TheoryRegistered Dietitian Practice Questions
Free Registered Dietitian practice questions with answers and plain-English explanations. Browse the PDF, video and online mock test.
Registered Dietitian Questions
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Q1Which anthropometric measurement is most commonly used to assess body fat distribution and cardiovascular disease risk?
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✓ Correct answer: Waist circumference
Waist circumference reflects visceral adiposity and is the most widely used anthropometric marker for cardiovascular and metabolic disease risk. BMI reflects total weight relative to height but does not distinguish fat distribution.
Q2Which laboratory value is considered the best single marker of long-term glycemic control in patients with diabetes?
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✓ Correct answer: Glycated hemoglobin (HbA1c)
HbA1c reflects average blood glucose over approximately 2–3 months and is the gold standard for monitoring long-term glycemic control. Fasting glucose and postprandial glucose are point-in-time measurements.
Q3The Subjective Global Assessment (SGA) classifies nutritional status into which categories?
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✓ Correct answer: Well-nourished, Moderately malnourished, Severely malnourished
SGA uses clinical judgment incorporating history and physical findings to classify patients as A (well-nourished), B (moderately malnourished), or C (severely malnourished). It does not use a four-tier system.
Q4A hospitalized patient has a serum albumin of 2.8 g/dL. Which factor most limits the interpretation of albumin as a nutritional marker in this patient?
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✓ Correct answer: Acute-phase response reduces albumin synthesis and increases its redistribution
Albumin is a negative acute-phase protein; inflammation, stress, and illness suppress its synthesis and cause fluid shifts that lower serum levels independently of nutritional intake. Its 20-day half-life makes it a poor marker of short-term nutrition changes as well.
Q5According to the 2012 ASPEN/AND consensus definitions, which combination of criteria is required to diagnose malnutrition in adults in the context of chronic illness?
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✓ Correct answer: Inadequate energy intake AND one of: weight loss, loss of muscle mass, loss of subcutaneous fat, localized fluid accumulation, or reduced grip strength
The 2012 ASPEN/AND consensus framework requires inadequate energy intake plus at least one of five physical findings: weight loss, loss of muscle, loss of subcutaneous fat, fluid accumulation, or diminished functional status. Lab values alone do not diagnose malnutrition under this framework.
Q6Which equation is most commonly used in clinical practice to estimate resting metabolic rate (RMR) in adults?
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✓ Correct answer: Mifflin-St Jeor equation
The Mifflin-St Jeor equation has been validated as the most accurate predictive equation for RMR in normal-weight and obese adults. Harris-Benedict was historically dominant but overestimates RMR in obese individuals.
Q7A 70 kg critically ill patient is mechanically ventilated. Which method provides the most accurate measurement of energy expenditure in this patient?
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✓ Correct answer: Indirect calorimetry
Indirect calorimetry directly measures oxygen consumption and carbon dioxide production to calculate energy expenditure and is the gold standard for critically ill patients, in whom predictive equations are especially inaccurate.
Q8A non-obese critically ill patient (BMI 24, weight 75 kg) is in the acute phase of illness. What initial energy target do current ASPEN/SCCM guidelines recommend?
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✓ Correct answer: Approximately 25–30 kcal/kg/day advancing to goal over 24–48 hours
ASPEN/SCCM guidelines for non-obese critically ill adults recommend advancing to 25–30 kcal/kg/day (actual body weight) over the first 24–48 hours. Starting at full repletion immediately is not recommended due to refeeding and tolerance concerns.
Q9What is the recommended protein intake (g/kg/day actual body weight) for a critically ill adult without renal or hepatic failure?
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✓ Correct answer: 1.2–2.0 g/kg/day
Current ASPEN/SCCM guidelines recommend 1.2–2.0 g/kg/day of protein for most critically ill patients to attenuate lean body mass loss and support recovery. The RDA of 0.8 g/kg is for healthy adults and is insufficient in critical illness.
Q10For a morbidly obese patient (BMI > 40) requiring EN support in the ICU, ASPEN recommends estimating protein needs based on which weight?
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✓ Correct answer: Ideal body weight, targeting 2.0–2.5 g/kg IBW/day
ASPEN recommends using ideal body weight for protein calculations in morbidly obese ICU patients, targeting 2.0–2.5 g/kg IBW/day to preserve lean mass during hypocaloric feeding. Actual body weight overestimates needs due to excess adipose tissue.
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