RD Exam Plan

Principles of Dietetics: practice questions

4 original questions · 4 editor-approved · every choice explained.

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Blueprint-mapped questions with full rationales for every choice.

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Principles of DieteticsDifficulty 3/5

Which reference value should be used to assess whether an individual's usual nutrient intake is likely adequate?

  1. AThe Estimated Average Requirement, because it allows a probability assessment
  2. BThe Tolerable Upper Intake Level, because it defines the safe ceiling
  3. CThe Adequate Intake, because it is set from observed intakes in healthy groups
  4. DThe Recommended Dietary Allowance, because it covers nearly all healthy people
Show answer and rationale

Correct: A. The EAR is the reference used to assess the adequacy of an individual's usual intake, because it supports a probability statement about meeting requirements. The RDA is a planning goal, the UL is a safety ceiling and the AI is used where an EAR could not be established.

  • D — The RDA is used to plan intakes, not to judge adequacy of an individual's intake.
  • B — The UL addresses risk of excess rather than adequacy.
  • C — The AI is used only when the evidence is insufficient to set an EAR.
Principles of DieteticsDifficulty 3/5

A cohort study reports a strong association between a dietary pattern and lower disease risk. What is the appropriate conclusion?

  1. AThe dietary pattern causes the reduction in disease risk in this population
  2. BAn association exists that may be confounded and needs further evidence
  3. CThe finding is invalid because cohort studies cannot show relationships
  4. DThe pattern should be recommended to all clients with that condition
Show answer and rationale

Correct: B. Observational designs can establish association but not causation, because unmeasured confounding and reverse causation remain possible. Strength of association does not convert a cohort finding into a causal claim.

  • A — Causation requires designs that control allocation, not observation alone.
  • C — Cohort studies are valid for association and hypothesis generation.
  • D — Population-level recommendations need a stronger evidence base.
Principles of DieteticsDifficulty 2/5

A client says they know they should cut sodium but cannot see how to do it with their family's cooking. Which counselling approach fits best?

  1. ASet a specific sodium target and ask the client to record all intake
  2. BProvide a printed low-sodium food list and schedule a follow-up visit
  3. CExplore the barrier and elicit the client's own ideas before advising
  4. DExplain the pathophysiology of sodium and blood pressure in detail
Show answer and rationale

Correct: C. The client has knowledge but faces a practical and social barrier. Motivational interviewing directs you to explore ambivalence and evoke the client's own solutions before offering advice.

  • B — A handout adds information the client already has.
  • D — More pathophysiology does not address a practical barrier.
  • A — A target without a feasible method is unlikely to be met.
Principles of DieteticsDifficulty 2/5

Which factor most increases non-heme iron absorption when eaten at the same meal?

  1. ATannins from black tea taken immediately after the meal
  2. BPhytates from whole grains and legumes present in the dish
  3. CAscorbic acid from a citrus fruit or juice served with the meal
  4. DCalcium from a glass of milk consumed alongside the meal
Show answer and rationale

Correct: C. Vitamin C reduces ferric to ferrous iron and forms a soluble complex, substantially improving non-heme absorption. Calcium, tannins and phytates all inhibit it.

  • D — Calcium competes with iron and reduces absorption.
  • A — Tannins bind iron and inhibit absorption.
  • B — Phytates chelate iron and reduce bioavailability.

Primary references

  1. Registered Dietitian Examination Test Specifications, January 1 2022 – December 31 2026 — Commission on Dietetic Registration (CDR) · primary · retrieved 2026-09-22, verified 2026-09-22