Point of view: Energy factors for food labelling and other purposes should be derived in a consistent fashion for all food components

Abstract

In Australia, the process by which food energy factors are derived for food labelling purposes is under review. One of the questions of international relevance is whether energy factors should be derived using a definition of metabolisable energy (ME) or a definition of net (metabolisable) energy (NME), or some mixture of the two. ME describes the food energy available for heat production and body gains. NME deducts obligatory thermogenesis from ME in an attempt to reflect the food energy that can be converted to ATP energy within the body. Some countries use NME to derive energy factors for novel food ingredients such as sugar alcohols and polydextrose, but continue to use ME for protein, fat, carbohydrate, and alcohol. The present paper puts a case for using a consistent system (ME at the present time) for all food components. Reasons for this include: consistent application to all food components allows valid comparisons between products; food energy values and estimates of energy expenditure (food energy requirements) should be directly comparable; NME does not account for all sources of thermogenesis; differences between ME and NME for sugar alcohols and polydextrose are small in the context of the whole diet; and the ME system does not preclude information about metabolic efficiency being provided as additional information. Any major change to the way in which energy values are expressed (e.g. global adoption of the NME system) merits wide discussion among the human nutrition community. One aim of this present paper is to stimulate this discussion.Energy factors: Food labelling: Metabolisable energy: Net (metabolisable) energyThe energy value of foods is an important issue for consumers (who may be concerned about energy intakes for body weight management), for industry (for product development and labelling) and for the scientific community and health professionals (for educational, clinical and experimental applications).In Australia, the process by which energy factors for food components are derived for food labelling purposes is under review (Australia and New Zealand Food Authority, 1999). This was prompted by a lack of clear definition of how currently prescribed energy factors were derived, and lack of guidance for establishing factors for novel food components. The key questions posed were: (1) whether energy factors should be derived using a definition of metabolisable energy (ME) or net (metabolisable) energy (NME); and (2) whether energy factors should be derived in a consistent fashion for all food components. The answers to these questions have international relevance.The consistent application of the ME system is contrary to the use by some countries of ME for conventional nutrients and NME for polyols and polydextrose, while the NME system is not consistently applied anywhere in the world. The present paper puts a case for using a consistent approach to derive energy factors for all food components, conventional and novel, and for using ME as the basis of derivation at the present time. The...

Physiological aspects of energy metabolism and gastrointestinal effects of carbohydrates

“…The evidence reviewed is primarily from human studies. Figure 1, which is a modification of previous diagrams (Warwick and Baines, 2000;Livesey, 2001;FAO, 2003), shows the flow of energy through the body. It presents a conceptual framework for considering energy values of foods and individual macronutrients.…”

Use of the net metabolizable energy values for labeling of infant formulas and foods—potential issues

“…Although an in depth review of NME is beyond the scope of this paper (the reader is referred to the discussions of Warwick and Baines, 2000and Livesey, 2001, 2004a, it is instructive to look at specific components of ME and NME to see where there are similarities or differences between the growing infant/young child and the adult. Like ME factors, the NME factors have been determined in adults.…”

“…Pros and cons of using the NME approach in food labeling of infant formulas and foods for infants and children A number of pros and cons of using NME factors in food labeling have been raised in the literature (Warwick and Baines, 2000;Livesey, 2001Livesey, , 2004a. It seems appropriate to comment on five selected areas in which pros and cons of using NME, especially in infant formula labeling, may be different from those anticipated for labeling of foods in general.…”

“…There has been a lively debate in the literature about the desirability of using net metabolizable energy (NME) rather than the classic metabolizable energy (ME) Atwater factors to calculate energy values of foods for labeling purposes (Warwick and Baines, 2000;Livesey, 2001). This proposal also has been discussed in recent FAO/WHO/UNU working groups and consultations.…”

O valor energético dos alimentos: exemplo de uma determinação experimental, usando calorimetria de combustão

“…As quantidades dos nutrientes (em gramas) maioritariamente usados pelo corpo humano para a obtenção de energia (proteínas, lípidos e glícidos) são multiplicadas, respectivamente, pelos factores 4, 9 e 4 (em kcal.g -1 ), para a obtenção do valor energético do alimento. Embora este método de estimativa possua algumas desvantagens, [3][4][5] tais como basear-se no conceito de energia metabolizável, 6 não fazer distinção entre os vários tipos de glícidos e proteínas, não contabilizar o valor energético das fibras alimentares fermentáveis (solúveis) e não funcionar correctamente para bebidas alcoólicas, ainda é actualmente usado pela indústria alimentar. Nos Estados Unidos da América 7,8 e na União Europeia, 9,10 os métodos oficiais de estimativa do valor energético dos alimentos baseiam-se no método descrito, com alguns refinamentos adicionais ao nível da utilização de factores mais específicos para os vários tipos de nutrientes, de acordo com as suas origens.…”