Final answer:
A low Body Mass Index (BMI) supports a medical diagnosis of malnutrition, with an adult BMI of 17 kg/m2 indicating undernutrition. BMI is a simple metric used to indicate body fat reserves, but it must be interpreted with caution as it does not distinguish between muscle and fat.
Step-by-step explanation:
The medical diagnosis of malnutrition can be supported by a low Body Mass Index (BMI). Specifically, an adult with a BMI of 17 kg/m2 is considered underweight as the normal BMI range for an adult is from 18 to 24.9 kg/m2. A BMI under 18.5 kg/m2 indicates that the individual has insufficient body fat reserves, which is a common sign of undernutrition. This low BMI could reflect a deficiency in energy-providing nutrients including carbohydrates, proteins, and fats, which are essential for maintaining body weight and energy.
It's important to note that BMI is a simple and useful tool for population studies, but its accuracy as an assessment tool for individuals can be limited, as it does not differentiate between muscle and fat mass. An athlete with substantial muscle mass, for example, might have a high BMI yet not be overweight or undernourished. Therefore, assessing BMI must be considered alongside other indicators of health and nutritional status.