Historical changes in the mineral content of fruit and vegetables in the UK from 1940 to 2019: a concern for human nutrition and agriculture

Abstract

Micronutrient malnutrition is widespread and is linked with diets low in fruit and vegetables. However, during the twentieth century, declines in essential minerals in fruits and vegetables were reported in the UK and elsewhere. A new analysis of long-term trends of the mineral content of fruits and vegetables from three editions of the UK’s Composition of Foods Tables (1940, 1991 and 2019) was undertaken. All elements except P declined in concentrations between 1940 and 2019 – the greatest overall reductions during this 80-year period were Na (52%), Fe (50%), Cu (49%) and Mg (10%); water content increased (1%). There could be many reasons for these reductions, including changes in crop varieties and agronomic factors associated with the industrialisation of agriculture. Increases in carbon dioxide could also play a role. We call for a thorough investigation of these reductions and steps to be taken to address the causes that could contribute to global malnutrition.

Keywords:

• Fruit
• vegetable
• mineral
• nutritional quality
• agroecology
• historical changes

Acknowledgments

The authors acknowledge the valuable comments on the manuscript provided by Don Davis and Julia Wright. The authors thank Alun Owen, Statistician at Sigma, Coventry University for his invaluable advice.

A. M. confirms that she had full access to all the data in the study and had final responsibility for the decision to submit for publication.

Disclosure statement

The authors report no conflict of interest.

Notes

1 One DALY can be thought of as one lost year of ‘healthy’ life. The sum of these DALYs across the population, or the burden of disease, can be thought of as a measurement of the gap between current health status and an ideal health situation where the entire population lives to an advanced age, free of disease and disability (World Health Organisation).

2 Tomatoes and peppers are technically fruits but are included as vegetables in the COF tables.

3 The fruits and vegetables included in the COF represent common sources in the UK at the time of analysis and could include foods grown in the UK or abroad.

4 Nutrient density is the content of mineral nutrient in the fruit or vegetable as a proportion of the energy content.

5 Selenium has not been included in Tables 1 and 2 because it was only added recently to the Composition of Foods Tables.

6 Biofortification: the process of increasing the bioavailable concentrations of an element in edible portions of crop plants through agronomic intervention or genetic selection.

Additional information

Funding

There was no specific funding for this article, the work was done on a voluntary basis by AM and supported by Coventry University for LT and FR.