Nausea is a common symptom that all of us experience at some point or the other. Sometimes it is related to a specific disease, usually of the upper digestive tract, but there are instances where nausea may come and go for no clearly identifiable reason. When nausea persists and is accompanied by other symptoms like unrelenting hunger then it needs to be medically investigated.
Feeling of Hunger and Nausea
Hunger is a physiological response of the body that signals a need for feeding. Most of us are familiar with the rumbling sounds emanating from the stomach when we go without eating for a long period. These rumbling sounds are accompanied by strong contractions of the stomach. However, feelings of hunger begin well before the onset of these symptoms.
Also read constant hunger.
Nausea refers to a strong feeling that characterizes the urge to vomit. Nausea is often followed by vomiting. However, this is not so in every case. It is possible that a person may feel nauseous but may not actually vomit. Alternatively, vomiting can occur without any preceding nausea.
The vomiting reflex is initiated when the vomiting centers in the brain are stimulated by certain stimuli, such as gastrointestinal irritation, certain tastes, smells, sounds, and images, as well as movement. The same stimuli can also elicit nausea.
Nausea when hungry
Sometimes, hunger may also elicit nausea. This may be confusing, and a person may associate the nausea with illness rather than hunger. Nausea elicited by hunger may occur before the characteristic rumbling sounds of hunger become audible. These rumbling sounds are caused by strong contractions of the stomach muscles, and are technically referred to as borborygmi.
The churning of stomach that accompanies these sounds is commonly referred to as hunger pangs. The hunger pangs may begin about 12-24 hours after the last meal. Other hunger symptoms, such as constant thoughts about food, excessive salivation, fatigue and lightheadedness, may also occur after the onset of nausea.
Also read headache, nausea and vomiting.
Causes of Nausea and Hunger
The urge to vomit is a sensation that begins in the brain rather than the digestive tract. However, nausea can induce strong contractions of the upper gastrointestinal tract. This results in vomiting. Hunger sensations are stimulated by low blood glucose levels. Nausea may also be stimulated by lower than normal blood glucose levels. This can occur well before the initiation of hunger pangs in the gut. The following are some of the common conditions that may elicit nausea and hunger:
Long intervals between meals is one of the common factors that stimulates nausea and hunger. The popular belief is that one should have three large meals per day. However, this way of feeding leads to large fluctuations in blood glucose levels within the course of each day.
A better alternative is to feed on small quantities of food throughout the day at more frequent intervals. This prevents large fluctuations in blood glucose level. As a result, hunger sensations are not very strong and overeating can also be avoided.
The level of physical activity determines the calorie requirements of an individual. People who are active have a higher daily calorie requirement than people who are comparatively less active. If the amount of food eaten does not provide sufficient calories to an individual, hunger symptoms may arise even when a person is eating regularly.
Taking dieting to the extreme has known health risks. However, people still undertake risky rapid weight loss programs. Trying to ignore hunger, or using substances such as water to suppress hunger can lead to unpleasant symptoms, including nausea. A person will feel hungry as long as the body’s caloric requirements are not met.
The most sensible approach to weight loss is to follow a regular exercise program along with a calorie-restricted diet. However, one does not need to go overboard in terms of food restrictions. Trying to do so will only invite hunger pangs and cause overeating. Eating frequent small meals is a better approach than eating three large meals a day.
Acid reflux refers to a regurgitation of stomach acid and other gastric contents into the esophagus. Gastric acid irritates the esophagus and causes chest pain (commonly referred to as heartburn). When acid reflux occurs persistently over a long period of time, the condition is termed as gastroesophageal reflux disease (commonly abbreviated as GERD). Besides heartburn, acid reflux can also cause nausea. The pain sensation may also be mistaken for hunger.
Gastritis and peptic ulcers
Gastritis refers to inflammation of the walls of the stomach. Peptic ulcers are characterized by the presence of open sores in the walls of the stomach and the duodenum. Gastritis and peptic ulcers can also be the reason behind nausea and hunger sensations. Upper abdominal pain and nausea may also worsen upon food intake.
An overactive thyroid gland (technically referred to as hyperthyroidism or thyrotoxicosis) results in increased concentration of circulating thyroid hormones in the body. The increase in the levels of thyroid hormones stimulates metabolism and increases calorie requirement. This causes the affected person to experience hunger more frequently. Nausea may also be present.
Low blood sugar (technically referred to as hypoglycemia) frequently causes nausea along with other symptoms such as sweating, dizziness, and paleness (also called pallor). These symptoms are most prominent when blood glucose levels become very low.
However, even moderate decrease in blood glucose level can cause nausea. The reason for low blood glucose is not always a lack of food intake. For example, inappropriate use of anti-diabetic medication can also lead to a precipitous drop in blood glucose level.
Drugs and toxins
Many drugs can cause nausea as a side-effect. In fact, nausea is one of the most common side-effects of pharmaceutical drugs. Such drugs stimulate the chemoreceptor trigger zone (abbreviated as CTZ) in the brain, increase production of acid in stomach, and irritate the lining of the stomach wall. Substances other than pharmaceutical drugs, such as illicit substances, poisons, and alcohol can also cause nausea. Gastrointestinal irritation, when accompanied by nausea, may even be mistaken for hunger.
Nausea is a common occurrence during pregnancy. It may or may not be accompanied by vomiting. In most cases, nausea occurs during the first trimester of pregnancy. However, in some women, nausea may continue beyond the first trimester due to increased levels of pregnancy hormones. Acid reflux, which is another common condition in pregnant women, can also cause nausea and hunger sensation. The growth of the fetus in the womb also leads to constant feelings of hunger.
Nausea may also be caused by psychological factors. However, the physical causes of nausea should be ruled out before looking into psychological causes. Anxiety, nervousness, and psychological stress are frequently associated with nausea. Hunger sensations may also arise due to psychological stress. These psychological factors can lead to eating disorders.