What is malnutrition?

  • Malnutrition is a serious health problem. It happens when people do not eat the right amounts of nutrients.

  • Too little food, or a lack of particular nutrients, can cause deficiency diseases or death.

  • Too much food results in obesity. This may cause heart disease or type-2 diabetes.

Find out about the effects and treatment of malnutrition from a UNICEF worker

What is malnutrition?

Malnutrition happens when people do not eat the right amounts of nutrients. Malnutrition can occur all over the world - it is not just a problem in developing countries.

Eating too little food can cause two types of malnutrition:

  • Acute malnutrition - when a person is at immediate risk of dying.

  • Chronic malnutrition - when a person does not grow or develop fully.

Malnutrition can also occur when people eat too much food or large amounts of foods that are high in fat or sugar.

These people may become overweight or even obese. Obesity can lead to life-threatening conditions, including type-2 diabetes, heart disease and some types of cancer.

Deficiency diseases

Some people eat enough food to supply their energy needs, but are short of certain vitamins and minerals. This causes deficiency diseases. For example:

  • Iron deficiency causes anaemia. This leads to tiredness and shortness of breath.

  • Vitamin A deficiency can result in blindness.

  • Vitamin C deficiency causes scurvy, with bleeding gums, bulging eyes and scaly skin.

  • Protein deficiency can affect many body functions, often resulting in swollen, puffy skin and muscle wasting.

Tackling malnutrition

Health and overseas charity workers need to understand nutrition. They use their knowledge to decide whether a person is malnourished. For example, they might use a MUAC band to measure the circumference of a child’s arm. If the arm is too small, the child may have acute malnutrition.

A person with acute malnutrition needs immediate help. This might include giving them life-saving food powder, called ready-to-use therapeutic food, which can be eaten straight from the packet. Ready-to-use therapeutic food is high in energy. It contains large amounts of lipids and carbohydrates.

People with chronic malnutrition also need support. Health and community workers can teach families how to cook nutritious food. Governments can help to make sure that nutritious food is available, and that people are able to grow or buy it.

Where next?

Discover more about this topic from around Bitesize.

What is a healthy diet?
What are lipids, oils and fats?
What are carbohydrates?

Health and disease, there's more to learn...