Related Experiment Video
Updated: Sep 17, 2025

The Caco-2 Cell Bioassay for Measurement of Food Iron Bioavailability
Published on: April 28, 2022
Diet optimization: modeling iron and zinc absorption by nonlinear programming and piecewise linear approximation
Dominique van Wonderen1, Johanna C Gerdessen2, Peter Kirst2
1Wageningen Social & Economic Research, Wageningen University & Research, Wageningen, The Netherlands.
Background:
The accuracy of the calculation of absorbable nonheme iron and zinc content in diet-model-generated menu plans can be improved by using nonlinear absorption equations. The resulting diet models cannot be solved with standard linear programming software.
Objective:
The aim of this study was to evaluate the effectiveness of nonlinear programming (NLP) and piecewise linear approximation (PLA) for solving diet models with nonlinear equations for nonheme iron and zinc absorption.
Methods:
A mixed-integer and a continuous diet model were developed to optimize absorbable iron and zinc intake, using different absorption equations available from the literature. Model input data were obtained from the National Health and Nutrition Examination Survey. Various diet plans were then generated applying both NLP and PLA techniques. Evaluation criteria included solution quality and computational efficiency.
Results:
For the mixed-integer diet model, PLA found accurate solutions within minutes, outperforming NLP in consistency and solution quality. NLP frequently hit the 1-h time limit and did not always find the best observed solution. In the worst cases, NLP either found no solution or the deviation was as large as 2.1 mg for absorbable iron. For absorbable zinc, the maximum deviation was only 0.2 mg. For the continuous diet model, NLP and PLA performed equally well in most cases.
Conclusions:
This study provides practical examples for researchers who seek to improve the accuracy of their diet models through the implementation of nonheme iron and zinc absorption equations using either NLP or PLA.
More Related Videos
04:54Assessing Mineral Availability in Fish Feeds using Complementary Methods Demonstrated with the Example of Zinc in Atlantic Salmon
Published on: October 29, 2021
06:00Optimization of the Epimedii Folium Mutton-Oil Processing Technology and Testing Its Effect on Zebrafish Embryonic Development
Published on: March 17, 2023
Related Concept Videos
Physiological Pharmacokinetic Models: Assumption with Protein Binding
Parameters Affecting Nonlinear Elimination: Zero-Order Input, First-Order Absorption and Two-Compartment Model
When a drug is administered through a constant intravenous infusion and eliminated via nonlinear pharmacokinetics, it follows zero-order input. For example, oral drugs undergo first-order absorption upon administration and are eliminated through nonlinear pharmacokinetics.
In the case of subcutaneously administered drugs,...
One-Compartment Open Model for IV Bolus Administration: Estimation of Elimination Rate Constant, Half-Life and Volume of Distribution
One-Compartment Open Model for Extravascular Administration: Zero-Order Absorption Model
Zero-order absorption maintains a steady rate irrespective of the amount of drug left to be absorbed, making it a constant process. In the...
Model-Independent Approaches for Pharmacokinetic Data: Noncompartmental Analysis
One important characteristic of noncompartmental analyses is that drug exposure increases proportionally with increasing doses. This...
Inflammatory Bowel Disease III: Diagnostic Studies and Management I-Nutritional Therapy
Diagnostic studies
A colonoscopy is the definitive screening test, distinguishing ulcerative colitis from other colon diseases with similar symptoms. During a colonoscopy test, inflamed mucosa with exudate ulcerations can be observed, and biopsies are taken to determine the histologic characteristics of the...