Last Updated on October 28, 2023
Malnutrition refers to both undernutrition (subnutrition) and overnutrition.
Undernutrition exists when the diet of an individual does not provide them with adequate calories and protein for maintenance and growth, or they cannot fully utilize the food they eat due to illness.
Overnutrition is a type of malnutrition a person consumes excessive calories. Overnutrition leads to problems of over-weight and obesity.
Having made the difference clear, it may be emphasized that the term malnutrition is used often for undernutrition and in this article too, the term has been used to convey undernutrition.
Risks for Malnutrition
- Elderly people, especially those who are hospitalized or in long-term institutional care
- Socially isolated people
- People on low incomes
- People with chronic eating disorders, such as bulimia or anorexia nervosa
- People convalescing after a serious illness or condition.
- Women gender in some societies
Causes of Malnutrition
- Poor diet
- Mental health problems
- Mobility/movement problems
- Digestive disorders and stomach conditions
- Ulcerative colitis
- Coeliac diease
- Crohn’s disease
- Alcoholism
- Food shortages
- Lack of breastfeeding in infants and children.
Signs and symptoms of malnutrition
- Loss of fat (adipose tissue)
- Stunted growth and Wasting
- Increased risk of infection
- Breathing difficulties, a higher risk of respiratory failure
- Depression
- Abnormally low body temperature
- Leucopenia
- Higher susceptibility to feeling cold
- Impaired healing process
- Lower sex drive
- Problems with fertility
- Reduced tissue mass
- Tiredness, fatigue, or apathy
- Irritability
- Deficiency-related diseases (such as scurvy and rickets).
In more severe cases the skin may become thin, dry, inelastic, pale, and cold. The fat in the face is lost, the cheeks look hollow and the eyes sunken. The hair becomes dry and sparse, falling out easily.
If calorie deficiency continues for long enough, there may be heart, liver and respiratory failure
Diagnosis of malnutrition
Prompt diagnosis is key to preventing complications. There are several ways of identifying adults who are malnourished, at risk of malnutrition, or obese.
- BMI [clinical impression of thin, acceptable weight, overweight.
- Cothes and/or jewelry have become loose fitting (weight loss).
- History of decreased food intake/ reduced appetite
- Acute disease effect – no nutritional intake or likelihood of no intake for more than 5 days.
British Association for Parenteral and Enteral Nutrition’ (Malnutrition Universal Screening Tool or MUST)
MUST has been designed to identify malnourished adults, especially elderly people. It is a five-step tool for use in hospitals, community and other care settings.
Must has 5 step plan
MUST is only used for identifying malnutrition or risk of malnutrition in adults. It is not designed to identify deficiencies/excesses in vitamin and/or mineral intake.
STEP 1 – BMI kg/m2 Score
Measure height and weight to get a BMI (body mass index) score.
- BMI >20 (>30 obese), score 0
- BMI 18.5 to 20 – score 1
- BMI <18.5 – score 2
If there are problems measuring BMI:
If height cannot be measured – use recently documented or self-reported height (if reliable and realistic). If the subject does not know or is unable to report their height, use one of the alternative measurements to estimate height (ulna, knee height or demispan).
If height and weight cannot be obtained – use mid upper arm circumference (MUAC) measurement to estimate BMI category.
STEP 2 – Weight Loss Score
Note percentage unplanned weight loss and score.
Unplanned weight loss in past 6 months
- <5% – score 0
- 5% to 10% – score 1
- 10% – score 2
If recent weight loss cannot be calculated, use self-reported weight loss (if reliable and realistic).
STEP 3 – Acute Disease Effect Score
-Establish acute disease (any underlying illness, such as a psychological condition) effect and score.
If the patient is acutely ill and there has been or is likely to be no nutritional intake for over 5 days – score 3.
STEP 4 – Overall Risk of Malnutrition
Add scores from steps 1, 2 and 3 together to obtain overall risk of malnutrition
STEP 1 + STEP 2 + STEP 3 = STEP 4
Add Scores together to calculate overall risk of malnutrition
- Low Risk – Score 0
- Medium Risk – Score 1
- High Risk – Score 2 or more
STEP 5 – Management
Use management guidelines and/or local policy to develop care plan.
- Low risk, score 0 – repetitive Screening
- Medium risk, score 1 – Observe
- High risk, score 2 or more – Treat
Treat underlying condition and provide help and advice on food choices, eating and drinking when necessary across all the categories
Record malnutrition risk category.
Record need for special diets and follow local policy.
Treatments for Malnutrition
The type of malnutrition treatment recommended depends mainly on its severity, and whether the patient has an underlying condition/illness which is a contributory factor. If so, that underlying illness/condition needs to be treated or addressed.
They state that the needs and preferences of the patient need to be taken into account. The patient, along with healthcare professionals, should be able to make informed decisions about care and treatment.
Aims for treatment are different in different people.
The main approach follows following
Typically, treatment will include a feeding program with a specially planned diet, and possibly some additional nutritional supplements.
Severely malnourished patients, or individuals who cannot get sufficient nutrition by eating or drinking may need and should receive artificial nutritional support.
The patient will be closely monitored for progress. Their treatment will be regularly reviewed to make sure their nutritional needs are being met.
Management include the treatment for any underlying conditions/illnesses which are contributory factors to the malnutrition.
Artificial nutritional support
There are two main types of artificial nutritional support, mainly for patients with severe malnutrition:
- Enteral nutrition or tube feeding where a tube is passed to the stomach through nostril [nasogastric tube].
- In some cases the tube is passed to the stomach through the skin on the abdomen, it is called gastrostomy or percutaneous endoscopic gastrostomy (PEG) tube.
- If it goes to the small intestine is called a jejunostomy or percutaneous endoscopic jejunostomy (PEJ) tube.
- Parenteral feeding – a sterile liquid is fed directly into the bloodstream (intravenously). Some patients may not be able to take nourishment directly into their stomach or small intestine.
The patient will be regularly monitored to check that he/she is receiving the right amount of calories and nutritional needs.
Malnutrition in Children
Malnutrition in children affects their growth and behavior and may have long-term effects in children.
The malnutrition in children are either due to protein deficiency or deficiency of particular vitamin or micronutrient.
Common manifestations of protein energy malnutrition are Kwashiorkor and marasmus. Scurvy [vitamin C deficiency], rickets [vitamin D deficiency], night blindness [vitamin A deficiency] and Beri beri [vitamin B1 deficiency] and anemia [iron, vitamin B12 ] are common malnutritions of childhood.
These have been discussed separately.