What is malnutrition?

Malnutrition occurs when insufficient food has been eaten so that the body starts to use up its own reserves of energy and protein. Your reserves of sugar, fat and protein become depleted. This leads eventually to potentially severe consequences.

Is malnutrition a common problem?

You may think of malnutrition as something that occurs in so called developing or third world countries, particularly in Africa or India. It is true that malnutrition is quite common in those areas but it is also surprisingly common in the UK. Up to 40% of those admitted to hospital in the UK already show evidence of malnutrition. The reasons for finding malnutrition in the UK do not relate to shortages of food but to the effect of underlying illnesses, and/or poverty and social deprivation. Obesity is also due to poor nutrition but in this article, malnutrition refers only to those suffering from undernutrition, not excess nutrition.

Malnutrition actually costs the UK more each year than obesity! It has been calculated that up to 3 million people are suffering from malnutrition in the UK. Could you be one of them?

You already know you have an underlying condition such as Crohns disease…

In this case, your ability to eat enough to satisfy your body’s requirements is likely to be impaired. Often, such patients run along with their weight much lower than it should be or was before your illness. This situation can become accepted as the “norm” by the patient, relatives and even their doctors. This is why it is so important to think of malnutrition so that once recognised, it can be treated properly. The measures available to treat malnutrition are beyond this article but in brief, attention to the type of food you are able to eat or addition of oral supplements under the guidance of a properly qualified dietitian may be enough to restore your nutritional status to normal. If not, more aggressive measures may be required. These include feeding you via a small tube passed through your nose or tummy wall into the stomach or intestine. In a minority of difficult cases, intravenous nutrition is required. This is not always offered as often as it should be because local hospitals do not always have the experience or expertise to offer it or to do it properly. Asking your hospital doctor or GP for referral to the hospital nutrition team or to a specialist centre can be difficult but if you are clearly undernourished and not getting any better, this may be just what is needed to help you “turn the corner”. Surgeons who offer a non emergency abdominal operation when you have untreated malnutrition are best avoided.

There are many disease processes which are associated with deteriorating nutrition. For example: chronic chest diseases, heart failure, kidney and liver failure and numerous abdominal causes, strokes and other disorders of the nervous system.

In some distressing disorders, difficulties swallowing can be anticipated as the disease runs its course. In such cases, it is important that you discuss the future with your family and doctors. If necessary, it is strongly advised that you make an “Advanced Directive” to guide your family and doctors when the situation is no longer under your control.

What not to do if you are worried about malnutrition…

Don’t ignore it!
  • Don’t seek advice from so called nutritionists or complimentary medicine practitioners on the high street.
  • Don’t regard malnutrition and weight loss as an inevitable consequence of your underlying condition, even cancer.
  • Don’t ignore it or be embarrassed if you have any concerns bring up the subject with your GP or hospital doctors.
  • Don’t forget to make sure you are weighed when you visit hospital as a patient.
PINNT is here to support you and steer you in the right direction but primarily we are here to support you should and when artificial nutrition is commenced if it’s what you need.
PINNT would like to thank Dr Barry Jones for compiling this information.

What problems occur with malnutrition?

As your reserves of fat and muscle decline, you may experience general weakness, fatigue, difficulty working or doing simple jobs about the house. You may notice the cold more as your insulating layers of fat disappear. Sleep patterns may be disturbed.

Cuts or wounds and fractured bones may not heal properly or as quickly. You may be at increased risk of infections such as pneumonia.

In children or adolescents, growth or puberty may be affected. Milestones may be delayed.

Women of menstruating age may experience menstrual disturbances or cessation of periods altogether. Infertility often occurs as a protective mechanism when women become malnourished. This can be reversed with good nutrition.

Older people often become dependent on others for basic care such as getting up out of a chair, going to the toilet or getting up stairs but these problems are far more common when old people have become undernourished. Falls and fractured hips and wrists are more common as muscles no longer support weight and bones become more brittle (osteoporosis). Bed sores may also develop due to immobility and undernutrition, particularly if confined to bed or a chair.

If you have undergone surgery or have been the subject of trauma, your recovery is likely to be prolonged unless measures are taken to remedy your lack of adequate nutrition before and after the event. Surgical wounds and “join ups” of the bowel inside you may not heal at all unless nutritional support has been given before the operation.

Symptoms of specific deficiencies may also become apparent - see table below.

Your response to certain drugs/medications may be affected for example Warfarin which may become more powerful causing poor anticoagulant control and bleeding. You may also notice that alcohol has a more potent affect on you than before.

Liver dysfunction may occur and enlargement of the liver due to fat within it is sometimes found.

Swelling of the ankles (oedema) is common in malnutrition. Abdominal swelling is found in severe cases of malnutrition due to accumulation of fluid within the abdominal cavity (ascites).

