Hunger

Symptoms of hunger can be more than a reminder for our next meal. Hunger is most commonly a response to food deprivation, fasting, or restricted eating, but there are other causes of hunger. Lifestyle factors, medical conditions, and medications can cause hunger. This article discusses the symptoms, causes, and treatment of hunger.

Symptoms of Hunger

Hunger is a physiological sensation of needing food that encourages us to seek our next meal. When the nutrients in the blood are low, the hormone ghrelin, sometimes called the "hunger hormone," is released from the gut—these chemical messengers travel to the brain and trigger hunger.

Hunger can be an uncomfortable physical sensation. Symptoms of hunger include:

• Abdominal pain or cramping or contractions in the stomach
• Cravings for high-energy foods, like sweets and carbohydrates
• Empty or growling stomach
• Grumpiness
  
• Headache
• Light-headedness
  
• Low energy
• Shakiness or weakness
  
• Thinking about food constantly

Causes of Hunger

Beyond the need to eat, other conditions can cause hunger independent of food intake, including lifestyle, blood sugar levels, medical conditions, and pregnancy.

Lifestyle

• Dieting and food restriction: Studies have shown that weight loss from dieting is linked to increased hunger and appetite.
• Environment and social cues: Your perception of hunger can be influenced by your environment and social cues, such as the proximity to mealtime, the time since your last meal, and your perceived attractiveness or anticipated sensory quality of the food you will eat.
• Exercise: Changes in physical activity levels may lead to hunger if your body needs more nutrients to meet the demand.
  
• Sleep: Sleep plays a role in regulating blood sugar levels. When you are sleep deprived (lacking sleep), the hypothalamus, a region of the brain responsible for regulating appetite, is affected.
• Smoking cessation: Cigarettes act as an appetite suppressant, making the body consume more calories. Quitting this habit can, in turn, increase hunger and appetite.
• Stress: Prolonged, uncontrolled stress affects eating patterns. Over time, chronic stress can change how your body breaks down glucose and responds to insulin. It also affects appetite, making us crave and eat energy-dense foods.
• Trauma: Chronic stress and trauma is associated with an increase in the hormone acyl-ghrelin for its role in stimulating appetite.
  

Blood Sugar

• Diabetes: Individuals with type 1 or 2 diabetes who take insulin may be at risk for low blood sugar. Missing a meal, taking too much insulin, or taking other diabetes medication can cause hypoglycemia (low blood sugar).
• Insulinoma: Insulinoma is a rare pancreatic tumor that causes insulin overproduction, causing low blood sugar and triggering hunger.
• Low blood sugar: Hypoglycemia causes hunger.

Medical Conditions

• Congenital leptin deficiency: Leptin, or the "fullness hormone," signals to the brain that we are full. Therefore, deficiency in this hormone causes a constant feeling of hunger.
• Hyperthyroidism: The thyroid is a gland responsible for making hormones that affect how the body uses energy. An overactive thyroid (hyperthyroidism) causes an increase in this hormone, resulting in hunger. Graves' disease is an autoimmune disorder that can cause hyperthyroidism.
• Leptin receptor deficiency: Like congenital leptin deficiency, in leptin receptor deficiency, a person produces leptin, but they are not responsive to it, resulting in a constant feeling of hunger.
• Prader-Willi Syndrome: Prader-Willi Syndrome is a rare genetic disorder that causes the part of the brain controlling hunger and satiety not to work correctly, leading to constant feelings of hunger.

Pregnancy

During pregnancy, pregnant people may experience changes in hunger signs. The calories required of the pregnant parent to support fetal growth and development increase. In most cases, pregnant people need an additional 340 and 450 calories daily during the second and third trimesters.

What Medications Can Cause Hunger?

Several types of medications are associated with hunger and weight gain. It's important to discuss symptoms, including changes in appetite, with your healthcare provider. Common types of medications that cause hunger include:

• Antidepressants, such as Zoloft (sertraline) and Remeron (mirtazapine), are used to treat depression. There are five classes of antidepressants, and newer drugs may have a lesser impact on increasing hunger and weight gain.
• Antihyperglycemics, such as Diabeta (glyburide) or Amaryl (sulfonylureas) and Actos (pioglitazone), treat diabetes by lowering blood sugar levels and increasing insulin sensitivity. Newer classes of medication may not have the same effect on hunger.
• Antipsychotics and mood stabilizers, such as Zyprexa (olanzapine) Clozaril (clozapine), treat mental health disorders, including schizophrenia and bipolar disorder. Antipsychotics affect signaling molecules that control appetite. 
• Corticosteroids, such as prednisone and hydrocortisone, treat conditions like asthma, inflammatory disorders, skin disorders, and autoimmune diseases. Long-term use is associated with changes in appetite and weight.
  

How to Treat Hunger

If hunger is the result of food restriction and not meeting the body’s energy demands, listening to those cues and eating can treat hunger.

Eating triggers nerves in the upper digestive tract that tell the brain to turn off the hunger signal. This signaling takes time, so eating slowly allows time for the brain and body to feel full.

Eating more will not address the issue if hunger is caused by an underlying lifestyle or medical problem. Working with a healthcare provider to identify and understand the cause of hunger will help determine the best treatment. Speak to a healthcare provider before drastically changing your lifestyle or medications.

Are There Tests to Diagnose the Cause of Hunger?

Diagnostic tests will vary depending on your medical history. A healthcare provider may take a blood sample to check your blood sugar or thyroid hormone levels. If the underlying cause is related to lifestyle, they may ask questions to determine if dieting, sleep, stress, or smoking cessation are causing a change in hunger. 

When to See a Healthcare Provider

Unexplained changes in hunger and appetite may require medical attention to find the underlying cause. A healthcare provider can help rule out medical conditions like diabetes or hyperthyroidism and determine if there should be changes in medications.

Summary

Hunger is a complex symptom influenced by many factors. Lifestyle, blood sugar levels, medical conditions, pregnancy, and medications can all cause changes in hunger. There are various ways to treat hunger. A healthcare provider can help identify the underlying cause and determine the best treatment.

A Word From Verywell

Hunger is an important cue that helps you meet your body’s needs. In cases like pregnancy, dieting, and exercise, hunger is a way to ensure you get enough nutrients. Other times, hunger can bring attention to a lifestyle behavior that needs changing or a health condition you may not be able to control. Regardless of the cause, never ignore changes in hunger or appetite.