Polyphagia: Physiology, Symptoms, Causes, Diagnosis, Effect of Insulin, Treatment, Complications and Prevention

One of the most important needs to make life possible is food.

The absence of food makes hell living and one cannot survive in the absence of it.

Many people starve because most developing countries cannot meet the demand for food. Enough food is required to stay healthy and is necessary for a fitter and better life.

Food meets all the required nutritional supply of the body and keeps infection and disease at bay.

Eating less under any circumstances, such as diets or the lack of food availability, can lead to health problems, and at the same time, overeating can cause various metabolic disorders .

Many people find it comfortable to eat a lot, while others make it an excessive habit considering that it is a normal thing to do.

Polyphagia or hyperphagia is excessive hunger or increased appetite, it is a medical condition in which a person feels a strong desire to eat a lot. In this condition, a person feels the urge to eat over and over again.

Normally a person can feel hungry when they have not eaten for a long time or if they have nothing to eat. People who engage in heavy physical activities may feel hungry due to the burned energy. A good appetite is also considered normal, as they can regulate your food intake.

What is the physiology of polyphagia?

There are many factors that cause increased food intake or polyphagia including gastrointestinal, environmental, and central nervous system factors. The hypothalamus, a center present in the central nervous system, is responsible for controlling eating behavior.

There is a “feeding center” which, upon stimulation, causes an animal to eat and severe and fatal anorexia can occur if the feeding center is destroyed.

On the other hand, there is another “satiety center” whose stimulation can cause a person to refuse to eat highly palatable foods, and the removal of this “satiety center” can lead to polyphagia and obesity.

The eating center is constantly active unless inhibited by the satiety center. Other factors that improve feeding behavior are lesions of the amygdala or paraventricular nuclei.

Gastric distention, gastric emptying rate, gastric hormone release, and nutrient absorption, such as fatty acids, glucose, and amino acids, are some gastrointestinal components that affect polyphagia and overeating.

Insulin, glucagon, and cholecystokinin are intestinal hormones that act on the gastrointestinal tract locally while they act on the central central nervous system. These hormones are secreted in response to a feeding signal from the central nervous system in the condition of a decline in a meal.

A feeling of satiety or satisfaction is created with the help of leptin (a polypeptide release from adipose tissue). An excess of hunger can be caused by glucose, amino acids or lipid metabolites, since they stimulate the neural centers in order to restore normal levels.

Adequate nutrient utilization or a high metabolic rate can help prompt eating behavior.

There are several central and peripheral inputs that are useful in controlling normal eating, so normal feeding control is a complex phenomenon that requires maintenance of energy reserves and body weight.


Polyphagia is itself a symptom of diabetes mellitus. It usually comes along with polydipsia and polyuria. Eating excessively is the only symptom of polyphagia. People with polyphagia are more prone to obesity and are more likely to gain weight.

If you feel that your appetite and appetite increases significantly and persistently, you should seek the help of a doctor. You should also contact them if there are changes in your appetite along with other symptoms.

What are the causes of polyphagia?

Certain factors cause excessive hunger or polyphagia. Eating is quite normal, but sometimes there are many underlying causes responsible for overeating. Some causes of polyphagia are very normal, while some are very different and severe, such as:

  • Diabetes.
  • Hypoglycemia (low blood sugar).
  • Hyperglycemia (high blood sugar).
  • Anxiety.
  • Stress .
  • Depression .
  • Bulimia.
  • Binge eating disorder
  • Hyperthyroidism (overactive thyroid).
  • Premenstrual symptom.
  • Medical prescription.
  • Psychiatric conditions.

Some causes are described here in detail:

Mellitus diabetes

The most important factor in overeating is type 1 diabetes or diabetes mellitus. In the early stage of diabetes mellitus, people may feel excessively hungry.

Foods that have high glycemic carbohydrates can increase the level of blood sugar and insulin in the body. Diseases such as diabetes mellitus cause one to digest carbohydrates quickly, thereby increasing appetite and thus making one feel a greater desire to eat more.

Hormonal imbalance

Hyperthyroidism is the hormonal imbalance that can cause excessive hunger or polyphagia. Your desire to eat may be increased by hyperadrenalism or an elevated level of adrenal hormones.

Pregnancy causes various changes in a woman’s body and many women are affected by problems such as polyphagia during pregnancy. During the menstrual cycle, some women experience polyphagia.

