotic syndrome

Nephrotic syndrome is a disorder of the kidneys that results in too much protein excreted into your urine. It is usually associated with damaged kidneys specifically damage to the kidneys' filters, called glomeruli.

Kidney damage and nephrotic syndrome primarily include albuminur...

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Cirrhosis is scarring of the liver. Scar tissue forms because of injury or long-term disease. In the United States, alcoholism and Hepatitis C are the most common causes. Scar tissue cannot do what healthy liver tissue does - make protein, help fight infections, clean the blood, help digest food and store energy.

Rarity: Common

Top Symptoms:

Urgency: Primary care doctor

Rapid Weight Gain Treatments and Relief

When to see a doctor for rapid weight gain

Treatment for rapid weight gain depends on the cause and finding the underlying issue. You should consult your doctor, who may recommend the following.

  • Additional medications: Endocrine causes of rapid weight gain that result in hormonal imbalance may be treated by medications that help to normalize the levels. These medications are often used long-term and are specific for the hormones affected.
  • Evaluation and testing: Cardiac, renal (kidney) or hepatic (liver) causes of fluid retention require evaluation and often multiple tests before treatment can be tailored to the patient's needs.
  • Medication changes: If medication is the cause of the problem, your doctor will recommend alternative rapid weight gain treatments.

When rapid gain is an emergency

Seek medical attention immediately if you experience symptoms such as:

Such symptoms may signal life-threatening complications of conditions such as diabetes or heart failure that require prompt medical attention.

Real-life Stories

Once your story is reviewed and approved by our editors, it will live on Buoy as a helpful resource for anyone who may be dealing with something similar. If you want to learn more, try Buoy Assistant.

FAQs About Rapid Weight Gain

Here are some frequently asked questions about rapid weight gain.

Why am I gaining weight but eating the same?

Weight gain can be caused by changes in the functioning of many of the glands in the body as well as changes in caloric consumption that is rarely considered by individuals. Hypothyroidism as well as excessive amounts of cortisol or overtreated inadequate levels of cortisol can contribute to unintended weight gain. Additionally, drinks like beer or soft drinks are often not considered food but are very high in calories.

Can depression cause rapid weight gain?

Depression can cause rapid weight gain or rapid weight loss. Depression can slow down metabolism, eliminate motivation to work out, motivation to eat healthy foods, or cause people to self-medicate an absence of positive emotion with food. It is common for severe fluctuations in weight to occur in the setting of the different stages of depression.

What is considered rapid weight gain?

Rapid weight gain is considered problematic if it greater than five percent of an individual's body mass in six months or less with no discernible reason. More often than not, it can be due to changes in diet, water consumption, and retention of water.

Do certain medications lead to rapid weight gain?

Yes, drugs that treat diabetes, bipolar disorder and schizophrenia, depression, or epilepsy can all cause rapid weight gain [6]. Insulin drugs may require a concurrent change in diet to avoid weight gain, and bipolar, depression, and schizophrenia drugs will require monitoring of weight gain and even lipid panels depending on the drug to monitor their effects.

Questions Your Doctor May Ask About Rapid Weight Gain

To diagnose this condition, your doctor would likely ask the following questions:

  • Have you been feeling more tired than usual, lethargic or fatigued despite sleeping a normal amount?
  • Are you having difficulty concentrating or thinking through daily activities?
  • Any fever today or during the last week?
  • Do you currently smoke?

If you've answered yes to one or more of these questions

Rapid Weight Gain Symptom Checker

Take a quiz to find out what might be causing your rapid weight gain

Rapid Weight Gain Symptom Checker Statistics

People who have experienced rapid weight gain have also experienced:

  • 8% Fatigue
  • 5% Stomach Bloating
  • 3% Severe Fatigue

People who have experienced rapid weight gain were most often matched with:

  • 50% Rheumatoid Arthritis
  • 50% Chronic Obstructive Pulmonary Disease (Copd)

Source: Aggregated and anonymized results from Buoy Assistant (a.k.a. the quiz).

Rapid Weight Gain Symptom Checker

Take a quiz to find out what might be causing your rapid weight gain


  1. Healthy Weight: Nine Medical Reasons for Putting on Weight. NHS. Updated June 1, 2017. NHS Link.
  2. Davis SR, Castelo-Branco C, Chedraui P, et al. Understanding Weight Gain at Menopause. Climacteric. 2012;15(5):419-429. Taylor & Francis Online Link.
  3. Acromegaly. National Institute of Diabetes and Digestive and Kidney Diseases. Published April 2012. NIDDK Link.
  4. Managing Heart Failure Symptoms. American Heart Association. Updated May 31, 2017. AHA Link.
  5. Cushing's Syndrome. Stanford Health Care. Stanford Health Care Link.
  6. Shrivastava A, Johnston ME. Weight-Gain in Psychiatric Treatment: Risks, Implications, and Strategies for Prevention and Management. Mens Sana Monographs. 2010;8(1):53-68. NCBI Link.

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