LCA Food 2012 in Saint Malo, France! - Manifestations et colloques ...

PARALLEL SESSION 4B: DIET 8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
Nutrition in LCA: Are nutrition indexes worth using?
MTT Agrifood Research Finland, E-mail: merja.saarinenr@mtt.fi
Merja Saarinen
ABSTRACT
Environmental impact of food is mostly considered on a mass basis, although nutrition undoubtedly is one of the main functions of
food. The paper develops a methodology to combine nutritional and environmental aspects in food LCA. The usability of nutrition
indexes is tested and discussed. The nutrition indexes tested were Nutrient Rich Food, NRF9, Naturally Nutrient Rich, NNR15, and
Nutrient Adequacy Ratio, NAR15. They are intended for application to all types of food. The test calculation included several foods
from several product groups based on general nutrient composition data and environmental impact data. Preliminary results show that
environmental impact seems to dominate and strengthen the recommendation to restrict animal-based foods and favour plant-based
foods. However, inclusion of recommended and limited nutrients is a necessity before further application of the method, and a reformulation
of the nutrient composition of the index has also to be considered.
Keywords: food, nutrient index, LCA
1. Introduction
According to the ISO 14040, standard functions of the system being studied shall be clearly specified, and
comparisons between systems shall be made on the basis of the same function(s), quantified by the same
functional unit(s) in the form of their reference flows. Selected FU(s) should go together with a goal and
scope of the study.
Currently environmental impact of food is mostly considered on a mass basis in public debate and
scientific discussion. There is however a growing interest in considering nutrition and environment
simultaneously (e.g. Saarinen et al., 2012; Schau and Fet, 2008; Smedman et al., 2011). This can be seen as
an outgrowth of increasing efforts to inform consumers about sustainability of food products instead of using
LCA as a tool to improve the production chain. As long as environmental sustainability of food products is
considered a field for improving eco-efficiency of producers, nutrition will be neglected. But consumer
information on sustainable food choices is valueless without considering nutrition. There are also several
other functions associated with eating that are very relevant to consumers, like pleasure, social interaction
etc., but nutrition is the basic function of food when comparisons are made in the context of sustainability.
As comparison between products is made on the basis of the same functional units, opportunities to use
“nutritional functional units” should be carefully considered.
The paper develops a methodology to combine nutritional and environmental aspects in food LCA.
Climate change and eutrophication potential were used as examples of the environmental category. The
usability of nutrition indexes is tested and discussed.
2. Methods
The nutrition indexes tested were Nutrient Rich Food, NRF9, Naturally Nutrient Rich, NNR, and Nutrient
Adequacy Ratio, NAR16 (Drewnowski and Fulgoni, 2007). NAR16 includes 16 nutrients, but the Finnish
nutrient database does not provide information on pantothenic acid (B5), so in this study NAR16 included 15
nutrients as NAR15. NNR also includes 15 nutrients, and is thus NNR15. These indexes combine recommended
nutrients and quantify an average share of nutrients in 100 g of a product (or any other amount of
food) from their daily nutrient recommendation. The indexes, their nutrient composition and formulas, are
presented in (Table 1).
Other indexes consisting of nutrients to recommend were also considered, but the lack of nutritional data
restricted their use. From the point of view of the science of nutrition, indexes that include nutrients to be
recommended and nutrients to be limited provide the most accurate feature of the nutritional value of foods,
and therefore basically both types of nutrient should be considered. In this study, indexes consisting of both
nutrients to recommend and nutrients to limit were applied to nutrient calculations, but not to environmental
assessment because they confer negative values to some foods (not shown in the paper). Negative values are
not directly applicable in LCA as they result in a negative environmental impact. Indexes that proportion
nutrients to energy content of food (i.e. nutrient density indexes) were also applied to nutrient calculations,
but not to environmental assessment. They basically are suitable for nutrient calculation in situations where
energy needs to be limited. In such a case energy is regarded as a disadvantage. Accordingly, high energy
content reduces the nutrient density value, and low energy content increases the nutrient density value. If
these are used as a FU in the LCA, the interpretation would be reversed so that energy would be an advantage;
high energy content would result in lower environmental impact than lower energy content. Indexes
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