Lack of adequate nutrition can also lead to deficiencies of specific nutrients such as vitamins or other essential substances. Sometimes, the first evidence of malnutrition is a specific deficiency disorder such as one of those shown in table below.
Deficiency Disease name Appearances /symptoms
Vitamin A Xerophthalmia Night blindness
Vitamin B1 (thiamine) Beri-beri
Wernicke-Korsakov syndrome
Shortness of breath due to heart failure; numbness and tingling of hands and feet. Impaired consciousness and brain function
Vitamin B2 (riboflavin)   Cracked lips/ sore tongue
Vitamin B3 (niacin) Pellagra Rash on sun exposed skin; diarrhoea
Vitamin B6 (pyridoxine)   Depression; Premenstrual tension
Vitamin B12(cyanocobalamin) Pernicious anaemia/ sub-acute combined degeneration of the cord/Peripheral neuropathy Numbness and tingling of hands and feet; fatigue and shortness of breath due to anaemia; visual disturbances.
Vitamin C Scurvy Bleeding gums, swollen painful joints; bleeding; mental disturbances; impaired wound healing
Vitamin D Rickets/osteomalacia Painful bones, fractures, impaired growth
Vitamin E   Anaemia in infants; heart and muscle disorders; numbness and tingling in hands and feet
Vitamin K Hypoprothrombinaemia Bruising/easy bleeding
Folic acid Anaemia Tiredness, shortness of breath
Essential fatty acids   Skin rash
Calcium Hypocalcaemic tetany Painful muscle spasms; impaired consciousness
Magnesium Hypomagnesaemic tetany Painful muscle spasms; impaired consciousness
Potassium Hypokalaemia Muscle weakness; palpitations; bowel dysfunction
Sodium Hyponatraemia Muscle cramps; dizziness; collapse; confusion
Zinc   Thrush like rashes, peeling skin rashes, diarrhoea, impaired immunity
Iron   Anaemia, fatigue, sore tongue, blue sclera, difficulty swallowing (rare). Dry skin and poor hair quality.
Selenium   Heart failure; muscle weakness
Copper   Anaemia
Various deficiencies associated with malnutrition
If you or perhaps a family member or carer are worried that you are developing malnutrition, the first thing to consider is whether you have lost weight without trying to diet.

If you haven’t weighed yourself recently, but have noticed your belt, skirt, trousers, or collar becoming loose? This may be a sign that you are not receiving enough nutrition. There are various discussions over what malnutrition looks like, with a historic emphasis on weight and weight loss; with a 5% unintentional weight loss indicating a risk of malnutrition and an unintentional weight loss of 10 or more, being considered an indicator of malnutrition. So, this would mean that someone who is 10 stone (63.5kg), would be considered to be at risk if their weight dropped (without trying) to 9 stone 7 (60.3kg) or to be a high risk with a weight change to 9 stone (57kg). However, solely basing malnutrition on weight and Body Mass Inde (BMI), is not recommended as a more comprehensive assessment is needed to ensure that no cases of malnutrition are missed. It has been shown that people living with obesity (a BMI>30kg/m2) can become malnourished and be at risk of developing the medical complications associated with it. This is because if there is a loss of muscle protein the health of the person can become at risk.

The quicker weight is lost, the more problems may become apparent. These problems may be noted before you have realised that you have lost weight.

Most people will note that they have not been able to eat so much before their weight begins to fall.

Healthcare professionals have developed a “Tool” to measure your risk of malnutrition. This is called the “MUST” tool. This stands for “Malnutrition Universal Screening Tool”, available on the British Association of Parenteral and Enteral Nutrition (BAPEN) website at

If you have lost between 5 -10% of your original body weight unplanned, and have an acute illness likely to prevent you from eating properly for more than 5 days, you will score highly enough to be considered at risk of malnutrition without attention to your nutritional needs.

If your BMI (Body Mass Index – calculated by dividing the square of your weight in kilograms by your height in centimetres) is already in the low range of less than 20, and especially if it is less than 18.5, your risks are even greater. This means that without attention to your needs, you have little room for manoeuvre if your illness does not resolve quickly and your ability to eat normally has returned. Malnutrition then becomes an additional risk factor which might delay your recovery or affect your ability to cope with the stress of your illness or surgery.
Good nutrition is important to everyone but crucial to those with disease-related malnutrition or recovering from surgery. The body will then be working extra hard to restore good health, thus increasing nutritional needs.
It is the role of your medical team to ensure that you are well nourished and not suffering from malnutrition (a condition resulting from the body not getting the right amount of vitamins, minerals, and other nutrients needed to maintain health). One method of assessment is the “MUST” tool which determines presence or risk of developing malnutrition (shown below). The tool uses a points system to assign the appropriate level of intervention and / or monitoring.

Malnutrution Universal Screening Tool, British Association of Parenteral and Enteral Nutrition (BAPEN)

Once this has been determined your medical team is then required to ensure that you are able to meet your nutritional requirements and if not why this may be. For most people this can simply be achieved with a small increase or supplementation to their oral intake. However, if a patient has a problem with their digestive system and/or their condition results in an inability to fully meet their individual requirements for the essential nutrients it may be necessary to provide these in liquid form, through a tube.

These nutrients include carbohydrates, proteins, fats, vitamins, minerals and water; all essential to build body tissue and provide energy for bodily functions. Even an inability to fulfil your requirement for one of these has the ability to greatly affect your health.

You will be accessed to ensure that the type of tube feeding that is made available to you will be appropriate for you to maximise your nutritional intake. The diagram below illustrates how such decisions are made:

There are also different types of liquid feeds available, both for enteral and parenteral nutrition therapy and your dietitian will ensure that you receive the type specific to meet your requirements taking in to account all aspect of your medical history. 

As you are monitored there may be times where feeds are changed, it may be to introduce/reduce calories, add/remove individual components, or alter feeding times and volumes. These are all to ensure you retain a healthy nutritional balance.

There will be a number of people involved with your nutritional care. Many hospitals have a 'Nutrition Team' who have constituent members; Consultant, nutrition nurse specialist, dietitian and pharmacist. Additional members may be a biochemist, speech and language therapist or a psychologist. Where there is no nutrition team you will have nominated healthcare professionals who will manage your care. You should always find out who and how to contact your nominated healthcare professionals when you have issues/questions/concerns in relation to your home artificial nutrition.

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