Anxiety and depression

Depression is also the leading cause of overeating. Few people divert their mind from depression by eating excessively to avoid facing the real condition. Therefore, anxiety, depression and stress are some of the main reasons for causing excessive hunger.

There are people who come to eat when they are completely stressed. However, few people stop eating under stressful conditions or cannot eat much under stress.

Klein-Levin syndrome

It is a malfunctioning disease in the hypothalamus . It is also one of the main causes of excessive hunger. Klein-Levin syndrome (SKL) is also known as sleeping beauty syndrome. Improves hunger excessively. This syndrome is also characterized by excessive sleepiness.

This is a disorder in which a patient sleeps most of the time and whenever he is awake he shows food cravings. Some people even just wake up to eat and then go back to sleep and then eat again. Eating excessively and sleeping excessively are two main characteristics of this syndrome.

Bulimia nervosa

It is another eating disorder. Mainly the younger generation is suffering from this disorder. Those who have more desire to eat can also suffer from this disease. A person begins to eat more in this disease, but to avoid excess weight or to avoid more weight, they try to purge.

To skip food, they begin to make desperate movements, such as vomiting, taking diet pills, exercising too much, sweating excessively with exercise, and may also use a laxative. In bulimia, people sometimes fast until they begin to starve.

This disorder is different from anorexia nervosa. However, both anorexia nervosa and bulimia nervosa are eating disorders.

They differ by the means of controlling their eating, since in anorexia nervosa their eating can be controlled, while in bulimia nervosa one has no control over their eating.

Prader-Willi syndrome

It is also an indication of polyphagia. This is a disorder of children in which children begin to eat after completing their first year of life due to continuous food cravings. They used to have the desire to eat as they grow older.


You may feel hungry again and very soon after eating if you eat a lot of unhealthy carbohydrates and fats, for example white bread or fast food. This is because these foods lack filling nutrients like fiber and protein. Try to eat more:

  • Fruits and vegetables.
  • Whole grains
  • Beans.
  • Lean meat and fish.

Other symptoms of a diet that is not nutritious enough include:

  • Weight gain or loss.
  • Fatigue.
  • Hair loss or thinning.
  • Swollen or bleeding gums.
  • Difficulty concentrating or remembering things.

Certain drugs

Some drugs can also cause excessive hunger, such as acitretin, a drug used to treat psoriasis. Many medications used to treat diabetes mellitus can cause polyphagia.

Of course, if you don’t stop eating too much, there are several risk factors that can occur. The most obvious are obesity. Serious and terrible illnesses could also be triggered.

How can the cause of polyphagia be diagnosed?

Polyphagia does not occur often without other symptoms. The underlying cause of polyphagia is diagnosed based on the accompanying symptoms.

If you feel that your appetite increases significantly and persistently, you should seek the help of a doctor. You should also contact them if there are changes in your appetite along with other symptoms.

Your current weight and physical exam can help your doctor understand the true cause of your excessive hunger. You can submit to a series of questions regarding your lifestyle, food intake, as well as eating habits. For instance:

  • Are you trying to diet?
  • Have you gained or lost a substantial amount of weight?
  • Did you change your eating habits before increasing your appetite?
  • What is your typical daily diet like?
  • What is your typical exercise routine like?
  • Have you been previously diagnosed with any chronic disease?
  • What prescription or non-prescription medications or supplements do you take?
  • Does your pattern of excessive hunger match your menstrual cycle?
  • Have you also noticed increased urination?
  • Have you felt thirstier than usual?
  • Have you been vomiting regularly, whether on purpose or not?
  • Are you feeling depressed, anxious or stressed?
  • Do you use alcohol or illegal drugs?
  • Do you have any other physical symptoms?
  • Have you recently been ill?

You must undergo many diagnostic tests, based on information about your symptoms and history. For example, blood tests and thyroid function tests to measure the level of thyroid hormones in your body.

Depending on your symptoms and medical history, they may order one or more diagnostic tests. For example, they may order blood tests and thyroid function tests to measure the level of thyroid hormones in your body.

A mental health professional may be recommended in case your doctor has not found any physical cause for your increased appetite. The mental health professional or a psychiatrist can perform a psychological evaluation.

Extreme thirst, fatigue, tingling or pain in the hands and feet, and blurred vision accompany polyphagia when it is caused by type 1 diabetes.

If it is accompanied by a rapid pulse, profuse sweating, muscle weakness, hand tremors, brittle hair, extreme thirst, nervousness, and the appearance of a goiter, then it is caused by hyperthyroidism.

