Loss of appetite means not feeling as hungry as usual, eating less than normal, feeling full quickly, or losing interest in food. It can happen for many reasons: a short viral illness, stress, medication side effects, digestive problems, pain, low mood, pregnancy, ageing, infection, or a more serious underlying condition.
Most short-term appetite changes are not serious. Many people eat less for a few days when they have a cold, flu-like illness, stomach upset, anxiety, pain or poor sleep. Appetite often returns as the body recovers.
However, appetite loss should not be ignored if it is persistent, unexplained, getting worse, or linked with weight loss, difficulty swallowing, vomiting, blood in stool, ongoing pain, fever, night sweats, severe fatigue or a general feeling that something is not right.
This guide explains the common causes of appetite loss in adults and children, what you can try at home, when it may be linked to digestive or mental health problems, what doctors may check, and when to seek medical advice.
Quick answer: A short-term loss of appetite is often caused by viral illness, stress, nausea, pain, medication, tiredness or digestive upset. You should speak to a GP if appetite loss lasts more than a couple of weeks, keeps coming back, causes weight loss, affects a child or older person, or appears with symptoms such as difficulty swallowing, blood in stool, persistent vomiting, abdominal pain, fever, night sweats, severe fatigue or unexplained weight loss.
What does loss of appetite mean?
Loss of appetite does not always mean you cannot eat at all. It can show up in different ways.
You may notice that you:
- do not feel hungry at normal meal times
- eat smaller portions than usual
- feel full after only a few mouthfuls
- skip meals without meaning to
- feel put off by food smells or textures
- feel hungry but become nauseous when eating
- lose interest in favourite foods
- need to force yourself to eat
- are losing weight without trying
The pattern matters. A poor appetite for 2 or 3 days during a cold or stomach bug is different from a gradual appetite decline over several weeks. Appetite loss with clear nausea may point in a different direction from appetite loss with low mood, early fullness, swallowing problems or unexplained weight loss.
If the main issue is tiredness alongside appetite change, you may also find Fatigue: Why Am I Always Tired? useful. If there is weight loss, read Unexplained Weight Loss.
Common short-term causes of appetite loss
Short-term appetite loss is very common and often improves without specific treatment. The body may naturally reduce hunger during illness, stress or inflammation.
Common short-term causes include:
- viral infections, such as colds, flu or COVID-like illnesses
- stomach bugs, including vomiting and diarrhoea
- food poisoning
- fever
- pain, including toothache, sore throat, earache or abdominal pain
- nausea
- stress or anxiety
- poor sleep
- hot weather or dehydration
- alcohol or hangover effects
- recent surgery or hospital admission
- starting a new medicine
If appetite loss comes with fever, body aches, cough, sore throat or blocked nose, it may be part of a viral illness. See Flu-Like Symptoms: Cold, Flu, COVID or Something Else?, Cough in Adults and Sore Throat: Causes and Home Relief.
If appetite loss follows vomiting or diarrhoea, focus on fluids first. Food often comes later. See Diarrhoea and Vomiting in Adults, Vomiting and Diarrhoea in Children, Food Poisoning and What Is Norovirus?.
When appetite loss lasts longer
Persistent appetite loss deserves more attention, especially if there is no clear explanation. It may be caused by a treatable medical problem, a medication side effect, mental health difficulty, nutritional deficiency, chronic infection, digestive disorder, hormone problem, cancer or another long-term condition.
Longer-lasting causes can include:
- depression or anxiety
- ongoing stress or bereavement
- chronic pain
- medication side effects
- acid reflux, gastritis or stomach ulcers
- constipation
- IBS or inflammatory bowel disease
- liver, kidney or thyroid problems
- anaemia or vitamin deficiencies
- diabetes or blood sugar problems
- mouth, dental or swallowing problems
- heart or lung disease causing breathlessness or tiredness
- dementia or frailty in older adults
- cancer or cancer treatment
A useful question is: Is appetite loss the only symptom, or is it part of a wider pattern? For example, appetite loss with nausea suggests one set of causes. Appetite loss with sadness and poor sleep suggests another. Appetite loss with weight loss, early fullness or blood in stool needs more urgent assessment.
Digestive causes: nausea, fullness, reflux and bowel changes
Digestive problems are among the most common reasons people lose their appetite. Sometimes food feels unappealing because eating triggers nausea, pain, bloating, reflux or early fullness.
