Also called: Disorder of Hyperalimentation, Hyperphagia, Excessive Hunger, Increased Appetite
Polyphagia is the medical term for excessive hunger or eating. It is a common symptom of diabetes but may also indicate other conditions.
Excessive hunger is not always easily explained because all individuals have unique caloric needs based on a variety of factors, including age, body size and activity level. People who are very hungry after an extended period without food, and those who have always had a large appetite, do not have polyphagia.
Polyphagia is often an acute symptom caused by hypoglycemia (low blood glucose), a condition that affects many people with diabetes. Other causes of polyphagia may include anxiety, eating disorders, hyperthyroidism and pregnancy.
Unexplained weight loss may accompany polyphagia in people with type 1 diabetes. However, many people with type 2 diabetes who have polyphagia gain weight after overeating. Individuals who feel compelled to overeat are advised to contact their physician.
Diagnosis of polyphagia begins with a medical history and physical examination. Treatment of polyphagia is directed at its cause. For example, an individual with diabetes may be prescribed exercise, diet and possibly insulin or other medication.
Polyphagia, also known as hyperphagia, is the medical term for excessive hunger or eating. Hunger is a normal desire or need for food. Individuals with polyphagia consume excessive amounts of food before experiencing feelings of fullness (satiety).
Increased hunger is not typically considered excessive if it follows a recent lack of eating. Individuals who have always had a hearty appetite are not considered polyphagic either.
Excessive hunger is not easily explained because every individual has unique caloric needs based on:
- Basal metabolic rate (BMR, the rate at which a person expends energy during rest)
- Body size and composition
- Physical condition
- Level of activity
The National Institute of Diabetes and Digestive and Kidney Disease (NIDDK) offers the following daily caloric recommendations:
|Small, active||1,200 to 1,600|
|Small/medium, trying to|
|1,200 to 1,600|
|Medium, inactive||1,200 to 1,600|
|Large, trying to lose weight||1,600 to 2,000|
|Large, active||2,000 to 2,400|
|Small, at healthy weight||1,600 to 2,000|
|Medium, inactive||1,600 to 2,000|
to lose weight
|1,600 to 2,000|
|Medium/large, active||2,000 to 2,400|
|Large, at healthy weight||2,000 to 2,400|
A physician may make other recommendations based on a patient’s individual needs, concerns and conditions.
Depending on its cause, polyphagia can be intermittent or persistent. Individuals who experience polyphagia may or may not gain weight.
Polyphagia and diabetes
Polyphagia is a common sign of diabetes. This is because diabetes is characterized by the body’s inability to produce (in type 1 diabetes) or properly use (in type 2 diabetes) insulin. Insulin is a hormone produced by the pancreas to regulate glucose (blood sugar).
When insulin is lacking, glucose builds up in the bloodstream instead of entering the cells. The body is unable to use this glucose for energy. In other words, lack of insulin causes the cells to enter a state of starvation even though there is an excess of sugar in the blood. This condition, which can affect all types of diabetes, is called hyperglycemia. Other symptoms of hyperglycemia due to diabetes include polydipsia (excessive thirst) and polyuria (excessive urination).
When people with diabetes experience hyperglycemia, they may feel as though they are starving, despite overeating. This voracious hunger does not diminish until blood glucose finally enters the cells. In type 1 diabetes, the body, which normally burns glucose for fuel, may begin to burn fat instead. This is why many polyphagic individuals with type 1 diabetes report unexplained weight loss despite consuming an inordinate number of calories.
Type 2 diabetes is associated with a condition called insulin resistance. The body produces enough insulin to meet its needs but is unable to detect or use the hormone properly. The body is therefore unable to transfer glucose from the bloodstream to the cells, and hyperglycemia ensues. Many people with type 2 diabetes and polyphagia gain weight because insulin resistance and overeating result in excess production of insulin. This hyperinsulinemia, in turn, results in the storage of excess food, which increases body fat.
