You can become malnourished due to a consequence of primary or secondary malnutrition, or both. Primary malnutrition occurs when you don’t take in enough energy, often in relation to food insecurity or when adequate food, whether that’s total calories or specific micronutrients, is not available. Primary malnutrition can also happen if you have a poor appetite due to illness or a weight-related eating disorder such as anorexia nervosa.
Secondary malnutrition occurs when your body doesn’t adequately absorb energy, due to infectious conditions such as diarrhoea, measles or parasitic infections, or medical or surgical problems that affect your digestive system. There are also increased metabolic demands on your body after an illness or surgery, and this is another cause of secondary malnutrition.
Malnutrition is both a cause and consequence of ill health, as it makes you more susceptible to disease and infection due to your impaired immune function. You might find that you consult health practitioners more frequently and take longer to recover from episodes of illness or injuries. It’s estimated that 5% of people in England are malnourished, though this is more prevalent in specific sub groups. The elderly are particularly at risk to malnutrition and some micro-nutrient deficiencies in this country, as, for example, 35% of elderly individuals in aged care homes are deficient in folate and 40% are deficient in vitamin C.
You are more likely to be malnourished if you are from a low socio-economic background, have a history of or recent infectious and parasitic disease or recent surgery, are on certain medications, or have a chronic disease. For children, a low birth weight, an adolescent mother, and not being breastfed can lead to malnutrition, whilst adults specifically can be susceptible if they are older, unable to prepare food, pregnant or lactating, or abuse alcohol or drugs. Consult your doctor for more information.