Possible digestive causes include:
- nausea, which can reduce interest in food even without vomiting
- acid reflux or GORD, especially if eating worsens burning or regurgitation
- gastritis or stomach ulcers
- constipation, which can make the abdomen feel full or uncomfortable
- gallstones, especially if pain follows fatty meals
- IBS, often with bloating, cramps and bowel habit changes
- IBD, such as Crohn’s disease or ulcerative colitis
- coeliac disease
- liver or pancreas problems
- bowel obstruction or serious abdominal illness, which is urgent
Feeling full very quickly after small meals is called early satiety. It can happen with reflux, gastritis, constipation, some medicines, stress, pregnancy and other causes, but persistent early fullness should be checked, especially with weight loss, vomiting, anaemia, black stools or abdominal swelling.
Useful related guides include Nausea: Common Causes and What Helps, Heartburn, Acid Reflux and GORD, Stomach Ulcers, Bloating, Constipation in Adults, Abdominal Pain by Location and Blood in Stool.
Mental health, stress and appetite
Appetite is closely linked to the nervous system, mood, sleep and stress hormones. Some people eat more when stressed. Others lose interest in food completely.
Appetite loss may happen with:
- anxiety
- panic attacks
- depression
- grief or bereavement
- work or family stress
- trauma
- poor sleep
- health anxiety
- eating disorders
With anxiety, appetite loss may come with nausea, a tight stomach, diarrhoea, palpitations, sweating or a sense of dread. With depression, it may come with low mood, loss of pleasure, poor sleep, low energy, hopelessness or neglecting meals.
Appetite changes linked with mental health are real physical experiences, not “just in your head”. But they still need support, especially if you are losing weight, skipping meals frequently, using alcohol or substances to cope, or having thoughts of self-harm.
Related guides include Anxiety Disorder, Panic Attack, Depression, How to Access Mental Health Services in the UK and Online Therapy and Counselling.
Medication, alcohol and treatment side effects
Medicines can affect appetite in different ways. Some cause nausea, taste changes, dry mouth, constipation, reflux, drowsiness or stomach irritation. Others affect mood, hormones or digestion.
Medicines and treatments that may contribute include:
- antibiotics
- painkillers, especially stronger opioid medicines
- anti-inflammatory medicines in some people
- some antidepressants or mental health medicines
- ADHD medicines
- diabetes medicines, including GLP-1 weight loss injections
- iron tablets
- some heart medicines
- chemotherapy, radiotherapy or cancer medicines
- recent anaesthetic or surgery
Do not stop prescribed medicine without medical advice. But do speak to a pharmacist or GP if appetite loss started after a new medicine, dose change or treatment. Sometimes changing the timing, formulation or supportive treatment can help.
Alcohol can also reduce appetite, irritate the stomach, worsen reflux, affect sleep and contribute to poor nutrition. If appetite loss is happening alongside increased alcohol use, it is worth discussing honestly with a healthcare professional.
If you are taking weight loss medicines, see Weight Loss Injections in the UK, Mounjaro vs Wegovy and Are Online Weight Loss Jabs Safe?.
Loss of appetite in children
Children commonly eat less during viral illnesses, teething, sore throats, ear infections, constipation or stomach bugs. A child’s appetite may vary from day to day, and many children eat unevenly across the week.
Short-term appetite loss in children is often less worrying if the child is drinking, passing urine, alert, breathing normally, and gradually improving.
Causes in children can include:
- colds, coughs and viral infections
- fever
- sore throat or tonsillitis
- ear infection
- mouth ulcers
- tooth pain
- vomiting or diarrhoea
- constipation
- anxiety, school stress or change in routine
- food aversion or sensory issues
In children, fluids matter more than food during the first day or two of an illness. Seek advice if a child is not drinking, has fewer wet nappies or is peeing much less than usual, is unusually sleepy, has breathing difficulty, has a non-blanching rash, has severe pain, or has appetite loss that persists.
Useful guides include Fever in Children, Coughs and Colds in Children, Ear Infection in Children, Common Rashes in Children, Chickenpox in Adults and Children and Children’s Teeth.
Loss of appetite in older adults
Loss of appetite in older adults is common but should not be dismissed as “just ageing”. Appetite can reduce with age, but persistent poor intake can quickly lead to weight loss, frailty, falls, weakness, infections, slower wound healing and loss of independence.
Possible causes include:
- loneliness or bereavement
- depression
- dementia or memory problems
- difficulty shopping or cooking
- poor-fitting dentures or dental pain
- swallowing problems
- constipation
- medication side effects
- reduced smell or taste
- long-term heart, lung, kidney or liver disease
- cancer or chronic infection
Warning signs include loose clothing, uneaten meals, an empty fridge, repeated infections, falls, weakness, confusion, dehydration, pressure sores, or struggling to manage food preparation.