Individuals with other forms of diabetes, including gestational diabetes (diabetes that occurs during pregnancy), latent autoimmune diabetes of adulthood (LADA), maturity-onset diabetes of the young (MODY) and secondary diabetes, may also experience polyphagia. Sometimes people with prediabetes may have polyphagia.
Other diabetic conditions that can trigger polyphagia include low glucose (hypoglycemia), which causes the autonomic nervous system to produce symptoms such as hunger and shakiness, and diabetic ketoacidosis, in which the body burns fats rather than glucose for energy.
Other potential causes of polyphagia
In addition to diabetes, hyperglycemia, hypoglycemia and diabetic ketoacidosis, common causes of polyphagia include:
- Increased exercise.
- Growth spurt.
- Anxiety, depression, bipolar disorder or eating disorders such as bulimia.
- Premenstrual syndrome (PMS).
- Certain drugs, including corticosteroids (a class of anti-inflammatory immunosuppressives), antidepressants, some antidiabetic agents (e.g., sulfonylureas), antibiotics, anticonvulsants (sometimes used to treat diabetic neuropathy), antihistamines, cholesterol drugs, and cannabinoids such as marijuana.
- Hyperthyroidism, a condition characterized by a high level of thyroid hormone, caused by disorders including Graves’ disease.
- Hyperadrenalism (Cushing’s syndrome), a condition characterized by a high level of adrenal hormones.
- Damage to the hypothalamus (the part of the brain that controls hunger), which may be due to conditions such as head injury, tumor or encephalitis. Certain rare genetic diseases associated with polyphagia and obesity are thought to be due to inborn disorders of the hypothalamus, such as Prader-Willi syndrome.
- Intestinal parasites such as tapeworms.
- Kluver-Bucy syndrome, a rare disorder involving damage to the temporal lobes of the brain due to causes such as trauma, dementia or hypoglycemia.
Diagnosis and treatment of polyphagia
People with diabetes and other individuals who experience an overwhelming, pathological desire to consume an excessive amount of food should notify their physician. Diagnosis of polyphagia begins with a medical history and physical examination. The physician will ask questions such as:
- Has there been a recent change in eating habits?
- What types of foods are consumed in a typical day?
- How much food does the patient eat in a typical day?
- Is the patient taking any new medications?
- Does the patient use any recreational drugs?
- Does hunger occur during sleep?
- Does hunger occur just prior to menstruation?
- Does the patient drink and urinate frequently?
- Has the patient experienced an unintentional weight loss or gain?
- Could the patient be pregnant?
Psychological evaluation will also be performed in certain cases. Additionally, the physician may perform diagnostic tests, such as:
- Blood tests, including glucose tests, commonly used to detect diabetes, and thyroid functiontests, used to detect hyperthyroidism.
- Toxicology screen. A test used to detect recreational drug use.
- Cranial CAT scan (computed axial tomography). A type of x-ray of the brain, which can identify damage to the hypothalamus, the part of the brain that controls hunger.
Treatment of polyphagia is directed at its cause. For instance, a diabetic individual may be prescribed insulin (a hormone that regulates glucose) or antidiabetic agents to lower glucose (blood sugar). A patient who has hyperthyroidism may require medication, surgery or radiation therapy, and individuals with anxiety or depression may benefit from medication and mental health counseling.
Individuals who experience increased hunger because of a growth spurt or pregnancy typically do not require further treatment. Those who stop abusing drugs will generally resume their normal appetite.
Questions for your doctor about polyphagia
Preparing questions in advance can help patients have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions about polyphagia:
- How can I tell whether my hunger is normal or can be considered polyphagia?
- What tests for polyphagia might I need to undergo?
- What do my test results show? Do I have polyphagia?
- Does having polyphagia mean I have prediabetes or diabetes?
- What other disorders could my polyphagia be a symptom of?
- What could it mean if my hunger is accompanied by weight loss or by weight gain?
- What if my excess hunger occurs alongside extreme thirst (polydipsia) and excess urination (polyuria)?
- What is causing my polyphagia?
- What are my treatment options for polyphagia and its underlying cause?
- Do I need to be monitored with additional tests?