When polyphagia occurs along with heart palpitations, dizziness, difficulty urinating, sweating, pale skin, numbness of the mouth and tongue, anxiety, and tremors, hypoglycemia is treated.

Psychotic episodes (hallucinations), headaches, insomnia, nervousness, and depression are symptoms of polyphagia caused by psychological disorders such as bulimia or chronic stress.

In women a missed period, frequent urination, nausea, and breast pain or enlargement point to polyphagia due to pregnancy.

Polyphagia that is accompanied by excessive sleep is caused by Klein-Levin syndrome. Patients sleep for prolonged periods waking up only to eat.

Symptoms come in waves and last for days or weeks before disappearing for months. When awake, the person also suffers from disorientation, lethargy, lack of emotional response, and even hallucinations.

Polyphagia in children with almond-shaped eyes, underdeveloped sex organs, and speech and motor disabilities is caused by Prader-Willi Syndrome.

What is the effect of insulin on polyphagia?

An adipose tissue is affected by insulin. The release of insulin can improve the feeling of hunger. Insulin release can be easily stimulated by the naked eye and the smell of food. This results in increased appetite, improved taste, and inevitably more food.

The more physiological response leads to greater weight gain. Therefore, studies showed that increased insulin release into the bloodstream can cause excessive hunger.

Interestingly, the release of insulin into the bloodstream can cause more food by enhancing the sweet taste or enhancing the sensitivity of the sweet taste buds in the mouth.

According to studies, overeating is a combination of many factors, such as environmental, biological and behavioral changes.

Scientists measured the insulin level in people who eat a different type of food and found that people like to eat different foods in case of increased insulin release.

Can diabetes mellitus cause polyphagia?

Polyphagia can be defined as poly means “a lot” and phagia means “to eat.” So, polyphagia can easily be understood as “eating a lot.” A person suffering from diabetes mellitus tends to eat more than normal.

A diabetic person feels the need to eat more and their meals become more frequent than usual. A common cause of polyphagia is hypoglycemia.

Diabetes is a disease in which the body cannot process sugar properly, as a result of which the body develops insulin resistance or may have little insulin. The cells of the body remained starved due to the inability of the body to convert food into energy.

Diabetes is the most common cause of polyphagia, however, this is not just one cause. As previously stated that polyphagia is one of the symptoms of diabetes, other symptoms include polydipsia ( excessive thirst ) and polyuria (excess urination).

One should be careful in the case of diabetes and seek help from their dietitian or doctor. As the polyphagia that arose from diabetes can cause weight gain and overeating, this can cause additional complications in diabetes. Your doctor will balance your food to ensure adequate nutrition in your diet.

A diabetic patient should eat small meals throughout the day, which helps prevent the symptoms of polyphagia and other episodes.

Another beneficial factor in the treatment of polyphagia is insulin, which must be taken under the supervision of a physician. Insulin must be taken under the proper guidance of a physician because every case of diabetes is different.

Why does polyphagia occur in hypoglycemia and hyperglycemia?

Hunger and hypoglycemia

Hunger is a symptom of hypoglycemia and hyperglycemia. Hypoglycemia is also known as low glucose levels, while hyperglycemia is known as high glucose levels in the blood stream.

Some stories are known in which a patient is unable to control himself from eating even unconsciously. The blood glucose level of said patient is found to be 80 upon verification.

They have a nightly minimum, and end up in a confusing binge, judging by the empty milk jug, or the cookie wrappers next to it.

Hunger can be a driving force. In other words, it has been said that when our cells lack energy, we will do anything to get fuel.

Hunger and hyperglycemia

Hyperglycemia is also known as high glucose levels. Not only hypoglycemia but also hyperglycemia can cause excessive hunger or polyphagia.

This phenomenon can be easily understood as hunger is related to a lack of insulin also when there is less energy available to the cells of your body.

In hyperglycemia, when you eat, the glucose begins to float in the bloodstream instead of being in the required location. Therefore, cells continue to starve without obtaining the required energy. In hyperglycemia, a person can eat continuously without being satisfied.

Why do people with diabetes get more cravings?

You get energy for even the smallest activity only when you eat. Even to blink, you need energy and that energy comes from the food you eat. Sugars, proteins, and fats are the building blocks of the foods you eat.

And these building blocks are the basic sources of energy for your body. The cells of the body satisfy their energy levels with the help of sugar that is present in food. Insulin is a hormone that is required to break down the sugar you eat that is present in food.

