Nutrition and Weight Management
Nutrition questions usually test energy balance and scope of practice rather than biochemistry.
Energy balance. Weight change tracks calories in versus out. A pound of fat stores roughly 3,500 kcal, so a 500 kcal daily deficit predicts about one pound per week. Treat that as a rule of thumb, not a law, because metabolic adaptation and water shifts flatten real curves. A sensible target is 0.5-1% of body weight lost per week.
Macronutrients. Protein and carbohydrate supply about 4 kcal per gram, fat about 9, and alcohol about 7. Protein needs rise with resistance training, commonly 1.4-2.0 g/kg for active clients versus 0.8 g/kg as a general minimum. Carbohydrate fuels high-intensity work; fat supports hormone function and should not be driven to zero.
Hydration and fiber. Roughly 2-3 L of fluid daily for most adults, more in heat and with heavy sweating; 25-35 g fiber. Electrolytes matter in long or hot sessions.
Traps: spot reduction is a myth because fat is lost systemically; toning means building muscle and losing fat, not converting one tissue into another; food diaries under-report intake; supplements are loosely regulated, so claims outrun evidence. Never prescribe diets or treat disease. Educate generally and refer to a registered dietitian.
Worked example: a 90 kg client wants fat loss. At 1.6 g/kg, protein is about 144 g per day, the deficit stays near 500 kcal, and progress is judged on a weekly average of scale weight plus waist circumference, not one morning weigh-in.