If you are worried about an older relative, it may help to read Early Signs of Dementia, Dementia vs Depression vs Mild Cognitive Impairment, What to Do if an Elderly Parent Is Not Safe at Home, Home Care: Types of Support, Funding and How to Choose and Home Care vs Live-in Care vs Care Home.
Weight loss, malnutrition and cancer red flags
Loss of appetite becomes more concerning when it leads to unintentional weight loss or malnutrition. Malnutrition does not only happen in people who are underweight. It can also happen when someone is not getting enough protein, calories, vitamins or minerals for their needs.
Signs that appetite loss is affecting nutrition include:
- unintentional weight loss
- looser clothes, rings or dentures
- weakness
- dizziness
- reduced muscle strength
- tiredness that is not improving
- slow wound healing
- repeated infections
- hair thinning or brittle nails
- low mood or poor concentration
Unexplained appetite loss can also be a red flag when it appears with certain symptoms. It does not automatically mean cancer, but it should be checked.
Speak to a GP promptly if appetite loss is associated with:
- unexplained weight loss
- feeling full very quickly after small meals
- difficulty swallowing
- persistent vomiting
- blood in vomit
- black, tarry stools
- blood in stool
- persistent abdominal pain
- new or persistent change in bowel habit
- ongoing cough, coughing blood or breathlessness
- night sweats or unexplained fever
- new lump or swollen lymph nodes
- severe fatigue or anaemia
- jaundice, meaning yellow skin or eyes
Related guides include Unexplained Weight Loss, Blood in Stool, Swollen Lymph Nodes, Night Sweats, Iron, Ferritin and Anaemia Blood Test Results, Full Blood Count Results and How to Understand Blood Test Results.
What a GP may check
If you speak to a GP about loss of appetite, they will usually start by asking about the pattern, duration and associated symptoms. Try to be specific. “I have eaten half my usual amount for three weeks and lost 4 kg” is more useful than “I’m not eating much”.
A GP may ask about:
- how long appetite loss has been present
- whether it started suddenly or gradually
- weight change
- nausea, vomiting, reflux or swallowing problems
- bowel habit changes
- abdominal pain or bloating
- fever, night sweats or infections
- mood, anxiety and sleep
- medicines, alcohol and recreational drugs
- dental problems or mouth pain
- recent travel or infection exposure
- family history and cancer risk factors
Depending on symptoms, checks may include:
- weight and BMI
- temperature, pulse and blood pressure
- abdominal examination
- mouth and throat examination
- lymph node examination
- blood tests such as full blood count, liver, kidney, thyroid, inflammation markers, HbA1c, iron, B12 or folate
- urine test
- stool test
- chest X-ray
- ultrasound, CT, MRI, gastroscopy or colonoscopy if needed
If tests are arranged, these guides may help: How to Understand Medical Test Results, Urine Test Results Explained, Liver Function Test Results, Kidney Blood Test Results, Thyroid Blood Test Results, Abdominal Ultrasound, CT Scan, Gastroscopy and Colonoscopy.
What can help when you do not feel like eating?
What helps depends on the cause. If appetite loss is due to a short illness, the aim is usually to stay hydrated and eat small amounts until appetite returns. If appetite loss is persistent, worsening or causing weight loss, it should be assessed rather than managed only with self-care.
Practical steps that may help include:
- eat small, frequent meals rather than large plates
- choose soft or easy foods if chewing or swallowing is difficult
- try bland foods if nausea is present
- drink fluids regularly
- try nourishing drinks such as milk, smoothies or soups if solid food feels difficult
- add calories with olive oil, nut butter, cheese, yoghurt, avocado or cream if weight loss is a concern
- eat when appetite is best, even if that is not a normal meal time
- keep easy snacks nearby
- avoid strong smells if they worsen nausea
- eat with someone else if loneliness affects meals
- treat constipation, reflux, pain or nausea if these are reducing appetite
- ask a pharmacist about medicine side effects or safe symptom relief
If you are losing weight or struggling to eat enough, do not rely only on “healthy eating” advice. Sometimes the priority is getting enough calories, protein and fluids, even if meals are smaller or more energy-dense than usual.
If cancer or cancer treatment is involved, Macmillan has practical advice on eating problems and appetite loss. Macmillan: eating problems and cancer.
