Hunger is the feeling that our bodies get when we’re running low on food and need to eat.

Under normal circumstances, hunger and appetite are regulated by a variety of mechanisms. In some cases, however, underlying causes can lead to abnormal appetite and hunger levels.

In this article, we’ll explore:

  • what causes hunger
  • why you may not feel hungry
  • ways to increase your appetite

Hunger is the feeling or sensation of wanting to eat. When the body is running low on fuel, feelings of hunger and an appetite for food increase.

Hunger levels are regulated by:

The hypothalamus of the brain plays an important role in hunger and appetite. In this area of the brain, a population of neurons regulates function dealing with appetite and the feeling of hunger.

These neurons produce or work in conjunction with certain hormones, such as neuropeptide Y (NPY), agouti-related peptide (AgRP), and ghrelin, to stimulate appetite.

Hunger can feel like a gnawing, empty feeling in your stomach and an increase in appetite.

If you become hungry enough, you may even notice that your stomach makes a grumbling noise. For some people, hunger can also be accompanied by:

  • weakness
  • light-headedness
  • disorientation
  • irritability

There are many reasons why you might not feel very hungry, even when your body needs to eat.

Anxiety

When you experience anxiety, your fight-or-flight response kicks in and causes the central nervous system to release certain stress hormones. These stress hormones can slow down your digestion, hunger, and appetite.

People with anxiety disorders may also experience other long-term symptoms, such as nausea, that frequently interfere with normal feelings of hunger.

Depression

Depression can also lead to a long-term decrease in hunger and appetite signaling.

In one small research study, researchers investigated brain images of 16 participants with major depressive disorder who experienced appetite loss.

They found that in these participants, the area of the brain responsible for monitoring the physiological state of the body was less active than their healthy counterparts.

Stress

Stress can cause physical symptoms, like nausea and indigestion, that interfere with your appetite or desire to eat.

In addition, research suggests that your appetite levels can be influenced differently based on the type of stress you experience.

For example, acute stress that activates the fight-or-flight response is more likely to lead to a sudden decrease in appetite and hunger.

Illness

Certain illnesses, like the common cold, seasonal flu, or a stomach virus, can cause a decrease in hunger levels.

Respiratory illnesses, in particular, can block your sense of smell and taste, which can make food seem unappetizing.

In addition, both the seasonal flu and stomach viruses can cause nausea, which tends to decrease your appetite.

Pregnancy

Pregnancy can lead to a decrease in hunger, a loss of appetite, and possibly even food aversions.

Certain pregnancy symptoms, like nausea and heartburn, can make it difficult to sense true hunger levels. In addition, aversions to certain foods can have a negative effect on appetite and hunger.

Certain health conditions

There are a handful of underlying health conditions that can cause you to feel less hungry. Some conditions like hypothyroidism cause the body’s metabolism to slow down, which can lead to a decrease in hunger.

Other conditions that may cause a decrease in appetite include:

Chronic pain

Chronic pain conditions that negatively affect your physical and mental health, like arthritis and fibromyalgia, can cause you to lose your appetite, as well.

This is also part of the reason why some people experience appetite loss during menstruation: The hormonal changes and pain can lead to a decreased appetite.

Medications

Some medications can cause a loss of appetite as a side effect. These medications include:

The decrease in hunger caused by these medications can be accompanied by other side effects that influence hunger levels, such as fatigue and nausea.

Some treatment procedures for certain diseases can also decrease your hunger levels.

One example of this is cancer treatments like radiation and chemotherapy, which are known to decrease appetite. Other procedures, such as peritoneal dialysis, have been shown to cause a loss of appetite as well.

Age

Roughly 15 to 30 percent of older people are estimated to experience age-related appetite decline. There are many reasons why hunger levels decrease with age, including:

  • lower metabolism and energy needs
  • lowered hormone response
  • dampened senses of taste and smell
  • reduced saliva production
  • poor dental health
  • acute and chronic illnesses

Mental health disorders, like anxiety and depression, can also affect appetite in older individuals.

In one cross-sectional study, researchers identified a link between appetite loss and poor cognitive performance in older people with major depression.

If you’ve been experiencing a loss of appetite and a decrease in hunger levels, here are some ways to stimulate your appetite.

  • Make flavorful, delicious meals. If you’re having trouble sparking your appetite, cooking foods with herbs and spices can help you create flavorful meals you’ll enjoy looking forward to eating.
  • Eat smaller meals with more calories. Instead of forcing yourself to eat huge meals, focus on eating smaller meals with more calories. For example, adding whole grains and heart-healthy fats to a meal can boost calories and keep you full for longer.
  • Eat more of the foods you love. Sometimes the best thing you can do for your body when you have no appetite is to eat what you can in the moment. This may not always be a nutrient-dense meal, but not to worry. You can focus on those foods once your appetite returns.
  • Focus on nutrient-dense foods. If possible, try to incorporate nutrient-dense foods, like fruits, vegetables, whole grains, and healthy fats, into your meals. This will help ensure that you’re meeting your nutrient needs with the foods you do have an appetite to eat.
  • Learn to enjoy eating again. Eating is not just for fuel. Sometimes it’s also for enjoyment. When you learn how to enjoy eating again and build positive associations with the act of eating, this can help reignite your appetite for food.
  • Set reminders to eat. With certain illnesses such as depression and anxiety, it can be easy to lose track of our basic needs. Setting a phone alarm for every few hours can help remind you that it’s time to eat a small snack or another meal.

If you notice that your lack of appetite is accompanied by any of the following symptoms, you should visit your doctor, as you may have an undiagnosed underlying condition:

  • finding it difficult to swallow food
  • not eating for long periods of time
  • not being able to keep food down after eating
  • any other symptoms that would indicate a more serious condition, such as pain when eating or food getting stuck in the throat
  • unintentional weight loss

In most cases, your doctor will order some tests to determine if there’s an underlying cause for your lack of appetite.

If there is, your appetite will likely come back over time as you undertake a treatment plan for the underlying condition.

A lack of appetite and a decrease in hunger levels can be caused by a variety of physical or mental factors.

Mental health conditions, like anxiety, depression, and stress, can all have a negative effect on hunger levels.

Other physical conditions, such as pregnancy, hypothyroidism, and more, can also cause a decrease in appetite.

Sometimes even the medications and treatment procedures for certain health conditions can make you lose your appetite.

There are steps you can take to increase your appetite again, including eating smaller meals, cooking foods you enjoy, and setting meal reminders.

If none of these small changes help to improve your appetite or you notice other concerning symptoms, it’s time to visit a doctor to determine if something else is going on.