Research and Development

Nutri-Flow Dietary Guide – Research and Development

How it works?

The overall idea is based on the idea of a nutrient dense diet. Nutrient density describes the amount of protective nutrients in an energy unit.

Nutrient density – what is it?

Figure 1 represents three different diets and their nutrient densities. Diet A is a starting point for a person who wants to lose some weight. Diet C describes a normal weight loss diet without professional guidance. You just eat less and get less energy. As the diagram shows, you get also less protective nutrients during this kind of diet. Diet B is an optimal way to lose weight. Nutri-Flow Dietary Guide will automatically guide to reduce foods with “empty energy” with small steps.

Many people with normal weights have diets like diet C as shown in diagram. In this case, you don not have to lose weight, but you might need to change your eating habits to gain a diet like diet B.

Figure 1. Nutrient density

Advanced calculation methods

The heart of Nutri-Flow Dietary Guide consists of a Fuzzy Expert System (FES), and a Genetic Algorithms Optimization (GA). The first one, FES, is the most important module. It deals with uncertain and imprecise input variable values, it uses knowledge of a licensed nutritionist, to assess state of a diet, and to determine which foods or beverages should be reduced, added or kept on the same level as they were.

The latter module, GA, optimizes the portion sizes for the foods and the beverages to be altered from the original diet. The goal of the optimization process is to find portion sizes which reduce the gap between recommendation and actual diet. The changes are also compared to the original diet to keep it in a reasonable level.

Figure 2 represents the structure of the system.


Figure 2. Structure of the system

Academic research

Development of Nutri-Flow Dietary Guide has started in 2004. During the development process there have been done several final thesis from Oulu UAS and two Master’s thesis from Oulu University.

Currently, Petri Heinonen, M.Sc (tech) is doing research work for his PhD thesis. The goal of the research work is to find more sophisticated and robust ways for data acquiring, and make the calculation process more efficient and more reliable.

For more information about this current research and development project, please contact Petri Heinonen:, tel. +358 400 858 719


Nutritional aspect

During the development process there has been a licenced nutritionist making sure that all the results follow the official nutritional recommendations, and the system uses the results from the latest Finnish, Nordic, and global research work.

Currently, there is one responsible licenced nutritionist monitoring the further development work.



1. Heinonen P, Mannelin M, Iskala H, Sorsa, Juuso E. Development of a Fuzzy Expert System for a Nutritional Guidance Application, Proc. Joint 2009 International Fuzzy Systems Association World Congress and 2009 European Society of Fuzzy Logic and Technology Conference, Lisbon, Portugal, July 20-24, 2009, pp. 1685-1690.

2. Heinonen P, Juuso EK, Development of a Genetic Algorithms Optimization Algorithm for a Nutritional Guidance Application, 2016 9th EUROSIM Congress on Modelling and Simulation, Oulu, Finland, Sept. 12-16, 2016, pp. 56-61, doi: 10.1109/EUROSIM.2016.58.


Contact us:

Petri Heinonen
Project Manager
petri.heinonen (at)
tel. +358 400 858 719