Final answer:
Malnutrition encompasses both undernutrition, including protein-calorie malnutrition, and overnutrition, which can lead to obesity.
Primary PCM is due to insufficient protein and calorie intake, whereas secondary PCM stems from other medical conditions.
Obesity, generally caused by an energy balance issue, can also be secondary to medical or lifestyle factors.
Step-by-step explanation:
Malnutrition and Nutrition Imbalances
Malnutrition includes both undernutrition and overnutrition, either of which can lead to health issues. Protein-calorie malnutrition (PCM) or protein-energy malnutrition refers to a dietary deficiency where there's an insufficient supply of dietary proteins and calories, impeding cell growth and maintenance.
There are two types of PCM: Primary PCM is directly caused by insufficient dietary intake of proteins and calories, while Secondary PCM results from an underlying disease or condition that affects nutrient absorption or usage.
Specific nutrient imbalances occur when too much or not enough of a particular nutrient is present in the diet, leading to health problems such as vitamin deficiencies or toxicities, while nutrient density refers to the amount of nutrients a food provides relative to its energy content.
Obesity is a form of overnutrition and is primarily due to a chronic imbalance between energy intake and energy expenditure. Secondary obesity can result from various medical conditions, medications, or lifestyle factors that alter the body's energy balance or how fat is stored.