A quarter of all adults admitted to hospital and care homes in the UK are at risk of malnutrition, a major survey has found.
Malnutrition can mean a longer hospital stay
The British Association for Parenteral and Enteral Nutrition (Bapen) collected data on 11,665 new admissions to 372 institutions over three days.
The association is calling for nutrition screening on admission as standard for all patients.
Ministers said an action plan had been launched to improve services.
HOSPITAL PATIENTS' RISK
Under 20 years old: 30%
Over 90: 38%
The Bapen survey found that it was not just older patients who were at risk of malnutrition.
Patients under the age of 30 had a 27% risk of malnutrition, compared with a 34% for those over 80.
Malnourished people stay in hospital longer, succumb to infection more often and visit their GP more frequently.
They also require longer-term care and more intensive nursing care.
However, the symptoms may not be immediately obvious.
Professor Marinos Elia, Bapen chair, said: "This finding establishes - if there was any doubt - that malnutrition is a major public health issue in the community that must be addressed both at source and when individuals are admitted into care.
"All hospitals and care homes should implement nutrition screening on admission to ensure that all those at risk - no matter their age or physical appearance - are identified and an appropriate and individual nutritional care plan is provided."
Impaired immune responses
Reduced muscle strength and fatigue
Increased difficulties in breathing
Impaired wound healing
Apathy, depression and self-neglect
In 2004, the Department of Health issued core standards for the NHS which commit trusts to providing patients with a balanced and nutritional diet.
Two years later, the National Institute for Clinical Excellence issued guidelines recommending that all new patients be routinely screened on admission and offered specialist nutritional support if necessary.
But charities such as Age Concern complain malnutrition remains prevalent because policy is not necessarily being put into practice.
Nurses, it is often argued, simply do not have the time to ensure patients are eating properly.
The problem is an expensive one, thought to cost the NHS more than £7bn every year.
The Bapen survey found that 89% of hospitals and 82% of care homes who took already have screening policies in place.
Ivan Lewis, Care Services Minister, said the government had launched a nutrition action plan to improve monitoring and care of patients.
He said: "We know that good nutrition is central to people's good health and ability to recover from illness.
"It is important that every older person is given a nutritional screening which is reviewed on a regular basis."