Malnutrition – Types, Causes, and Symptoms


Malnutrition refers to getting minimal or excessive nutrients from various sources.

It is a condition that develops when the body is deprived of essential vitamins, minerals or other nutrients that are required to maintain healthy tissues and enable smooth functioning of the body.

Malnutrition can occur in people who are undernourished and also overnourished. Affecting many people across the globe, malnutrition is developed based on the lifestyle, environment or access to various resources.

What is malnutrition?

Malnutrition is a health condition that arises when nutrition is deficient in the body. Undernutrition occurs when a person doesn’t consume enough essential nutrients. Overnutrition happens when people overeat and take too many vitamins.  

What are the types of malnutrition?

The types of malnutrition include


Undernutrition is when a person is deprived of protein, micronutrients or calories, leading to low weight and height, causing stunted growth.


Overconsumption of certain nutrients like fat, protein or calories can lead to malnutrition resulting in overweight or obesity.

Malnutrition can be further divided into two types. They are,

Micronutrient undernutrition

Micronutrient undernutrition, also called protein-energy undernutrition, is a deficiency of macronutrients like proteins, carbohydrates, or fat.

These macronutrients play a significant role in the body and act as the building blocks of the diet. These are the nutrients that the body depends upon to produce energy.

Micronutrient malnutrition

Vitamins and minerals are called micronutrients which serve as the building blocks for good health. People who are deprived of these nutrients are classified as micronutrient malnutrition.

This health condition can be devastating and cause consequences like congenital disabilities, poor cognitive ability and other chronic illnesses.

People who are undernourished are usually deprived of vitamins and minerals like iron, zinc and iodine. Micronutrient deficiencies can also occur when there is over nourishment.

What are the signs and symptoms exhibited by a malnourished person?

The symptoms of malnutrition depend on the type of condition.

The ability to recognise the side-effects of malnutrition can help people to treat it accordingly.

What causes malnutrition?

Malnutrition is a global concern that arises from various factors like environmental, economic and medical conditions.

Some of the common causes of malnutrition include

Lack of access to food

The scarcity of food has a direct link to developing malnutrition. Shortage of food affects countries. It is a problem that organisations like WHO and UNICEF address.

Digestive problems

Digestive problems or health conditions that can cause malabsorption, make it difficult for the body to absorb nutrients. Bacterial overgrowth in the intestine can also result in malnutrition.

Mental health disorders

Mental health disorders like depression or other conditions can increase the risk of developing malnutrition


Excessive alcohol can lead to inadequate protein intake, calories and micronutrients. Apart from increasing the chances of developing malnutrition, alcohol is a threat to a person’s overall health.

Low intake of food

The most common malnutrition factor is low food intake and the inability to obtain or pick up food. Poor mobility and muscle strength can also be risk factors for malnutrition.

Symptoms of undernutrition

Undernutrition can make a person exhibit

  • Weight loss
  • Muscle loss
  • Fat loss
  • Hollow cheeks
  • Swollen stomach
  • Dry hair
  • Dry skin
  • Sunken eyes
  • Delayed wound healing
  • Difficulty in concentration
  • Irritability
  • Fatigue
  • Depression and
  • Anxiety.

People suffering from undernutrition can exhibit one or more symptoms. It can also result in micronutrient deficiencies that can make a person exhibit symptoms like

  • Dry eyes and night blindness due to lack of vitamin A
  • Loss of appetite, delayed wound healing and hair loss due to a lack of zinc in the body.
  • Cognitive health decline, impaired brain function, stomach problems are exhibited when there is a lack of iron.

Undernutrition is a dangerous health condition that can increase the chances of death.

A doctor assesses malnutrition symptoms when they check for the health condition. A healthcare provider will use specific tools to identify malnutrition, including weight loss blood tests, physical examinations and body mass index.

Malnutrition can also have some long-term effects on the body. It can lead to the development of certain diseases and chronic health condition that includes the risk of obesity, heart disease and diabetes.

Malnutrition can also trigger health issues like heart disease and type 2 diabetes.

