Temporal Change in Iron Content of Vegetables and Legumes in Australia: A Scoping Review

Abstract

Studies in UK and US have reported a temporal decline in the iron content of plant-based foods. Limited research on this topic has been conducted in Australia. The aim of this scoping review was to provide a comprehensive evaluation on the temporal change in iron content of Australian vegetables and legumes from 1900 onward. A systematic search of electronic databases, websites, backward reference searching, and Australian food composition tables was conducted. A total of 34 articles and six versions of Australian food composition databases published between 1930s to 2021, were included in this review. Overall, iron content of vegetables and legumes were assessed at limited time points and geographical origin, cultivars, sampling and analytical techniques varied across studies. The majority of vegetables had similar iron content between two or more timepoints but decreases of 30–50% were noted for sweet corn, red-skinned potatoes, cauliflower and green beans while increases of 150–300% were seen for Hass avocadoes, mushrooms and silverbeet. More pronounced reductions in iron content were observed for legumes, with higher and more variable values reported pre-2000 compared to recent years. Due to limited data and variations in sampling and analytical techniques, no definitive conclusions could be established. As plant-based diets are becoming more popular, consistent monitoring of the nutrient composition of staple plant-based foods is strongly recommended.

Elemental Profiles of Legumes and Seeds in View of Chemometric Approach

“…However, in our current research, Fe content in beans was 3.72 mg/100 g, while Cabrera et al [18] determined almost two times higher Fe content of 6.25 mg/100 g. Similarly, in the case of Zn, they [18] found almost a 100% higher level of Zn in beans (3.97 mg/100 g) than in our study (1.91 mg/ 100 g). These results might be in accordance with the findings of Eberl et al [19], who stated that studies in the UK and the US have reported a temporal decline in the Fe content of plant-based foods. They found significant decreases in Fe content in legumes, with higher and more variable values reported pre-2000 compared to recent years [19].…”

“…These results might be in accordance with the findings of Eberl et al [19], who stated that studies in the UK and the US have reported a temporal decline in the Fe content of plant-based foods. They found significant decreases in Fe content in legumes, with higher and more variable values reported pre-2000 compared to recent years [19]. However, Cabrera et al [18] noted similar to ours Fe concentration in sunflower seeds, i.e., 4.09 mg/100 g. Manganese levels varied between each analyzed group, with the highest values noted for soybean (2.21 mg/100 g) among legumes, and poppy seeds (7.2 mg/100 g).…”

Investigation into the Physicochemical and Textural Properties of an Iron-Rich 3D-Printed Hybrid Food

“…This discrepancy can be attributed to soaking the lentils, which leads to a decrease in NHI but was not performed here, and to the different cooking conditions. The plant-source mixture had a slightly higher iron content than the lentil mixture alone, because the lupin flour provides additional iron, as it has an iron content of 2.5–11.4 mg/100 g according to Eberl et al [ 30 ].…”

WisDM Green: Harnessing Artificial Intelligence to Design and Prioritize Compound Combinations in Peat Moss for Sustainable Farming Applications

“…Furthermore, a systemic review of databases from Australia indicated a 30%‐50% decline in the iron content of vegetables. [ 64 ] A separate study assessed archived wheat grain samples collected from 1950 to 2016 and discovered an imbalance in carbohydrate/protein content after the 1960s. [ 65 ] Notably, uptrend increases in CO 2 and temperature were observed in the same time period, suggesting climate change may have impacted both yield and the nutritional content.…”