Nutrition practice questions for the lifestyle medicine boards

Answer: E. Introduce complementary foods at 6 months while continuing to breastfeed

A (incorrect): WHO recommends introducing complementary foods at 6 months (180 days); normal growth so far does not justify a 12-month delay. B (incorrect): WHO calls for a diverse diet including daily animal-source foods and fruits and vegetables, and advises minimizing reliance on starchy staples. C (incorrect): WHO recommends continuing breastfeeding up to 2 years or beyond. D (incorrect): WHO advises limiting 100% fruit juice; it is not an appropriate first food. E (correct): WHO Recommendation 3 is introduction of complementary foods at 6 months while continuing to breastfeed (strong recommendation).

Source: WHO. WHO Guideline for complementary feeding of infants and young children 6-23 months of age. Geneva: WHO; 2023. ISBN 9789240081864. https://iris.who.int/handle/10665/373358 Locator: Executive summary, Recommendations 1, 3, 4 and 5, pp. x to xii.

Answer: D. FFQs underreported energy more, yet percent energy from protein was little biased

A (incorrect): Both instruments underreported energy. Men underreported by 12 to 14% on 24-hour recalls and 31 to 36% on FFQs; women by 16 to 20% and 34 to 38%. B (incorrect): The reverse is true; FFQ underreporting was roughly two to three times larger than 24-hour recall underreporting. C (incorrect): Protein intake was also underreported compared with the urinary nitrogen biomarker, by about 11 to 15% on recalls and 27 to 34% on FFQs. D (correct): Underreporting of energy and protein was much larger on FFQs than on 24-hour recalls, yet there was little underreporting of the percentage of energy from protein. Energy-adjusted measures were therefore less biased than absolute intakes. E (incorrect): Women's energy underreporting was similar to or somewhat larger than men's on both instruments (16 to 20% versus 12 to 14% on recalls).

Source: Subar AF, et al. Using intake biomarkers to evaluate the extent of dietary misreporting in a large sample of adults: the OPEN study. Am J Epidemiol 2003;158(1):1-13. Abstract: underreporting percentages for energy and protein by sex on 24HRs and FFQs versus doubly labeled water and urinary nitrogen; 'There was little underreporting of the percentage of energy from protein'. https://pubmed.ncbi.nlm.nih.gov/12835280/

Answer: C. WHO advises against using them as a means of weight control

A (incorrect): Incorrect. The recommendation covers synthetic and naturally occurring or modified non-nutritive sweeteners, and WHO lists stevia and stevia derivatives among the products it includes. B (incorrect): Incorrect. The guideline Remarks state it is relevant for everyone, including children and pregnant and lactating women, except individuals with existing diabetes, who were outside its scope; she is therefore within it. C (correct): Correct. WHO recommends against the use of non-sugar sweeteners to control body weight or reduce noncommunicable disease risk, because the evidence suggests no long-term benefit in reducing body fat. Reducing the sweetness of the diet overall, with unsweetened beverages or foods with naturally occurring sugars such as fruit, is the suggested alternative. D (incorrect): Incorrect. WHO states that the recommendation does not apply to low-calorie sugars and sugar alcohols (polyols), which contain calories and are not classified as non-sugar sweeteners. E (incorrect): Incorrect. The guideline wording is "WHO suggests that non-sugar sweeteners not be used" (conditional recommendation), based on low-certainty evidence overall; the possibility of confounding and reverse causation in the observational data led to a conservative, conditional rating.

Source: World Health Organization. Use of non-sugar sweeteners: WHO guideline. Geneva: WHO; 2023 (NCBI Bookshelf NBK592246), with WHO news release of 15 May 2023. Recommendation and supporting information: 'WHO suggests that non-sugar sweeteners not be used as a means of achieving weight control or reducing the risk of noncommunicable diseases (conditional recommendation)'; Rationale (low-certainty evidence overall); Remarks (applies to everyone except individuals with existing diabetes; includes stevia and stevia derivatives; does not apply to low-calorie sugars and sugar alcohols). https://www.ncbi.nlm.nih.gov/books/NBK592246/

Answer: E. Elemental iron 30-60 mg plus folic acid 400 micrograms

A (incorrect): 120 mg iron with 2800 micrograms folic acid is the WHO once-weekly intermittent regimen, not a daily dose. B (incorrect): The routine WHO regimen uses 400 micrograms folic acid; 4 mg is a high-dose regimen for specific neural tube defect risk, not routine prevention. C (incorrect): 300 mg is the mass of ferrous sulfate heptahydrate that provides about 60 mg of elemental iron; 300 mg elemental iron is far above the recommendation. D (incorrect): WHO recommends daily iron with folic acid for pregnant women, not iron only after anaemia is diagnosed. E (correct): WHO recommendation A.2.1 is daily oral iron and folic acid with 30-60 mg elemental iron and 400 micrograms folic acid to prevent maternal anaemia, puerperal sepsis, low birth weight and preterm birth.

Source: WHO. WHO recommendations on antenatal care for a positive pregnancy experience: executive summary (WHO/RHR/16.12), 2016. https://iris.who.int/handle/10665/250800 Locator: Table 1, recommendations A.2.1 (daily oral iron 30-60 mg elemental iron and 400 ug folic acid) and A.2.2 with footnotes, p. 3.