Clinical Nutritionist CCN Trivia 5 — Questions and Answers
Question 1: Which carotenoid found in tomatoes and watermelon is associated with reduced risk of prostate cancer in epidemiological studies?
- Beta-carotene
- Lutein
- Zeaxanthin
- Lycopene (Correct answer)
Correct answer: Lycopene
Lycopene is a red carotenoid with potent antioxidant activity; observational studies link higher lycopene intake with lower prostate cancer risk.
Question 2: Which type of dietary fiber, found in oats and barley, has strong evidence for lowering LDL cholesterol?
- Insoluble cellulose
- Resistant starch
- Beta-glucan (Correct answer)
- Pectin
Correct answer: Beta-glucan
Beta-glucan forms a viscous gel in the gut that binds bile acids, increasing their fecal excretion and forcing the liver to convert more cholesterol into new bile.
Question 3: In the context of protein quality, which scoring method endorsed by the FAO/WHO accounts for both amino acid content and digestibility?
- Biological Value (BV)
- Net Protein Utilization (NPU)
- Protein Digestibility-Corrected Amino Acid Score (PDCAAS) (Correct answer)
- Chemical Score
Correct answer: Protein Digestibility-Corrected Amino Acid Score (PDCAAS)
PDCAAS multiplies a food's amino acid score (relative to human needs) by its true fecal digestibility, yielding a score capped at 1.0.
Question 4: A CCN client reports numbness and tingling in hands and feet after months of high-dose supplementation with which B vitamin?
- Thiamine (B1)
- Riboflavin (B2)
- Pyridoxine (B6) (Correct answer)
- Cyanocobalamin (B12)
Correct answer: Pyridoxine (B6)
Chronic high-dose vitamin B6 supplementation (>100–200 mg/day) can cause sensory peripheral neuropathy that is reversible upon discontinuation.
Question 5: Which organ secretes the hormone insulin in response to elevated blood glucose levels?
- Adrenal cortex
- Liver
- Pancreatic beta cells (Correct answer)
- Thyroid gland
Correct answer: Pancreatic beta cells
Insulin is synthesized and secreted by the beta cells of the islets of Langerhans in the pancreas in response to postprandial hyperglycemia.
Question 6: The 'thermic effect of food' (TEF) is highest for which macronutrient, consuming approximately 20–30% of its calories during digestion?
- Carbohydrate
- Fat
- Protein (Correct answer)
- Alcohol
Correct answer: Protein
Protein has a TEF of 20–30%, far exceeding carbohydrate (5–10%) and fat (0–3%), partly due to the energy cost of urea synthesis and gluconeogenesis.
Question 7: Which essential trace mineral is a structural component of the antioxidant enzyme glutathione peroxidase?
- Zinc
- Copper
- Manganese
- Selenium (Correct answer)
Correct answer: Selenium
Selenium is incorporated as selenocysteine into glutathione peroxidase, enabling it to reduce hydrogen peroxide and lipid hydroperoxides.
Clinical Nutritionist CCN Trivia 5
Which carotenoid found in tomatoes and watermelon is associated with reduced risk of prostate cancer in epidemiological studies?