RDN Lifecycle Nutrition 3 — Questions and Answers
Question 1: Which nutrient supplementation during the periconceptional period (one month before through first trimester) most effectively reduces the risk of neural tube defects?
- Iron 27 mg/day
- Folic acid 400–800 mcg/day (Correct answer)
- Vitamin A 5000 IU/day
- Calcium 1000 mg/day
Correct answer: Folic acid 400–800 mcg/day
Folic acid 400–800 mcg/day taken before conception and through the first trimester significantly reduces the incidence of neural tube defects such as spina bifida.
Question 2: A postmenopausal woman's DEXA scan shows a T-score of −2.7. What is her diagnosis, and what calcium intake does she need daily?
- Osteopenia; 1000 mg/day
- Osteoporosis; 1200 mg/day (Correct answer)
- Osteoporosis; 1000 mg/day
- Osteopenia; 1200 mg/day
Correct answer: Osteoporosis; 1200 mg/day
A T-score of −2.5 or below defines osteoporosis, and postmenopausal women require 1200 mg/day of calcium to support bone health.
Question 3: Which of the following is the most appropriate complementary food to introduce first to a 6-month-old exclusively breastfed infant?
- Whole cow's milk
- Iron-fortified single-grain cereal or pureed meat (Correct answer)
- Honey-sweetened yogurt
- Fruit juice
Correct answer: Iron-fortified single-grain cereal or pureed meat
Iron-fortified cereals or pureed meats are recommended as first complementary foods to address the iron gap in exclusively breastfed infants at 6 months.
Question 4: An older adult (age 72) with limited sun exposure is assessed for nutritional risk. What is the current RDA for vitamin D for this individual?
- 400 IU (10 mcg)/day
- 600 IU (15 mcg)/day
- 800 IU (20 mcg)/day (Correct answer)
- 1000 IU (25 mcg)/day
Correct answer: 800 IU (20 mcg)/day
Adults aged 71 and older have an RDA of 800 IU (20 mcg)/day for vitamin D, reflecting reduced cutaneous synthesis and higher risk of deficiency.
Question 5: A school-age child is diagnosed with iron-deficiency anemia. Which dietary strategy most effectively enhances non-heme iron absorption?
- Pairing iron-rich foods with calcium-rich foods
- Consuming iron-rich foods with vitamin C sources (Correct answer)
- Taking iron supplements with tea or coffee
- Eating iron-rich foods with phytate-containing whole grains
Correct answer: Consuming iron-rich foods with vitamin C sources
Vitamin C (ascorbic acid) converts ferric iron to the more absorbable ferrous form and chelates iron, significantly enhancing non-heme iron absorption.
Question 6: Which protein intake recommendation is MOST appropriate for a healthy 70-year-old to preserve lean muscle mass?
- 0.8 g/kg body weight/day (standard adult RDA)
- 1.0–1.2 g/kg body weight/day (Correct answer)
- 1.5–2.0 g/kg body weight/day
- 0.6 g/kg body weight/day
Correct answer: 1.0–1.2 g/kg body weight/day
Current evidence supports 1.0–1.2 g/kg/day for healthy older adults to counteract anabolic resistance and preserve skeletal muscle mass (sarcopenia prevention).
Question 7: Gestational diabetes is first diagnosed during pregnancy. Which macronutrient distribution strategy is the primary dietary intervention?
- Very low fat (<20% of calories) with high carbohydrate intake
- Controlled carbohydrate intake (40–45% of calories) distributed across 3 meals and 2–3 snacks (Correct answer)
- High protein (>30% of calories) with minimal carbohydrates (<10%)
- Standard MyPlate distribution with no modifications
Correct answer: Controlled carbohydrate intake (40–45% of calories) distributed across 3 meals and 2–3 snacks
Carbohydrate-controlled diets distributing 40–45% of calories across multiple small meals and snacks are the cornerstone of gestational diabetes medical nutrition therapy.
RDN Lifecycle Nutrition 3
Which nutrient supplementation during the periconceptional period (one month before through first trimester) most effectively reduces the risk of neural tube defects?