When to seek medical advice
Speak to a GP if appetite loss:
- lasts more than 1 to 2 weeks without a clear reason
- keeps coming back
- is getting worse
- causes unintentional weight loss
- affects an older person, child or someone with a long-term condition
- starts after a new medicine or treatment
- is linked with persistent nausea, reflux, abdominal pain or bowel changes
- comes with low mood, anxiety or difficulty coping
- is causing weakness, dizziness or poor fluid intake
Seek urgent medical advice if appetite loss comes with:
- severe abdominal pain
- persistent vomiting or inability to keep fluids down
- blood in vomit
- black, tarry stools
- blood in stool
- difficulty swallowing or food getting stuck
- chest pain or severe breathlessness
- confusion, collapse or severe dehydration
- yellow skin or eyes
- rapid unexplained weight loss
- fever with a very unwell appearance
- thoughts of self-harm or not wanting to live
Call 999 if there is severe chest pain, severe breathing difficulty, collapse, severe confusion, signs of stroke, severe dehydration, heavy bleeding, or symptoms that feel like an emergency.
For access advice, see How to Get a GP Appointment Quickly, When to See a Pharmacist Instead of a GP and Private GP Services in the UK.
Frequently asked questions
Is loss of appetite serious?
Short-term appetite loss during a cold, stomach bug, stress or mild illness is usually not serious. Appetite loss becomes more concerning if it lasts, gets worse, causes weight loss, or comes with symptoms such as pain, vomiting, blood in stool, difficulty swallowing, fever, night sweats or severe fatigue.
How long can loss of appetite last after a virus?
It can take a few days for appetite to return after a viral illness. Some people take longer, especially after flu-like illness, COVID, stomach bugs or fever. If appetite does not gradually improve, or you are losing weight, speak to a GP.
Can anxiety cause loss of appetite?
Yes. Anxiety can reduce appetite and cause nausea, a tight stomach, diarrhoea, palpitations or feeling unable to eat. If anxiety is frequent, affecting meals or causing weight loss, it is worth seeking support.
Can depression cause appetite loss?
Yes. Depression can reduce interest in food, motivation to cook, appetite and enjoyment of meals. Some people lose weight. Others eat more. Appetite change with low mood, poor sleep, hopelessness or loss of pleasure should be discussed with a healthcare professional.
Why do I feel full after only a few bites?
Feeling full quickly can happen with reflux, gastritis, constipation, stress, pregnancy, some medicines and other causes. Persistent early fullness, especially with weight loss, vomiting, abdominal pain, anaemia or black stools, should be checked.
Can constipation reduce appetite?
Yes. Constipation can cause bloating, fullness, nausea and reduced appetite. Treating constipation may improve appetite, but persistent symptoms or red flags should still be assessed.
Can medication cause loss of appetite?
Yes. Antibiotics, painkillers, diabetes medicines, ADHD medicines, some antidepressants, iron tablets and cancer treatments can affect appetite. Speak to a pharmacist or GP if appetite loss started after a new medicine or dose change.
What should I eat when I have no appetite?
Try small, frequent meals or snacks. Soft foods, soups, yoghurt, smoothies, milk, eggs, porridge, toast, rice, pasta, bananas and simple meals may be easier. If losing weight, add nourishing, higher-calorie options and ask for medical advice.
Should I force myself to eat?
During a short illness, fluids are often more important than forcing food. Try small amounts regularly. If appetite loss is lasting, causing weight loss or linked with worrying symptoms, seek medical advice rather than simply forcing meals.
When should I worry about appetite loss and weight loss?
You should speak to a GP if you are losing weight without trying, especially if appetite loss is persistent or linked with tiredness, pain, bowel changes, swallowing problems, vomiting, blood in stool, night sweats, fever or a new lump.
Can dehydration cause loss of appetite?
Yes. Dehydration, hot weather, fever, vomiting and diarrhoea can reduce appetite. Signs include thirst, dark urine, dizziness, dry mouth and peeing less. Severe dehydration needs urgent advice.
Can dental problems affect appetite?
Yes. Toothache, mouth ulcers, gum disease, dentures, dry mouth or difficulty chewing can reduce appetite. Dental problems should be treated, especially in older adults or people losing weight.
Is appetite loss a cancer symptom?
It can be, but it has many other causes too. Persistent unexplained appetite loss, especially with weight loss, early fullness, difficulty swallowing, blood in stool, abdominal pain, night sweats or severe fatigue, should be checked.
What tests might a GP do for loss of appetite?
Depending on symptoms, a GP may check weight, examine your abdomen, review medicines and arrange blood tests, urine tests, stool tests, chest X-ray, ultrasound, CT, gastroscopy or colonoscopy.
What if an older person is not eating?
Do not dismiss it as normal ageing. Check for dental pain, swallowing problems, constipation, depression, dementia, medication side effects, loneliness and difficulty shopping or cooking. Seek GP advice if intake is poor, weight is falling or there are signs of frailty or dehydration.