How is malnutrition diagnosed?

Most malnutrition defects are diagnosed with the help of body mass index. The body mass index is calculated by the weight in kilograms and divided by the height in metres.

A healthy BMI for adults is usually between 18 and 25. People with a BMI score of 17 or lower can be considered malnourished.

Blood tests or general screening tests on a patient can help diagnose malnutrition. Also, specific test to diagnose for vitamin deficiencies is done to know if the body is deprived of certain nutrients that can help identify malnutrition.

A doctor can also prescribe an albumin test indicating liver or kidney diseases. With the help of these diagnoses, a doctor can provide treatment accordingly.

How to prevent or treat malnutrition?

Preventing or treating malnutrition involves addressing the underlying cause of the health condition.

Various research suggests that the most effective ways to prevent malnutrition include iron, zinc, iodine or other food supplements that can provide nutrition and avoid the risk of undernutrition.

As malnutrition is caused by a lack of essential nutrients in the diet, the treatment mainly depends on treating the underlying cause.

A diet plan can help patients to enhance their diet and improve nutrient intake.

The intake of protein, carbohydrates, vitamins, minerals and water would gradually be increased. Usually, for malnutrition, supplements of the deficit minerals or vitamins are advised.

People with protein-energy malnutrition are advised to consume protein bars or other supplements to correct the deficiency.

A general malnutrition standard is studied with the help of body mass index that is used to monitor and check for improvement.

A team of doctors or healthcare providers can manage malnutrition patients with the help of a gastroenterologist who specialises in treating various digestive conditions.

Treating malnutrition involves individualised approaches. A doctor would assess the signs and symptoms of undernutrition, recommend various interventions, and help the person improve their health.

Even if some patients cannot take food through their mouth, they will be fed with the help of artificial tubes inserted via the nose to the stomach.

Some people with undernourishment can be given nutrients with the help of injections that are directly infused into the veins of the arms.

How to prevent malnutrition?

A healthy diet is essential to prevent malnutrition.

Some of the essential foods to include prevent undernutrition are

  • Carbohydrates from starchy food like bread and potatoes rice provide calories for energy.
  • Milk and other dairy products for calcium
  • Fruits and vegetables that provide adequate vitamins and minerals to improve the overall health
  • Lean protein like meat, poultry, eggs, fish and beans serve as the body’s building blocks and help with enzyme functions.
  • Engaging in moderate physical activity can also help improve a person’s overall health.

What can increase the chances of malnutrition?

  • Being in a hospital
  • Having a chronic illness like Diabetes or cancer
  • Dental problems
  • Loss of smell and taste
  • Some of the side effects of medication
  • Physical disability and
  • Poor appetite can increase the chances of malnutrition.

To sum up

Malnutrition can be overnutrition or undernutrition. Undernourished people can experience weight loss and other vitamin or mineral deficiencies.

People with overnutrition are usually obese and overweight, leading to inadequate absorption of micronutrients in the body.

If both types of health issues are not appropriately addressed, it can lead to complex health conditions that can be fatal.

It is essential to talk to a doctor and get treated immediately if a person exhibits symptoms of malnourishment.


What are the possible questions about malnutrition?

Some of the questions about malnutrition are
1. How does poverty lead to malnutrition?
2. Why do children suffer from malnutrition?
3. Why do malnourished children have big bellies?
4. What is the main problem of malnutrition?

What are the four consequences of malnutrition?

The consequences of malnutrition are
1. Weight loss and loss of muscle function
2. Cardiorespiratory dysfunction
3. Gastrointestinal dysfunction
4. Poor immunity and wound healing and
5. Negative psychosocial effects.

What are the five risks of malnutrition?

1.  Poor oral health
2. Polypharmacy
3.  Depression
4.  A strict therapeutic diet and
5. Cognitive impairment are the risk factors for malnutrition.

What prevents malnutrition?

The best way to prevent malnutrition is by consuming a healthy diet that includes fruits and vegetables, starchy food and lean protein.

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