LICENSED DIETITIAN/NUTRITIONIST
(LDN) PRACTICE EXAM QUESTION AND
CORRECT ANSWERS (VERIFIED
ANSWERS) PLUS RATIONALES 2026 Q&A
INSTANT DOWNLOAD PDF
1. Which macronutrient provides the most calories per gram?
A. Carbohydrate
B. Protein
C. Fat
D. Alcohol
Answer: C
Rationale: Fat provides 9 kcal per gram, which is more than carbohydrates and
protein (4 kcal/g) and alcohol (7 kcal/g).
2. The primary function of dietary fiber is to:
A. Provide energy
B. Aid protein synthesis
C. Promote gastrointestinal health
D. Increase blood glucose
Answer: C
Rationale: Dietary fiber supports bowel regularity, gut health, and helps reduce
risk of chronic disease.
, 3. Which vitamin is essential for calcium absorption?
A. Vitamin A
B. Vitamin C
C. Vitamin D
D. Vitamin K
Answer: C
Rationale: Vitamin D enhances intestinal absorption of calcium and phosphorus.
4. A patient with phenylketonuria (PKU) must restrict intake of:
A. Tryptophan
B. Phenylalanine
C. Tyrosine
D. Methionine
Answer: B
Rationale: PKU is caused by inability to metabolize phenylalanine, leading to
toxic accumulation.
5. Which mineral is a component of hemoglobin?
A. Zinc
B. Calcium
C. Iron
D. Magnesium
Answer: C
Rationale: Iron is required for oxygen transport as part of hemoglobin.
6. The Acceptable Macronutrient Distribution Range (AMDR) for
carbohydrates in adults is:
A. 10–20%
B. 20–35%
, C. 45–65%
D. 65–80%
Answer: C
Rationale: Carbohydrates should provide 45–65% of total energy intake.
7. Which fat is most associated with increased LDL cholesterol?
A. Monounsaturated fat
B. Polyunsaturated fat
C. Trans fat
D. Omega-3 fat
Answer: C
Rationale: Trans fats raise LDL and lower HDL cholesterol, increasing
cardiovascular risk.
8. Basal metabolic rate (BMR) is defined as:
A. Energy used during exercise
B. Energy needed for digestion
C. Energy required to maintain vital functions at rest
D. Total daily energy expenditure
Answer: C
Rationale: BMR reflects energy needed for essential physiological functions at
rest.
9. Which nutrient deficiency causes scurvy?
A. Vitamin A
B. Vitamin C
C. Vitamin K
D. Vitamin E
(LDN) PRACTICE EXAM QUESTION AND
CORRECT ANSWERS (VERIFIED
ANSWERS) PLUS RATIONALES 2026 Q&A
INSTANT DOWNLOAD PDF
1. Which macronutrient provides the most calories per gram?
A. Carbohydrate
B. Protein
C. Fat
D. Alcohol
Answer: C
Rationale: Fat provides 9 kcal per gram, which is more than carbohydrates and
protein (4 kcal/g) and alcohol (7 kcal/g).
2. The primary function of dietary fiber is to:
A. Provide energy
B. Aid protein synthesis
C. Promote gastrointestinal health
D. Increase blood glucose
Answer: C
Rationale: Dietary fiber supports bowel regularity, gut health, and helps reduce
risk of chronic disease.
, 3. Which vitamin is essential for calcium absorption?
A. Vitamin A
B. Vitamin C
C. Vitamin D
D. Vitamin K
Answer: C
Rationale: Vitamin D enhances intestinal absorption of calcium and phosphorus.
4. A patient with phenylketonuria (PKU) must restrict intake of:
A. Tryptophan
B. Phenylalanine
C. Tyrosine
D. Methionine
Answer: B
Rationale: PKU is caused by inability to metabolize phenylalanine, leading to
toxic accumulation.
5. Which mineral is a component of hemoglobin?
A. Zinc
B. Calcium
C. Iron
D. Magnesium
Answer: C
Rationale: Iron is required for oxygen transport as part of hemoglobin.
6. The Acceptable Macronutrient Distribution Range (AMDR) for
carbohydrates in adults is:
A. 10–20%
B. 20–35%
, C. 45–65%
D. 65–80%
Answer: C
Rationale: Carbohydrates should provide 45–65% of total energy intake.
7. Which fat is most associated with increased LDL cholesterol?
A. Monounsaturated fat
B. Polyunsaturated fat
C. Trans fat
D. Omega-3 fat
Answer: C
Rationale: Trans fats raise LDL and lower HDL cholesterol, increasing
cardiovascular risk.
8. Basal metabolic rate (BMR) is defined as:
A. Energy used during exercise
B. Energy needed for digestion
C. Energy required to maintain vital functions at rest
D. Total daily energy expenditure
Answer: C
Rationale: BMR reflects energy needed for essential physiological functions at
rest.
9. Which nutrient deficiency causes scurvy?
A. Vitamin A
B. Vitamin C
C. Vitamin K
D. Vitamin E
