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Tackling undernutrition in the community

Luci Daniels
SRD BSc(Nutr)
State Registered Dietitian

Health professionals are increasingly aware of the risks to their patients from undernutrition. It can affect both morbidity and mortality and is often underestimated and unrecognised. The true prevalence in the community is not known, but studies show an incidence of around 10-20% in certain patient groups.(1,2) It is estimated that between 13% and 40% of people admitted to hospital are at least mildly malnourished,(3) a problem that could have been dealt with earlier in the community. Undernutrition does not just happen to older patients in hospital, it can happen to all sorts of people, from across the age ranges and with a wide variety of health problems.
The focus on "healthy eating" to prevent conditions such as obesity, coronary heart disease and certain cancers hides the needs of certain patient groups to receive advice on how to increase their dietary intake. Many patients in fact welcome weight loss initially, especially those who were previously overweight. It becomes a real cause of concern when they cannot stop losing weight and then are unsure about what they should be eating to stop the downward weight trend. Such patients' poor dietary intake is often masked by a seemingly "adequate" body mass index (BMI), weight for height. Nutrition assessment tools should not rely solely on BMI data to identify those "at risk" of undernutrition, but should also consider recent unintentional weight loss and dietary intake.(4)

Undernutrition - criteria to identify who is at risk

  • People with a low body weight, especially if BMI
  • Recent unintentional weight loss.
  • Reduced food intake, loss of appetite, loss of interest in food/meals.

It is important to consider offering nutrition advice to patients with any or all of the above criteria.
The hazards of undernutrition
Undernutrition results from an inadequate dietary energy intake. A low energy intake often correlates with a reduced intake of essential nutrients, including protein, vitamins and minerals. The consequences are not simply due to tissue loss but can result from physiological, metabolic and functional effects.(5)
The hazards of undernutrition include:

  • Prolonged recovery from illness.
  • Impaired immune response leading to a predisposition to infection.
  • Delayed wound healing.
  • Muscle wasting and weakness that can affect mobility, cardiac function and respiratory function.
  • Increased risk of pressure sores.
  • Increased tiredness, as well as a lack of concentration and apathy.
  • Depression, self-neglect and reduced social interactions.

At-risk groups
Undernutrition can occur in a variety of patient groups, such as pre- and postsurgery, oncology patients undergoing chemotherapy or radiotherapy, HIV patients, the elderly (especially if recently bereaved), those with mental health problems, and those with a chronic condition, as well as during and following a prolonged illness or infection.
It can also occur in "well people" who just can't find the time to eat a full and balanced diet. Busy lifestyles often mean that meals and food become a low priority, and it is often at these times when good nourishment is really important. Intensive athletic training programmes, heavy work schedules and periods of intense study can lead to a reduced food intake. Many people are simply "naturally underweight" and have low reserves to call upon if they become unwell. An improved nutritional intake will benefit all these situations before nutrition-related consequences set in.
Practical and realistic solutions are essential if we are to reduce the risks of undernutrition. The relatives and families of people at risk of undernutrition find talking about food and mealtimes very stressful. It is so important to tackle the issue in a sensitive way as early as possible.
There is good evidence that early nutrition support improves outcome. This evidence comes mainly from studies looking at the benefits of nutrition support in hospitalised patients, especially pre- and postsurgery. It has been estimated that up to one-third of oncology patients die from cancer cachexia rather than the disease itself. Nutrition support can be looked at as a continuum, from an increased intake of ordinary food, to ordinary food with additional vitamin- and mineral-fortified dietary supplements, to enteral tube feeds and, as a last resort, parenteral nutrition. There is an understanding to feed enterally whenever possible.(6)

Conceptions of a "good diet"
Those at risk of undernutrition often self-select low- energy diets. They have a poor appetite, find large meals offputting and tend to fill up on "clear fluids". Advice needs to be clear, simple and consistent, along the line of the "Tips for good nutrition" (see box).

Dietary supplements
Vitamin- and mineral-fortified dietary supplements are widely used in both hospitals and the community when food intake is reduced. It is now widely accepted that we should give advice to people with a poor food intake sooner rather than later, before nutrition-related consequences set in. That often means advising on the use of dietary supplements, as well as "solid food" for those having problems eating a full and balanced diet.
Choose a well-formulated dietary supplement containing a mix of protein, fat and carbohydrate to provide energy, as well as a range of vitamins and minerals to make up for the lack of these nutrients in the diet. As a guide, choose supplements containing around 50% of the RDA of a range of vitamins and minerals and 250-300 calories per serving, so that a daily intake of two such supplements will provide 100% of the RDA of these vital nutrients and over 500 calories.
A range of dietary supplements are available at the local pharmacy as well as on prescription.


  1. Edington J, Kon P, Martyn CN. Prevalence of malnutrition in patients in general practice. Clin Nutr 1996;15:60-3.
  2. Finch SA, Doyle W, Lowe C, et al. National diet and nutrition survey: people aged 65 years and over. London: HMSO; 1998.
  3. Malnutrition Advisory Group. Guidelines for the detection and management of malnutrition. London: BAPEN; 2000.
  4. McWhirter JR, Pennington CR. Incidence and recognition of malnutrition in hospital. BMJ 1994;308:945-8.
  5. Royal College Physicians. Nutrition and patients, a doctor's responsibility. London: RCP; 2002.
  6. Thomas B. Manual of dietetic practice. London: BDA; 2001.

British Dietetic Association