Insulin breaks down sugar for energy and makes all cells in the body available. In type 1 diabetes, your body doesn’t make enough insulin, alternatively, in type 2 diabetes, your body makes enough insulin but it doesn’t work the way it’s supposed to.

In such a case, the insulin begins to float in the bloodstream instead of being in the exact place. When insulin doesn’t work properly, the body can’t convert glucose into energy, so the body’s cells begin to starve. At the same time, you feel like eating.

Similarly, in the case of hyperglycemia, you eat and eat more, you don’t feel full, which can increase your chances of obesity.

So it all depends on the function of insulin, if our body produces enough insulin or if it works well converting glucose into energy properly, you will feel satisfied and you will not feel like you eat again and again.

A diabetic patent consumes more than normal when they have little energy. The brain sends signals to the body and informs that “it is time to eat.” Since the sugar in food is not being converted into energy, you continue to eat to give the tissues the required amount of sugar and energy that you want.

Unfortunately, that is why people with diabetes eat a lot. Keep in mind that, in most cases, there are ways to avoid overeating.

By eating properly you can help reduce cravings, be sure to consult your doctor or seek medical advice from a licensed professional on a proper diet that is right for you.

What is drug-induced polyphagia?

According to studies, overeating is a combination of many factors, such as environmental, biological and behavioral changes. A craving for carbohydrates and an increased appetite can be caused by some medications, such as tricyclic antidepressants, for example imipramine, amitriptyline, and doxepin.

Other drugs that increase appetite include first-generation antihistamines , most antipsychotics, and systemic corticosteroids. Some other medications that cause polyphagia and excessive food intake include:

  • Glucocorticoids.
  • Anticonvulsants
  • Antihistamines.
  • Progestinas.
  • Benzodiazepines.
  • Amitraz.
  • Ciproheptadina.

What is secondary polyphagia?

When overeating is caused by non-neural factors and a higher metabolic rate or less nutrient supply, it is known as secondary polyphagia. Physiological (pregnancy) and pathological (hyperthyroidism) can be the origin of the increased metabolic rate.

The decrease in nutrient supplies occurs mainly in the case of diabetes mellitus. Lack of insulin makes the body unable to recognize glucose and reacts to perceived hypoglycemia.

Certain diseases such as hyperadrenocorticism and liver disease can cause polyphagia by unknown mechanisms. Certain medications can also contribute to secondary polyphagia.

Which is the treatment?

Polyphagia is not a disease, it is a symptom of an underlying disease, such as diabetes, hormonal imbalance, and anxiety, etc., therefore your treatment should focus on treating the underlying disease that polyphagia will eventually treat.

It is important to note that it is not a contagious disease and that it can be treated and controlled. Because polyphagia is more of a symptom of a certain disorder or disease, the applicable treatment varies depending on the medical condition. Therefore, treatment must be applied directly to its cause.

Diabetes-related polyphagia is treated through a combination of blood sugar monitoring, diet adjustments, and proper insulin administration.

In genetic and hormonal disorders, the medicine is prescribed to alleviate the symptoms of the root disease. Hyperthyroidism is treated with prescription medication. In some extreme cases, radioactive therapy or surgery may be done to remove part of the thyroid.

For cases such as pregnancy or metabolism, it is recommended to eat and wait for it to pass. If polyphagia is caused by a new medication, one should address this with their physician for alternative medication.

Genetic disorders that cause polyphagia; for example, Kevin-Levin syndrome and Prader-Willi syndrome are treated from an early age to control symptoms.

If doctors cannot find the underlying cause of the polyphagia, the patient is referred to a mental health expert who finds out if the condition is psychological.

Psychiatrists or psychotherapists care for and prescribe medications to patients for polyphagia caused by underlying psychological problems. Certain therapy is applied to overcome overeating and suppress appetite.

Patients who have diabetes must take the necessary medications to regulate their blood sugar level. In patients with hyperthyroidism, prescription medications should be taken. Surgery and radioactive therapy may be necessary in some patients depending on the severity of the disease.

You should always see your doctor immediately for any disorder you may feel.


Obesity is the main complication arising from polyphagia, especially in children. Diseases such as heart failure or high blood pressure, for which obesity is a predisposing factor, can also be caused in the long term by polyphagia.

The depression , anxiety, bulimia nervosa and other psychological disorders can arise from polifagia.


Most of the underlying causes that cause polyphagia cannot be prevented, however, positive lifestyle choices can protect you from risk factors, thus reducing your predisposition to conditions that cause polyphagia, such as, diabetes.