There are myriad causes of appetite loss, including chronic and acute diseases, eating disorders, reactions to medications, and mental illness, among others. Among the most common are reactions to medications and acute infectious disease. Patients experiencing loss of appetite can use a number of techniques to make sure they get adequate nutrition while the underlying cause is evaluated and addressed. It is important for patients who are not eating well to seek medical treatment, as loss of appetite can be a very serious symptom.
Acute or chronic pain conditions, as well as disorders involving the digestive tract like ulcers and Crohn's disease can be causes of appetite loss. People with dental problems like gum disease and cavities can also experience diminished appetite. Infectious diseases causing nausea and vomiting tend to lead to decreased appetite and wasting diseases like AIDS and cancer are also potential causes of appetite loss. These diseases also cause symptoms like fatigue and anemia.
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Many medications cause patients to lose their appetites. Some drugs cause nausea and vomiting, making it hard for patients to want to eat, and others interrupt the metabolism or endocrine system and make people feel less hungry. Medications known to cause this problem tend to have warning labels alerting patients to this side effect and patients can take steps to address the issue like drinking nutritional shakes and eating nutrition bars to ensure that they get proper nutrition.
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Some recreational drugs are also causes of appetite loss and malnutrition can be a problem among people like alcoholics, who may start eating less as their usage of recreational substances increases. Mental illness and some neurological conditions are causes of appetite loss in some cases; patients with conditions like depression and dementia tend to start eating less. The change in appetite may be gradual, and patients may not be aware of how much their eating habits have changed over time.
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People with diminished appetite tend to naturally lose weight as a result of eating less. Rapid weight loss associated with some medical conditions can be very dangerous and can contribute to stresses on the organs, as well as the immune system. People who are already sick need to be careful about weight loss, as it may make it harder to recover and could put the patient at risk of complications. Steps like eating small meals, avoiding food with strong odors, and keeping nutritious snacks around can help people meet their nutritional needs when they don't feel like eating.