Hostname: page-component-7c8c6479df-r7xzm Total loading time: 0 Render date: 2024-03-27T12:04:18.178Z Has data issue: false hasContentIssue false

Protein/energy ratios of current diets in developed and developing countries compared with a safe protein/energy ratio: implications for recommended protein and amino acid intakes

Published online by Cambridge University Press:  02 January 2007

D Joe Millward*
Affiliation:
Centre for Nutrition and Food Safety, School of Biological Sciences, University of Surrey, Guildford, Surrey, GU2 5XH, UK
Alan A Jackson
Affiliation:
Institute of Human Nutrition, University of Southampton, Southampton, SO16 6YD, UK
*
*Corresponding author: Email D.Millward@surrey.ac.uk
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Revised estimates of protein and amino acid requirements are under discussion by the Food and Agriculture Organization (FAO)/World Health Organizaion (WHO), and have been proposed in a recent report on Dietary Reference Intakes (DRIs) from the USA. The nature and magnitude of these requirements are not entirely resolved, and no consideration has been given to the potential influence of metabolic adaptation on dietary requirements. We have examined the implications of these new values, and of the conceptual metabolic framework in which they are used, for defining the nutritional adequacy of protein intakes in developed and developing countries. We have expressed proposed values for protein requirements in relation to energy requirements, predicted for physical activity levels of 1.5, 1.75 and 2.0 times basal metabolic rate, in order to generate reference ratios for protein energy/total energy (reference P/E ratio) as a function of age, body weight, gender and physical activity level. Proposed values for amino acid requirements have been used to adjust the available digestible P/E ratio of foods and diets for protein quality. Focusing on the diets of UK omnivores and vegetarians and on diets in India, the risk of protein deficiency is evaluated from a comparison of P/E ratios of metabolic requirements with protein-quality-adjusted P/E ratios of intakes. A qualitative and conservative estimate of risk of deficiency is made by comparing the adjusted P/E ratio of the intake with a reference P/E ratio calculated for age, body weight, gender and physical activity according to FAO/WHO/United Nations University. A semi-quantitative estimate of risk of deficiency has also been made by the cut point approach, calculated as the proportion of the intake distribution below the mean P/E ratio of the requirement. Values for the quality-adjusted P/E ratio of the diet range from 0.126 for the UK omnivore diet to 0.054 for a rice-based diet of adults in West Bengal, which is lysine-limited, falling to 0.050 for 1-year-old children. The reference P/E ratio for men and women increases with age, is higher for females than males, is higher for small compared with large adults at any age and decreases with physical activity. Thus if a particular diet is potentially limiting in protein, protein deficiency is most likely in large, elderly sedentary women followed by the adolescent female and least likely in moderately active young children, the opposite of what has usually been assumed. Within the currently accepted framework, the diets do not meet the protein needs of the entire population of the UK, have a significant risk of deficiency throughout India for all except extremely active small adults, and are grossly inadequate for all population groups, apart from physically active young children in West Bengal, regardless of body weight or level of food intake. The lysine limitation of the cereal-based Indian diets is dependent on the choice of lysine requirement values from the published range. We consider that the value selected is too high, because of uncertainties and inconsistencies in the approaches used. A more appropriate choice from the lower end of the range would remove the lysine limitation of cereal-based diets, and reduce some of the perceived risk of deficiency. However, diets remain limited by the amount of digestible protein for many population groups, especially in West Bengal. In the context of risk management, one option would be to accept the current values and the conceptual metabolic framework within which they have been derived. This would have major implications for the supplies of high-quality protein to the developing countries. An alternative option would be to re-evaluate the currently proposed values for the requirements for protein and amino acids. We conclude that the choice of values for the adult lysine requirement should be re-evaluated and that serious consideration should be given to the extent to which adaptive mechanisms might enable the metabolic requirement for protein to be met from current intakes. This will entail a better understanding of the relationships between dietary protein and health.

