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United States Department of Agriculture

Agricultural Research Service

Title: FUZZY SETS AND FUZZY DECISION MAKING IN NUTRITION

Authors
item Wirsam, Bernd - ALBAT+WIRSAM SOFTWARE
item Hahn, A - UNIV HANNOVER
item Uthus, Eric
item Leitzmann, Claus - UNIV GIESSEN

Submitted to: European Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 10, 1996
Publication Date: N/A

Interpretive Summary: Fuzzy logic is a mathematical approach to deal with problems, such as deriving nutrient requirements, that can not be defined precisely. Requirements for a nutrient are dependent upon many factors including age, sex, and intake of other nutrients, for example. Dietary intakes of nutrients are such that if a nutrient is given in graded amounts, with all other nutrients constant, there is no definitive border where one intake is deficient and another, slightly higher intake, adequate. It is difficult to look at only one nutrient when making dietary recommendations because most nutrient intake is from foods. Thus, altering the intake of one nutrient by increasing or decreasing the consumption of specific foods, will alter other nutrients. A computer-based program, based on fuzzy logic, was developed to describe the range of intakes of a nutrient from deficiency to excess. The program then calculates, based on the nutrient composition of the food, how closely the total diet of an individual meets all the nutrient requirements as set by the German Society of Nutrition. Because this is a computer-based system, alterations in the diet are suggested if the diet does not meet requirements. The program takes into consideration the effect of dietary changes on all nutrients and optimizes the diet accordingly. The suggested dietary alterations are usually small but nevertheless allow the diet to meet recommendations. It is important that the suggested alterations be small because the fewer the suggested changes in a diet, the greater the chance a person will accept the changes. This approach to nutrition education is useful to all people who are concerned about meeting nutrient recommendations.

Technical Abstract: Fuzzy logic is a mathematical approach to deal with systems that can not be defined precisely. Nutrient requirements fall into this category. Dietary intakes of nutrients are such that if a nutrient is given in graded amounts, with all other nutrients constant, there is no definitive border where, for example, one intake is deficient and another, slightly higher intake, adequate. Thus, fuzzy sets were developed that describe the range of intakes of a nutrient ranging from deficiency to excess. Then, based on these fuzzy sets and knowing the nutrient composition of the food, the Prerow value was determined. The Prerow value is an index of how closely the diet of an individual meets all the nutrient requirements as set by the German Society of Nutrition. Because this is a computer-based system, alterations in the diet are suggested if the diet does not meet requirements. The suggested dietary alterations are usually small but nevertheless allow the diet to meet recommendations. It is important that the suggested alterations be small because the fewer the suggested changes in a diet, the greater the chance a person will accept the changes.

Last Modified: 10/31/2014
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