Implementing food-based dietary guidelines for - United Nations ...

More documents

Recommendations

Info

S48 in evaluating data of potential use is the sample size needed to provide a high degree of confidence in the level of intake determined to be required. In moving toward harmonizing NIVs, consensus and agreement on what data should be used to establish NIVs (which References 1. King JC, Garza C. Introduction. Food Nutr Bull 2007;28(suppl):S13–5. 2. Murphy SP, Vorster HH. Methods for using nutrient intake values (NIVs) to assess or plan nutrient intakes. Food Nutr Bull 2007;28(suppl):S51–60. 3. Vorster HH, Murphy SP, Allen LH, King JC. Application of nutrient intake values (NIVs). Food Nutr Bull 2007; 28(suppl):S116–22. 4. Atkinson SA, Koletzko B. Determining life-stage groups and extrapolating nutrient intake values (NIVs). Food Nutr Bull 2007;28(suppl):S61–76. 5. Institute of Medicine. Dietary reference intakes: Applications in dietary assessment. Washington, DC: National Academy Press, 2000. 6. Institute of Medicine. Dietary reference intakes for vitamin C, vitamin E, selenium, and carotenoids. Washington, DC: National Academy Press, 2000. 7. Institute of Medicine. Dietary reference intakes for vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc. Washington, DC: National Academy Press, 2001. 8. Institute of Medicine. Dietary reference intakes for calcium, phosphorus, magnesium, vitamin D, and fluoride. Washington, DC: National Academy Press, 1997. 9. Institute of Medicine. Dietary reference intakes for thiamin, riboflavin, niacin, vitamin B 6 , folate, vitamin B 12 , pantothenic acid, biotin, and choline. Washington, DC: National Academy Press, 1998. 10. Institute of Medicine. Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids. Washington, DC: National Academies Press, 2002. 11. Gibson RS. The role of diet- and host-related factors in nutrient bioavailability and thus in nutrientbased dietary requirement estimates. Food Nutr Bull 2007;28(suppl):S77–100. 12. Aggett PJ. Nutrition risk assessment:Setting upper levels and an opportunity for harmonization. Food Nutr Bull 2007;28(suppl):S27–37. A. A. Yates of the possible criteria should be chosen, what datasets are the most appropriate, and how best to adjust when data are missing) represent a major obstacle to overcome. 13. McShane LM, Altman DG, Saueerbrei W. Identification of clinically useful cancer prognostic factors: What are we missing? J Natl Cancer Inst 2005;97:1023–5. 14. Lader EW, Cannon CP, Ohman EM, Newby LK, Sulmasy DP, Barst RJ, Fair JM, Flather M, Freedman JE, Frye RL, Hand MM, Jesse RL, Van de Werf F, Costa F; American Heart Association. The clinician as investigator. Participating in clinical trials in the practice setting. Appendix 1: Fundamentals of study design. Circulation 2004; 109:e302–4. 15. Hill AB. Principles of medical statistics, 9th ed. New York: Oxford University Press, 1971. 16. McKeown-Eyssen GE, Thomas DC. Sample size determination in case-control studies: The influence of the distribution of exposure. J Chronic Dis 1985;38:559–68. 17. Matthews DE, Farewell VT. Understanding and using medical statistics, 2nd revised ed. Basel, Switzerland: Karger, 1988. 18. Rand WM. Variability in planning and assessment: Statistical considerations and models. J Nutr 2004;134(6 suppl):1610S–6S. 19. Rand WM, Young VR. Statistical analysis of nitrogen balance data with reference to the lysine requirement in adults. J Nutr 1999;129:1920–6. 20. Zello GA, Pencharz PB, Ball RO. Phenylalanine flux, oxidation, and conversion to tyrosine in humans studied with L-[I- 13 C]phenylalanine. Am J Physiol 1990;259(6 pt 1):E835–43. 21. Rand WM, Pellett PL, Young VR. Meta-analysis of nitrogen balance studies for estimating protein requirements in healthy adults. Am J Clin Nutr 2003;77:109–27. 22. Lehmann EL. Testing statistical hypotheses, 2nd ed. New York: Wiley, 1986. 23. Kyzas PA, Loizou KT, Ioannidis JP. Selective reporting biases in cancer prognostic factor studies. J Natl Cancer Inst 2005;97:1023–55. 24. Food and Agriculture Organization. Human energy requirements. Report of a Joint FAO/WHO/UNU Expert Consultation. Food and Nutrition Technical Report Series No. 1. Rome: FAO, 2004.
Establishing nutrient intake values Annex Example of deriving an average nutrient requirement (ANR): vitamin A Vitamin A functions in many biological systems: 11-cis-retinal, the active aldehyde form of vitamin A, is part of rhodopsin, required for vision in the brain, for normal growth and maintenance of the cornea and conjunctival membranes of the eye (to prevent xerophthalmia), and as a regulator of genes that form structural proteins, enzymes, and retinol-binding proteins in the blood, including those involved in normal embryonic development and immune function related to cytokines and T and B lymphocyte production [7]. It is not surprising that some of these functions continue normally at comparatively low levels of intake, while others are depressed or inactive, resulting in detectable changes in indicators that denote vitamin A