Type
Research Article
Copyright
Copyright © CAB International 2004

References

1World Health Organization (WHO). Preparation and Use of Food-Based Dietary Guidelines. Report of a Joint Food and Agriculture Organization/WHO Consultation. Technical Report Series No. 880. Geneva: WHO, 1998.Google Scholar
2Food and Agriculture Organization (FAO)/World Health Organization (WHO)/United Nations University (UNU). Energy and Protein Requirements. Report of a Joint FAO/WHO/UNU Expert Consultation. Technical Report Series No. 724. Geneva: WHO, 1985; 150–60.Google Scholar
3Millward, DJ, Bowtell, JL, Pacy, P, Rennie, MJ. Physical activity, protein metabolism and protein requirements. Proceedings of the Nutrition Society 1994; 53: 223–40.Google Scholar
4Waterlow, JC. Nutritional adaptation in man: general introduction and concepts. American Journal of Clinical Nutrition 1990; 51: 259–63.Google Scholar
5Hegsted, DM. From chick nutrition to nutrition policy. Annual Review of Nutrition 2000; 20: 119.Google Scholar
6Young, VR, Borgonha, S. Nutritional adaptation (genetic, physiological and behavioural): implications for requirements. In: Fitzpatrick, DW, Anderson, JE, L'Abbé, ML, eds. From Nutritional Science to Nutrition Process for Better Global Health. Ottawa: Canadian Federation of Biological Societies 1998; 57160.Google Scholar
7Jackson, AA. Limits of adaptation to high dietary protein intakes. European Journal of Clinical Nutrition 1999; 53(Suppl. 1): S4452.Google Scholar
8James, WPT, Schofield, EC. Human Energy Requirements. Oxford: Oxford University Press, 1990.Google Scholar
9Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients). Washington, DC: National Academy Press, 2002.Google Scholar
10Rand, WM, Pellett, PL, Young, VR. Meta-analysis of nitrogen balance studies for estimating protein requirements in healthy adults. American Journal of Clinical Nutrition 2003; 77: 109–27.Google Scholar
11Schofield, WN, Schofield, C, James, WPT. Basal metabolic rate: review and prediction. Human Nutrition: Clinical Nutrition 1985; 39C: 196.Google Scholar
12Jackson, AA, Margetts, BM. Protein intakes in the adult population of the UK. International Journal of Food Science and Nutrition 1993; 44: 95104.Google Scholar
13Pellett, PL. World essential; amino acid supply with special attention to South-East Asia. Food and Nutrition Bulletin 1996; 17: 204–34.Google Scholar
14Food and Agriculture Organization, (FAO)/World Health Organization. Protein Quality Evaluation in Human Diets. FAO Food and Nutrition Paper 51. Rome: FAO, 1991.Google Scholar
15Rosegrant, MW, Leach, N, Gerpacio, RV. Alternative futures for world cereal and meat consumption. Proceedings of the Nutrition Society 1999; 58: 219–34.Google Scholar
16Graham, GG, Morales, E, Placko, RP, Maclean, WC. Nutritive value of brown and black beans for infants and small children. American Journal of Clinical Nutrition 1979; 32: 2362–6.Google Scholar
17Graham, GG, Lembcke, J, Morales, E. Quality-protein maize as the sole source of dietary protein and fat for rapidly growing young children. Pediatrics 1979; 85: 8591.Google Scholar
18Maclean, WC, De Romana, GL, Placko, RP, Graham, GG. Protein quality and digestibility of sorghum in preschool children: balance studies and plasma free amino acids. Journal of Nutrition 1981; 111: 1928–6.Google Scholar
19MacFarlane, G, Cummings, JH. The colonic flora, fermentation, and large bowel digestive function. In: Phillips, S, Pemberton, JH, Shorter, RG, eds. The Large Intestine: Physiology, Pathophysiology and Disease. New York: Raven Press, 1991; 5192.Google Scholar
20Fuller, MF, Milne, A, Harris, CI, Reid, TMS, Keenan, R. Amino acid losses in ileostomy fluid on a protein-free diet. American Journal of Clinical Nutrition 1994; 59: 70–3.Google Scholar
