Overview
Appetite is the want to fulfil your body’s needs to provide energy for your daily activities. Appetite can be divided into three components, hunger, satiation and satiety.
The process of appetite is a complex reaction. The appetite is controlled by the brain, digestive system, endocrine system and sensory nerves.
There are many factors that trigger appetite. When you tend to smell your favourite food or a tasty treat that stimulates your taste buds. The colour of the food that triggers you to eat food. Even when you are not hungry certain foods stimulate your appetite.
Mood also plays an important role in a person's eating habits. People eat food when they are happy or sad. Some eat desserts when they are happy, some prefer junk food when they are sad to improve their mood. And a few skip meals when they are sad.
On the other hand, people restrict their eating habits for various reasons like weight loss and to maintaining weight. According to PMC8759923, 93% of patients in India have a loss of appetite with severe illness.
Loss of appetite is the decreased or reduced desire to eat. In medical terms, it is called anorexia. There are many reasons that cause loss of appetite. The reasons may be due to physical illness, mental health, desire to lose weight or maintain weight, the smell of food, the place of food served, smoking and age of the person.
Causes of decreased appetite
Reduction in appetite can leads to reduced food intake and nutrients. Loss of appetite increases the risk of unhealthy weight loss and nutritional deficiencies. Ageing also plays an important in decreased appetite.
According to PMC4589891, about one-third of elderly people aged 65 have reduced saliva production. As a result, people will find it difficult to eat and there will be a loss in appetite.
- Bacteria and virus
Loss of appetite may be due to infections caused by bacteria and viruses. This is called sickness-associated anorexia (SAA).
When the body encounters an infection, there will be certain reactions from our body. The antibodies will be alerted and expansion of immune cells will take place.
When there is an established infection, loss of appetite manifests indicating cardinal symptoms of the bacterial or viral invasion.
There are three theories that support the sickness associated anorexia (SAA) as an adaptive response.
Non-infectious foreign particles like lipopolysaccharides or cytokines like IL-1β (Interleukin 1 beta) and TNF-α (Tumour Necrosis Factor-alpha) can induce loss of appetite.
An array of animals including, vertebrates to invertebrates exhibit a loss of appetite when there is a pathogen invasion.
Almost, every sickness induces loss of appetite except African horse sickness, during an infection caused by bacteria or virus.
According to PMC4942670, there are few observations that support the view that SAA is a dedicated host response that facilitates host survival during infection. However, the survival advantage remains elusive.
Another theory suggested that free iron is rapidly reduced during an infection. It is said that chronic low iron levels might provide a pleiotropic benefit by protecting the host against infections. Accordingly, an anorexic response may deny pathogens with critical resources such as iron.
- Psychological causes
Your mood plays an important role in your eating habits. Some people eat less or eat more when they are unhappy. Depression is one of the major reasons for loss of appetite and also overeating.
According to PMC4818200, approximately 48% of adults are exhibiting loss of appetite due to depression, whereas, 35% of adults exhibit increased appetite due to depression.
Research suggests that depression-related appetite changes can be indicative of underlying neural and inflammatory differences among major depressive disorders (MDD).
- Medical conditions
Medical conditions such as pregnancy, metabolic problems, liver diseases, HIV, hypothyroidism, kidney problems and COPD can cause loss of appetite.
Short-term medical conditions like cold and flu, respiratory infections, constipation, diarrhoea, digestive issues and stress can cause loss of appetite.
According to PMC6164971, Loss of appetite is less common in patients with Alzheimer’s dementia, with or without depression.
Loss of appetite is one of the predominant symptoms of cancer. It can indicate cancers like ovarian cancer, pancreatic cancer or stomach cancer.
- Medications
Certain medications suppress your hunger and reduce your appetite. These medications are called appetite suppressants.
Appetite suppressants work as weight-loss medications. These appetite suppressant drugs control your brain’s urge to eat or make you feel full with little quantity of food. As a result, there will be very less calories consumed and you lose weight faster.
Drugs like diethylpropion, liraglutide, naltrexone-bupropion, Phendimetrazine, Phentermine and Phentermine/topiramate are approved appetite suppressants by the Food and Drug Administration (FDA).
Loss of appetite is also a side effect of certain medications. Sedatives, some antibiotics, chemotherapy drugs and immunotherapy drugs can cause loss of appetite.
Symptoms of poor appetite
- Weight Loss
Loss of weight is the primary symptom of reduced appetite. When you don’t eat well, there will be nutrition deficiency and your body will find it difficult to use calories for your daily activities. As a result, there will be weight loss.
- Depression
Loss of appetite can be indicative of depression. It can be an early sign of depression and a warning for depression relapse.
Depression alters your eating habits. Some people tend to eat less whereas, others eat more.
Depression that increases your eating habits is associated with hyperactivation of putative mesocorticolimbic reward circuitry whereas, depression that leads to loss of appetite is associated with hypoactivation of insular regions that support monitoring the body’s physiological state.
According to PMC4818200, depression disorder is the major cause of chronic disability and mortality worldwide.
- Loss of taste sensation
Loss of taste sensation is common as you age. But when the taste sensation decreases when you are young, it might be indicative of loss of appetite.
Consumption of food takes place with the smell and colour of food. When you lose the sensation to smell. The consumption of food decreases.
Further, when you lose the taste sensation your eating habits may change and you start to consume less food. As a result, there will be a loss of appetite and weight loss.
