Diagnosing malnutrition

Several factors are taken into account to check whether someone is malnourished or at a high risk of malnutrition. In adults, these include: body mass index (BMI)   a measure that can be used to determine if you're a healthy weight for your height whether you've unintentionally lost weight in recent months whether an illness means you're unable to feed yourself or absorb nutrients from your diet You would normally be considered malnourished if you have a BMI of less than 18.5 or you've unintentionally lost more than 5% of your body weight during the last three to six months. However, in some cases, doctors may be concerned about malnutrition if you have a BMI between 18.5 and 20. You may be considered at a high risk of malnutrition if: an illness means you have eaten nothing for the last five days, or you're likely to eat nothing for the next five days you don't absorb nutrients from food well for example, you have a condition, such as  Crohn's disease , that causes the digestive system to become inflamed there's an underlying reason why your body is likely to use up nutrients at a higher rate or have an increased need for nutrients you have difficulty eating and drinking A vitamin or mineral deficiency can usually be diagnosed with a blood test . Diagnosing malnutrition in children Diagnosing malnutrition in children involves taking a measurement of their weight and height and comparing it against the expected average height and weight for a child of that age. Some children will be below average because they're naturally smaller, but a significant drop below the expected level could indicate a risk of malnutrition. Blood tests can also be used to measure protein levels in the blood. Low levels of protein may suggest that a child is malnourished.