inadequacy. In selecting the indicators or functional outcomes to use to establish an ANR and an NIV x for vitamin A, a number of choices are available (see Annex table 1). In reviewing research and studies available in the year 2000, the DRI process selected as the main criterion to establish adequacy for vitamin A in Canada and the United States adequate liver stores, with adequacy defined as at least 20 µg retinol/g liver tissue. This resulted in an EAR (estimated average requirement, TABLE 1. Possible indicators for evaluating vitamin A adequacy S49 equivalent to an ANR) of 625 µg/day for men and 500 µg/day for women 19 years of age and older [7]. However, it is recognized that significant liver retinol stores are not required for normal function. Thus, dark adaptation was identified as the most sensitive criterion for which adequate data were available to establish an average requirement. There were data supporting the ability of dark adaptation to identify individuals with inadequate intakes of vitamin A, and there were data from individuals inadequate in vitamin A whose dark adaptation was measured and who then were given various levels of vitamin A and underwent additional dark adaptation tests to ascertain at what level of intake the function returned to normal. The level at which dark adaptation returned to normal (defined as at least –4.6 ± 0.3 log candela/m 2 ) in half of those studied (while dark adaptation in the other half remained abnormal) was 300 µg/day. This could be considered the ANR for vitamin A based on dark adaptation. One of the primary limitations of selecting this criterion was that there were only 13 individuals studied in this way. According to this example, when the selected criterion or indicator of adequacy is dark adaptation, the ANR is 300 µg; this is less than half the amount identified if liver stores at the level of 20 µg/g are chosen (650 µg) [7]. This demonstrates that the important question that must be asked in establishing nutrient requirements, and a potential barrier to harmonizing such Function Test Definition of adequacy Dark adaptation Dark adaptometry: final dark-adapted threshold after 35–40 min Circulating levels of vitamin A ≥ – 4.6 ± 0.3 log candela/m 2 Pupillary response test A high threshold in response to incremental pulses of light = low retinal sensitivity due to vitamin A deficiency Serum or plasma retinol concentration; retinol-binding protein concentration Total liver reserves (TLR) Isotope dilution using TLR = F × dose × [(H: D) – 1]; F = efficiency of storage of early administered dose; dose = dose of labeled retinol; H:D = ratio of H to 2 H-retinol in plasma after equilibration Relative dose–response (RDR) Modified relative dose– response (MRDR) Conjunctival impression cytology (CIC) Change in plasma retinol concentration in response to a test dose after 5 h Amount of test dose vitamin A 2 (dehydroretinol) appearing in plasma after 5 h Microscopic examination of periodic acid Schiff–hematoxylin-stained epithelial cells Immune function Humoral antibody responses and cell-mediated immunity Source: Institute of Medicine [7]. Considered insensitive indicators and thus not used TLR ≥ 20 µg/g retinol RDR < 20% MRDR < 20% Lack of abnormal cells Normal number of natural killer cells and normal cytotoxic activity
Page 1 and 2: Contents International harmonizatio
Page 3 and 4: Executive summary Harmonization of
Page 5 and 6: Executive summary [11]. These are l
Page 7 and 8: Executive summary and converted to
Page 9 and 10: Executive summary very rapidly and
Page 11 and 12: Executive summary References Concep
Page 13 and 14: Introduction Janet C. King and Cutb
Page 15 and 16: Introduction References 1. King JC,
Page 17 and 18: Terminology and framework for nutri
Page 27 and 28: Nutrient risk assessment: Setting u
Page 29 and 30: Setting upper levels for nutrient r
Page 39 and 40: Establishing nutrient intake values
Page 47: Establishing nutrient intake values
Page 51 and 52: Methods for using nutrient intake v
Page 53 and 54: Using nutrient intake values to ass
Page 61 and 62: Determining life-stage groups and e
Page 63 and 64: Life-stage groups and nutrient inta
Page 77 and 78: The role of diet- and host-related
Page 79 and 80: Diet- and host-related factors in n
Page 99 and 100:
Diet- and host-related factors in n
Page 101 and 102:
Human nutrition and genetic variati
Page 103 and 104:
Page 105 and 106:
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Application of nutrient intake valu
Page 119 and 120:
Page 121 and 122:
Page 123 and 124:
Trade, development, and regulatory
Page 125 and 126:
Page 127 and 128:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
Page 141 and 142:
Beyond recommendations: Implementin
Page 143 and 144:
Dietary guidelines and nutrient int
Page 145 and 146:
Page 147 and 148:
Page 149 and 150:
Page 151 and 152:
Page 153:
International Dietary Harmonization
show all

Implementing food-based dietary guidelines for - United Nations ...

Create successful ePaper yourself

Delete template?

Save as template?