21Jackson, AA. Salvage of urea nitrogen in the large bowel: functional significance in metabolic control and adaptation. Biochemical Society Transactions 1998; 26: 231–6.Google Scholar
22Metges, CC. Contribution of microbial amino acids to amino acid homeostasis of the host. Journal of Nutrition 2000; 130: 1857S–64S.Google Scholar
23Millward, DJ, Forrester, T, Ah-Sing, E, Yeboah, N, Gibson, N, Badaloo, A et al. The transfer of 15N from urea to lysine in the human infant. British Journal of Nutrition 2000; 83: 505–12.Google Scholar
24Millward, DJ. Nutrition Discussion Forum. Urine nitrogen as an independent validatory measure of dietary intake: potential errors due to variation in magnitude and type of protein intake. British Journal of Nutrition 1997; 77: 141–4.Google Scholar
25Bingham, SA. Nutrition Discussion Forum. Urine nitrogen as an independent validatory measure of protein intake. British Journal of Nutrition 1997; 77: 144–8.Google Scholar
26Millward, DJ. The nutritional value of plant based diets in relation to human amino acid and protein requirements. Proceedings of the Nutrition Society 1999; 58: 249–60.Google Scholar
27Rand, WM, Young, VR. Statistical analysis of N balance data with reference to the lysine requirement in adults. Journal of Nutrition 1999; 129: 1920–6.Google Scholar
28Dewey, KG, Beaton, G, Fjeld, C, Lonnerdal, B, Reeds, P. Protein requirements of infants and children. European Journal of Clinical Nutrition 1996; 50: 5119–50.Google Scholar
29Kurpad, AV, El-Khoury, AE, Beaumier, L, Srivatsa, A, Kuriyan, R, Raj, T et al. . An initial assessment, using 24-h [13C]leucine kinetics, of the lysine requirement of healthy adult Indian subjects. American Journal of Clinical Nutrition 1998; 67: 5866.Google Scholar
30Kurpad, AV, Raj, T, EI-Khoury, A, Beaumier, L, Kuriyan, R, Srivatsa, A et al. Lysine requirements of healthy adult Indian subjects, measured by an indicator amino acid balance technique. American Journal of Clinical Nutrition 2001; 73: 900–7.Google Scholar
31Kurpad, AV, Regan, MM, Raj, T, EI-Khoury, A, Kuriyan, R, Vaz, M et al. Lysine requirement of healthy adult Indian subjects receiving long-term feeding, measured with a 24-h indicator amino acid oxidation and balance technique. American Journal of Clinical Nutrition 2002; 76: 404–12.Google Scholar
32Zello, GA, Pencharz, PB, Ball, RO. Dietary lysine requirement of young adult males determined by oxidation of L-[1-13C]phenylalanine. American Journal of Physiology 1993; 264: E677–85.Google Scholar
33Duncan, AM, Ball, RO, Pencharz, PB. Lysine requirement of adult males is not affected by decreasing dietary protein. American Journal of Clinical Nutrition 1996; 64: 718–25.Google Scholar
34Kriengsinyos, W, Wykes, LJ, Ball, RO, Pencharz, PB. Oral and intravenous tracer protocols of the indicator amino acid oxidation method provide the same estimate of the lysine requirement in healthy men. Journal of Nutrition 2002; 132: 2251–7.Google Scholar
35Millward, DJ, Fereday, A, Gibson, NR, Pacy, PJ. Human adult protein and amino acid requirements: [1-13C]leucine balance evaluation of the efficiency of utilization and apparent requirements for wheat protein and lysine compared with milk protein in healthy adults. American Journal of Clinical Nutrition 2000; 72: 112–21.Google Scholar
36Millward, DJ, Fereday, A, Gibson, NR, Cox, MC, Pacy, PJ. Efficiency of utilization of wheat and milk protein and apparent lysine requirements determined by a single-meal [1-13C]leucine balance protocol. American Journal of Clinical Nutrition 2002; 76: 1326–34.Google Scholar
37Butte, NF, Hopkinson, JM, Wong, WW, Smith, EO, Ellis, KJ. Body composition during the first 2 years of life: an updated reference. Pediatric Research 2000; 47: 578–85.Google Scholar
38Ellis, KJ, Shypailo, RJ, Abrams, SA, Wong, WW. The reference child and adolescent models of body composition. A contemporary comparison. Annals of the New York Academy of Sciences 2000; 904: 374–82.Google Scholar
