GLOSSARY

Cachexia is a disease-associated wasting syndrome involving altered metabolism and tissue loss, not merely ordinary dieting.

Cachexia is a disease-associated wasting syndrome that cannot be understood as ordinary voluntary dieting alone. Sarcopenia concerns muscle strength and quantity or quality within a defined diagnostic framework, while frailty describes broader vulnerability. These conditions can overlap without being identical. Nutrition support may be necessary but may not reverse every disease-driven process by itself. Assess function, underlying disease, inflammation and treatment goals, and avoid assuming that a protein powder alone can resolve progressive wasting or frailty.

Malnutrition can occur across body sizes, including in a person with obesity. Assessment considers reduced intake or assimilation, disease-related inflammation, weight trajectory and relevant body-composition or functional findings. Undernutrition, overnutrition and individual micronutrient deficiencies describe overlapping but distinct problems. A stable or high body weight cannot exclude inadequate nutrient supply or muscle loss. In an athlete, declining intake, recurrent illness or unintentional weight loss deserves assessment rather than automatic praise for becoming lighter.

Protein targets depend on body size, training, energy intake, age and clinical status. A high-protein label does not identify the actual amount, amino-acid quality or distribution. During weight reduction, adequate protein and resistance exercise can help preserve lean tissue, but neither removes the consequences of an excessive energy deficit. Kidney disease can require a different clinical approach. Do not transfer a healthy athlete's protein strategy directly to a person with impaired renal function.