ACBN Case Studies & Practical Application 3 — Questions and Answers
Question 1: A 45-year-old woman with PCOS and insulin resistance asks about dietary approaches to manage symptoms. Which dietary pattern has the strongest evidence for improving insulin sensitivity in PCOS?
- Very high-fat ketogenic diet only
- Low-glycemic index diet with moderate carbohydrate intake (Correct answer)
- Raw food diet
- High-protein diet exceeding 2.5 g/kg body weight
Correct answer: Low-glycemic index diet with moderate carbohydrate intake
Low-glycemic index diets reduce postprandial insulin spikes and have the strongest evidence base for improving insulin sensitivity and hormonal profiles in PCOS.
Question 2: A clinical nutritionist is counseling a client with stage 3 chronic kidney disease (GFR 35 mL/min). Which nutrient restriction is most critical to prevent disease progression?
- Vitamin C to <60 mg/day
- Dietary phosphorus to 800-1,000 mg/day (Correct answer)
- Total fat to <10% of calories
- Vitamin B6 to <1 mg/day
Correct answer: Dietary phosphorus to 800-1,000 mg/day
Phosphorus restriction is essential in CKD stage 3 to prevent hyperphosphatemia, secondary hyperparathyroidism, and accelerated renal deterioration.
Question 3: A 16-year-old female athlete presents with stress fractures, amenorrhea, and restrictive eating. Which condition best describes this clinical picture?
- Anorexia nervosa with secondary osteoporosis
- Relative Energy Deficiency in Sport (RED-S) (Correct answer)
- Exercise-induced anemia
- Hypothyroidism from overtraining
Correct answer: Relative Energy Deficiency in Sport (RED-S)
RED-S (formerly the Female Athlete Triad) encompasses low energy availability, menstrual dysfunction, and bone stress injuries resulting from inadequate fueling relative to exercise demands.
Question 4: A hospitalized patient post-major surgery has an albumin of 2.8 g/dL and prealbumin of 10 mg/dL. The team plans to initiate nutrition support. Which route is preferred if the GI tract is functional?
- Total parenteral nutrition (TPN) via central line
- Enteral nutrition via nasogastric tube (Correct answer)
- Peripheral parenteral nutrition (PPN) only
- Oral diet with protein supplements only
Correct answer: Enteral nutrition via nasogastric tube
Enteral nutrition is preferred over parenteral when the GI tract is functional because it maintains gut integrity, reduces infection risk, and is more cost-effective.
Question 5: A client reports taking 10,000 IU vitamin D daily for 6 months without physician supervision. Labs show calcium 11.2 mg/dL. Which condition do these findings suggest?
- Vitamin D deficiency masking
- Vitamin D toxicity causing hypercalcemia (Correct answer)
- Primary hyperparathyroidism unrelated to supplements
- Normal variation for vitamin D users
Correct answer: Vitamin D toxicity causing hypercalcemia
Chronic high-dose vitamin D supplementation causes hypercalcemia through increased intestinal calcium absorption and bone resorption, a classic sign of vitamin D toxicity.
Question 6: A nutrition counselor working with a client recovering from alcohol use disorder notes macrocytic anemia and peripheral neuropathy. Which nutritional deficiencies most likely explain both findings?
- Iron and vitamin C deficiency
- Folate and thiamine deficiency (Correct answer)
- Vitamin B12 and zinc deficiency
- Calcium and riboflavin deficiency
Correct answer: Folate and thiamine deficiency
Chronic alcohol use impairs folate absorption (causing macrocytic anemia) and depletes thiamine (causing peripheral and central neuropathy).
Question 7: A 60-year-old man with heart failure is placed on a 2,000 mg/day sodium restriction and experiences worsening fatigue and muscle cramps. His diuretic dose was recently increased. What should the nutritionist assess first?
- Protein intake adequacy
- Potassium and magnesium status (Correct answer)
- Total caloric intake
- Vitamin D levels
Correct answer: Potassium and magnesium status
Loop diuretics cause significant urinary potassium and magnesium losses; fatigue and muscle cramps are classic symptoms of hypokalemia and hypomagnesemia.
ACBN Case Studies & Practical Application 3
A 45-year-old woman with PCOS and insulin resistance asks about dietary approaches to manage symptoms.
Which dietary pattern has the strongest evidence for improving insulin sensitivity in PCOS?