39Platt, BS, Miller, DS, Payne, PR. Protein values of human food Recent Advances in Human Nutrition. In: Brock, JF, ed. Recent Advances in Human Nutrition. Boston, MA: Little Brown 1961; 351–74.Google Scholar
40 Institute of Medicine. Dietary Reference Intakes: Application in Dietary Assessment [online], 2000. Available at http://www.nap.edu/books/0309071836/html.Google Scholar
41Beaton, GH. Criteria of an adequate diet. In: Shils, ME, Olson, JA, Shike, M, eds. Modern Nutrition in Health and Disease, 8th ed. Philadelpia, PA: Lea & Febiger, 1994; 1491–505.Google Scholar
42Beaton, GH. Recommended dietary intakes: individuals and population. In: Shils, ME, Olson, JA, Shike, M, Ross, AC, eds. Modern Nutrition in Health and Disease, 9th ed. Baltimore MD: Williams & Wilkins, 1999; 1705–25.Google Scholar
43Henderson, L, Gregory, J, Irving, K, Swan, G. The National Diet and Nutrition Survey: Adults aged 19 to 64 years. Vol. 2. Energy, Protein, Carbohydrate, Fat and Alcohol Intake. London: Office for National Statistics and Food Standards Agency 2003; (http://www.foodstandards.gov.uk/multimedia/pdfs/ndnsprintedreport.pdf).Google Scholar
44Torun, B, Davies, PSW, Livingstone, MBE, Paolisso, M, Sackett, R, Spur, GB. Energy requirements and dietary energy recommendations for children and adolescents 1 to 18 years old. European Journal of Clinical Nutrition 1996; 50(Suppl. 1) S3781.Google Scholar
45Hayter, J, Henry, CJK. A re-examination of BMR predictive equations. European Journal of Clinical Nutrition 1994; 48: 702–10.Google Scholar
46Shetty, PS, Henry, CJ, Black, AE, Prentice, AM. Energy requirements of adults: an update on basal metabolic rates (BMRs) and physical activity levels (PALs). European Journal of Clinical Nutrition 1996; 50 (Suppl. 1) S1123.Google Scholar
47Young, VR, Scrimshaw, NS, Pellett, PL. Significance of dietary protein source in human nutrition: animal and/or plant proteins? In: Waterlow, JC, Armstrong, DG, Fowden, L, Riley, R, eds. Feeding a World Population of More than Eight Billion People: A Challenge to Science. New York: Oxford University Press in association with Rank Prize Funds, 1998; 205–21.Google Scholar
48Food and Agriculture Organization (FAO)/World Health Organization (WHO). Energy and Protein Requirements. Report of a Joint FAO/WHO Ad Hoc Expert Committee Technical Report Series No. 522. Geneva: WHO, 1973.Google Scholar
49Jones, EM, Bauman, CA, Reynolds, MS. Nitrogen balances in women maintained on various levels of lysine. Journal of Nutrition 1956; 60: 549–59.Google Scholar
50Young, VR. Nutritional balance studies: indicators of human requirements or adaptive mechanisms. Journal of Nutrition 1986; 116: 700–3.Google Scholar
51Millward, DJ, Jackson, AA, Price, G, Rivers, JPW. Human amino acid and protein requirements: current dilemmas and uncertainties. Nutrition Research Reviews 1989; 2: 109–32.Google Scholar
52Bolourchi, S, Friedmann, CM, Mickelsen, O. Wheat flour as a source of protein for human subjects. American Journal of Clinical Nutrition 1968; 21: 827–35.Google Scholar
53Edwards, CH, Booker, LK, Rumph, CH, Wright, WG, Ganapathy, SN. Utilization of wheat by adult man: nitrogen metabolism, plasma amino acids and lipids. American Journal of Clinical Nutrition 1971; 24: 181–93.Google Scholar
54Millward, DJ. Metabolic demands for amino acids and the human dietary requirement: Millward and Rivers (1988) evisited. Journal of Nutrition 1998; 128(Suppl. 12): 2563S–76S.Google Scholar
55Millward, DJ. An adaptive metabolic demand model for protein and amino acid requirements. British Journal of Nutrition 2003; 90: 249–60.Google Scholar
56Millward, DJ. A protein-stat mechanism for the regulation of growth and maintenance of the lean-body mass. Nutrition Research Reviews 1995; 8: 93120.Google Scholar