Loss of taste sensation can be indicative of other medical conditions like viral infection, coronavirus, Alzheimer's disease and Parkinson's disease.
Loss of taste sensation can affect your quality of life. These sensation losses can tempt you to consume foods with excess amount of salt and sugar. It can lead to risk factors like diabetes and high blood pressure.
Loss of smell and taste sensation can be indicative of coronavirus, as suggested by World Health Organisation (WHO).
Treatments for poor appetite
Loss of appetite can be treated with few lifestyle changes. Do not take any over-the-counter drugs for loss of appetite without consulting your doctor.
- A better sleep schedule
A common hypothesis states that there is a connection between your sleep cycle and appetite. We often think of appetite as simply a matter of stomach grumbling but it is controlled by neurotransmitters. Neurotransmitters are chemical messengers that allow neurons to communicate with one another.
The neurotransmitters ghrelin and leptin play an important role in appetite. Ghrelin promotes hunger, and leptin suppresses the feeling of hunger. The body naturally fluctuates the levels of these neurotransmitters throughout the day, signalling the need to consume calories.
A lack of sleep may affect the balance of neurotransmitters. A study was conducted with, men who got 4 hours of sleep had increased ghrelin levels and decreased leptin levels compared to those who got 10 hours of sleep.
The imbalance in the ghrelin and leptin causes people to eat more and increases their appetite and decreases the feeling of fullness.
In addition, several studies suggested that sleep-deprived individuals tend to choose foods that are high in calories and carbohydrates.
Many doctors and researchers believe that the connection between sleep and the imbalance of neurotransmitters is complicated and additional studies are needed to further understand the neurobiological relationship.
- A special diet that will help maintain proper nutrition
Avoid drinking water before meals. Sometimes, a short walk before meals may make you feel hungry and you will be able to eat well.
Always have a high-protein snack handy. Foods like boiled eggs, peanut butter, cheese, ice cream, nuts and chicken may help you get the nutrients your body will need.
Do not go without eating for more than 3 hours. Try to have small snacks in between to keep your appetite well balanced. Have foods that are easy to make or require little to no preparation. Nuts and dried fruits may give the energy your body requires.
Keep your foods visible so that they you will get a temptation to eat. This might help you eat well. Include fruits and vegetables like carrots, watermelon, grapes, apple, mango, papaya, pomegranate and banana. You can also make a fruit salad to increase your appetite.
If the foods are not appealing to you, try some beverages that contain nutrition. Protein shakes, milkshakes, or a smoothie may have calories as much as a small meal or a snack. Make sure you don’t drink any liquids before meals. It might reduce your meal consumption. You can have these drinks in between your meals.
- Improved self-care
Take pleasure in eating food with your family and social members. Cook your favourite foods to promote appetite. Go out to restaurants, this might help you to eat well.
- Increased physical activity
Make it a habit to exercise every day for half an hour. This will kindle your hunger sensation and might help you to eat well. Physical exercise is usually advised for people to counteract obesity.
Physical activity increases your energy expenditure and lowers your energy balance. When energy is used for physical exercise, it elevates the intensity of hunger and increases the sensation to eat.
- Medication to increase your appetite
Meditation does not directly increase your appetite but it helps in mindful eating. Chronic stress can also be a cause of loss of appetite. When you meditate it might reduce your stress and promotes appetite.
On the other hand, emotional eating is when people tend to eat more. Mindful eating is a technique that helps to repair your eating habits. This technique engages your senses and makes you eat well.
- Talk therapy
Talk therapy works on the core idea that when you talk out the things that bother you it helps to reduce emotional distress. Talk therapy is also called as psychotherapy.
The treatment will have sessions depending on your requirement. You will have to visit the professional until you have been relieved from the problem.
Diagnosis of poor appetite
- Physical exam
There is a certain procedure followed for the diagnosis of loss of appetite. The doctor will analyse the duration of anorexia followed by a physical examination.
The doctor might examine your abdominal examination to check for lumps, distension, tenderness and free fluids. The weight check will be the primary physical examination.
Other signs like knuckle ulcers, loss of teeth and enamel calluses will also be checked.
- Laboratory test
The laboratory test will be followed by a physical examination. The laboratory test will include total blood count, liver and kidney function test, thyroid test and urinalysis.
- Psychological assessment
The psychological analysis will usually contain a set of questions about your behaviour, eating habits, favourite foods, about your routine, binging and body image.
When to visit a doctor?
When the loss of appetite is for a prolonged time, it leads to weight loss and malnutrition. A person must visit a doctor when there are visible signs like
- Fever
- Stomach pain
- Irregular heartbeat
- Cough and
- Shortness of breath.
Conclusion
Loss of appetite may be due to various reasons like stress, infection, allergies and other medical conditions. Loss of appetite may lead to unhealthy weight loss and affects the quality of life.
Small steps can help with appetite loss. Exercise helps to burn calories and increases your hunger sensation.
Try eating small meals rather than big three meals a day. Always drink fluid to avoid the risk of dehydration.
FAQ
1.How do I fix my poor appetite?
Add more cereals to your diet so that there will be protein addition. Schedule your meal times and stick to them. Try to trick your brain with different plate sizes. Never skip your breakfast and limit your fibre intake.
2.What are the three factors that affect appetite?
3.What stimulates loss of appetite?
4.How do I get my appetite back?
Consume foods like eggs, milk, poultry, fish, beans, nuts and cheese. Protein-rich meals may help to increase your appetite.
